Copy stable/10@r272459 to releng/10.1 as part of
the 10.1-RELEASE process.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Fix a group of typos:
preceed -> precede,
preceeded -> preceded,
preceeding -> preceding.

Submitted by: Andre Guibert de Bruet <andy@siliconlandmark.com>

Start each of the license/copyright comments with /*-, minor shuffle of lines

Extend critical section protection around portions of selection processing
that cannot tolerate changes to the waiting for selection queue by the
host or the host canceling an active selection.

ahc_eisa.c:
ahc_pci.c:
ahd_pci.c:
aic7xxx.c:
aic79xx.c:
aic_osm_lib.c:
aic_osm_lib.h:
Use common OSM routines from aic_osm_lib for bus dma operations,
delay routines, accessing CCBs, byte swapping, etc.

aic7xxx_pci.c:
Provide a better description for the 2915/30LP on attach.

aic7xxx.c:
aic79xx.c:
aic7770.c:
aic79xx_pci.c:
aic7xxx_pci.c:
aic7xxx_93cx6.c:
Move FBSDID behind an ifdef so that these core files will
still compile under other OSes.

aic79xx.h:
aic79xx_pci.c:
aic79xx.seq:
To speed up non-packetized CDB delivery in Rev B, all CDB
acks are "released" to the output sync as soon as the
command phase starts. There is only one problem with this
approach. If the target changes phase before all data are
sent, we have left over acks that can go out on the bus in
a data phase. Due to other chip contraints, this only
happens if the target goes to data-in, but if the acks go
out before we can test SDONE, we'll think that the transfer
has completed successfully. Work around this by taking
advantage of the 400ns or 800ns dead time between command
phase and the REQ of the new phase. If the transfer has
completed successfully, SCSIEN should fall *long* before we
see a phase change. We thus treat any phasemiss that
occurs before SCSIEN falls as an incomplete transfer.

aic79xx.h:
Add the AHD_FAST_CDB_DELIVERY feature.

aic79xx_pci.c:
Set AHD_FAST_CDB_DELIVERY for all Rev. B parts.

aic79xx.seq:
Test for PHASEMIS in the command phase for
all AHD_FAST_CDB_DELIVERY controlelrs.

ahd_pci.c:
ahc_pci.c:
aic7xxx.h:
aic79xx.h:
Move definition of controller BAR offsets to core header files.

aic7xxx.c:
aic79xx.c:
In the softc free routine, leave removal of a softc from the
global list of softcs to the OSM (the caller of this routine).
This allows us to avoid holding the softc list_lock during device
destruction where we may have to sleep waiting for our recovery
thread to halt.

ahc_pci.c:
Use ahc_pci_test_register access to validate I/O mapped in
addition to the tests already performed for memory mapped
access.

Remove unused ahc_power_state_change() function. The PCI
layer in both 4.X and 5.X now offer this functionality.

ahd_pci.c:
Remove reduntant definition of controller BAR offsets. These
are also defined in aic79xx.h.

Remove unused ahd_power_state_change() function. The PCI
layer in both 4.X and 5.X now offer this functionality.

aic7xxx.c:
aic79xx.c:
aic79xx.h:
aic7xxx.h:
aic7xxx_osm.c:
aic79xx_osm.c:
Move timeout handling to the driver cores. In the case
of the aic79xx driver, the algorithm has been enhanced
to try target resets before performing a bus reset. For
the aic7xxx driver, the algorithm is unchanged. Although
the drivers do not currently sleep during recovery (recovery
is timeout driven), the cores do expect all processing to
be performed via a recovery thread. Our timeout handlers
are now little stubs that wakeup the recovery thread.

aic79xx.c:
aic79xx.h:
aic79xx_inline.h:
Change shared_data allocation to use a map_node so
that the sentinel hscb can use this map node in
ahd_swap_with_next_hscb. This routine now swaps
the hscb_map pointer in additon to the hscb
contents so that any sync operations occur on
the correct map.

physaddr -> busaddr

Pointed out by: Jason Thorpe <thorpej@wasabisystems.com>

aic79xx.c:
Make more use of the in/out/w/l/q macros for accessing
byte registers in the chip.

Correct some issues in the ahd_flush_qoutfifo() routine.
o Run the qoutfifo only once the command channel
DMA engine has been halted. This closes a window
where we might have missed some entries.
o Change ahd_run_data_fifo() to not loop to completion.
If we happen to start on the wrong FIFO and the other
FIFO has a snapshot savepointers, we might deadlock.
This required our delay between FIFO tests to be
moved to the ahd_flush_qoutfifo() routine.
o Update/add comments.
o Remove spurious test for COMPLETE_DMA list being empty
when completing transactions from the GSFIFO with
residuals. The SCB must be put on the COMPLETE_DMA
scb list unconditionally.
o When halting command channel DMA activity, we must
disable the DMA channel in all cases but an update
of the QOUTFIFO. The latter case is required so
that the sequencer will update its position in the
QOUTFIFO. Previously, we left the channel enabled
for all "push" DMAs. This left us vulnerable to
the sequencer handling an SCB push long after that
SCB was already processed manually by this routine.
o Correct the polarity of tests involving
ahd_scb_active_in_fifo(). This routine returns
non-zero for true.

Return to processing bad status completions through
the qoutfifo. This reduces the time that the sequencer
is kept paused when handling transactions with bad
status or underruns.

When waiting for the controller to quiece selections,
add a delay to our loop. Otherwise we may fail to wait
long enough for the sequencer to comply.

On H2A4 hardware, use the slow slewrate for non-paced
transfers. This mirrors what the Adaptec Windows
drivers do.

On the Rev B. only slow down the CRC timing for
older U160 devices that might need the slower timing.
We define "older" as devices that do not support
packetized protocol.

Wait up to 5000 * 5us for the SEEPROM to become unbusy.
Write ops seem to take much longer than read ops.

aic79xx.seq:
For controllers with the FAINT_LED bug, turn the diagnostic
led feature on during selection and reselection. This covers
the non-packetized case. The LED will be disabled for
non-packetized transfers once we return to the top level idle
loop. Add more comments about the busy LED workaround.

Extend a critical section around the entire
command channel idle loop process. Previously
the portion of this handler that directly manipulated
the linked list of completed SCBs was not protected.
This is the likely cause of the recent reports of
commands being completed twice by the driver.

Extend critical sections across the test for,
and the longjump to, longjump routines. This
prevents the firmware from trying to jump to
a longjmp handler that was just cleared by the
host.

Improve the locations of several critical section
begin and end points. Typically these changes
remove instructions that did not need to be
inside a critical section.

Close the "busfree after selection, but before busfree
interrupts can be enabled" race to just a single sequencer
instruction. We now test the BSY line explicitly before
clearing the busfree status and enabling the busfree
interrupt.

Close a race condition in the processing of HS_MAILBOX
updates. We now clear the "updated" status before the
copy. This ensures that we don't accidentally clear
the status incorrectly when the host sneaks in an update
just after our last copy, but before we clear the status.
This race has never been observed.

Don't re-enable SCSIEN if we lose the race to disable SCSIEN
in our interrupt handler's workaround for the RevA data-valid
too early issue.

aic79xx_inline.h:
Add comments indicating that the order in which bytes are
read or written in ahd_inw and ahd_outw is important. This
allows us to use these inlines when accessing registers with
side-effects.

aic79xx_pci.c:
The 29320 and the 29320B are 7902 not 7901 based products.
Correct the driver banner.

aic7xxx.h:
Enable the use of the auto-access pause feature
on the aic7870 and aic7880. It was disabled due
to an oversight.

aic7xxx.reg:
Move TARG_IMMEDIATE_SCB to alias LAST_MSG to
avoid leaving garbage in MWI_RESIDUAL. This
prevents spurious overflows whn operating target
mode on controllers that require the MWI_RESIDUAL
work-around.

aic7xxx.seq:
AHC_TMODE_WIDEODD_BUG is a bug, not a softc flag.
Reference the correct softc field when testing
for its presence.

Set the NOT_IDENTIFIED and NO_CDB_SENT bits
in SEQ_FLAGS to indicate that the nexus is
invalid in await busfree.

aic7xxx_93cx6.c:
Add support for the C56/C66 versions of the EWEN and EWDS
commands.

aic7xxx.c:
aic7xxx_pci.c:
Move test for the validity of left over BIOS data
to ahc_test_register_access(). This guarantees that
any left over CHIPRST value is not clobbered by our
register access test and lost to the test that was
in ahc_reset.

FIFOEMP can lag LAST_SEG_DONE in the Ultra2 and U160
hardware. Wait a few extra clocks for FIFOEMP to assert
before calling an overrun.

Approved by: RE

Correct/Simplify ignore wide residue message handling

aic7xxx.c:
In ahc_handle_ign_wide_residue():
o Use SCB_XFERLEN_ODD SCB field to determine transfer
"oddness" rather than the DATA_COUNT_ODD logic.
SCB_XFERLEN_ODD is toggled on every ignore wide
residue message so that multiple ignore wide residue
messages for the same transaction are properly supported.
o If the sg list has been exausted, the sequencer
doesn't bother to update the residual data count
since it is known to be zero. Perform the zeroing
manually before calculating the remaining data count.
o Ensure that SG_LIST_NULL is cleared in the
residual sg pointer for "mid-transfer" ignore
wide residue cases.
o Use multibyte in/out macros instead of shifting/masking
by hand.

aic7xxx.h:
Modify the SCB_GET_LUN() macro to mask the lun hardware
SCB field with LID. This leaves two bits in the LUN
field that can be used for other purposes.

aic7xxx.reg:
Change LID to be 0x3F. This is the maximum supported
lun size for non-packetized SCSI. Map the top bit
of the lun to SCB_XFERLEN_ODD. The host must set
this bit whenever a transfer is an odd length.

Remove the ODD_SEG bit field that was used to carry the odd
transfer length information through the SG cache. This
is obviated by SCB_XFERLEN_ODD field.

Remove the DATA_COUNT_ODD scratch ram byte that was used
dynamicaly compute data transfer oddness. This is obviated
by SCB_XFERLEN_ODD field.

aic7xxx.seq:
Be more careful in our handling of the SCB_LUN field. It
must be masked with LID if only lun information is desired.

Remove all updates to the DATA_COUNT_ODD scratch ram field.
Remove all uses of ODD_SEG. These two save quite a few
sequencer instructions.

Use SCB_XFERLEN_ODD to validate the end of transfer
ignore wide residue message case.

aic7xxx_inline.h:
In ahc_queue_scb(), setup the SCB_XFERLEN_ODD field.

Approved by: RE

aic7xxx.reg:
Add a constant for the controller's stack size and the
maximum scsi offset.

aic7xxx.seq:
Style nit. The source is implied to be the destination
unless overridden in an "and" instruction.

Update target mode code for changes in identify seen
sequencer flags.

aic7xxx_pci.c:
Ensure that the PCIERRGENDIS bit is set in the
PCIERRGEN config space register. Perhaps this
is a reason for the spurios parity errors reported
on U160 controllers.

Honor the AHC_NO_BIOS_INIT flag.

Allow PCI interrupt reporting to be disabled,
by clearing the PERRRESEN bit in the command
register. This option is now enabled via a new
softc flag: AHC_DISABLE_PCI_PERR.

Disable SERR and pause the controller prior to performing
our mmapped I/O test. This should handle the case of
controllers that do not "auto-access pause". For legacy
controllers, use SCB ram instead of scratch ram since
the latter may contain settings left over from the BIOS
that we will use if an seeprom is not found.

Make use of new ahc_inl/outl() inlines.

aic7xxx.h:
Reformat a few comments to follow driver style.

Add a controller flags that indicate that a controller
has not been initialized by the BIOS and whether to
disable PCI parity errors..

Remove stack probing softc members.

Add a few more syncrate constants that are useful in speed
fallback calculations.

Add the SHOW_MASKED_ERRORS debug flag.

aic7xxx.h:
aic7xxx.c:
Implement the SCB_SILENT flag. This is useful for
hushing up the driver during DV or other operations
that we expect to cause transmission errors. The
messages will still print if the SHOW_MASKED_ERRORS
debug option is enabled.

aic7xxx_inline.h:
Implement ahc_[in|out][w|l|q]. This removes the need
for manual 'or and shift" type operations throughout
the driver.

aic7xxx.c:
Move SELTO dignostic so that the SCB is still valid
when we use it for printing path information.

If we are narrow, limit syncrate to Ultra2.

Don't clobber ppr_options when forcing a renegotiation.
The current ppr_options may be referenced while queuing
new commands. Don't set our width to unknown when forcing
negotiation on narrow controllers. This will confuse the
negotiation code into negotiating with a wide message on
narrow controllers.

Add an "asserting atn" diagnostic with controller/target
information.

Remove the probe_stack code. The stack is always
4 deep on legacy controllers, so probing is pointless.
This also avoids an issue where probing the stack would
upset the aic7770.

In ahc_reset(), record whether or not we found the
controller in a reset state. If the controller was
already reset, assume that no BIOS has initialized
the controller and ignore left over scratch ram
settings.

Fix an ifdef bug that caused sequencer debugging to
be enabled always.

Clear the ultraenb flag in our tstate during startup.
The ultraenbled'ness of a device is recorded in the user
transfer settings. tstate->ultraenb bitmask indicates
which devices we have negotiated an ultra speed with.
Just after initialization, we are async. Setting the
ultraenb flag while async seems to be harmless, but it
was confusing to see the ULTRAENB flag set in the SCB.

Enhance residual diagnostic to indicate if the residual
if for sense information or normal data transfers.

Indicate the features, bugs, and flags set in the softc
that are used to control firmware patch download when
booting verbose.

In ahc_dump_card_state() fix a logic reversal. The
SCSIPHASE register only exists on U160 controllers.
The SCSISIGI register exists on all controllers. Not
the other way around. Also print out the ERROR register.

Allow ahc_dump_card_state() to be called when the sequencer
is not paused. Add dump card state markers as in the U320
driver.

Bring in many bugfixes and changes obtained from formal testing:

aic7xxx.c:
aic7xxx.h:
aic7xxx.reg:
aic7xxx.seq:
Bring in the protocol violation handler from the U320
driver and replace the NO_IDENT sequencer interrupt code
with the PROTO_VIOLATION code. Support for this code
required the following changes:

SEQ_FLAGS:
IDENTIFY_SEEN -> NOT_IDENTIFIED
Added NO_CDB_SENT

SCB_CONTROL:
TARGET_SCB == STATUS_RCVD for initiator mode

scb->flags:
Added SCB_TARGET_SCB since we cannot rely on
TARGET_SCB as a target/initiator differentiator
due to it being overloaded in initiator mode to
indicate that status has been received.

aic7xxx.seq:
Move data fifo CLRCHN to mesgin_rdptrs which is a safer
location for doing this operation. This also saves a
sequencer instruction.

aic7xxx.c:
aic7xxx.h:
Change ahc/ahd_upate_neg_request() to take a "negotiation
type" enum that allows us to negotiate:
o only if the goal and current parameters differ.
o only if the goal is non-async
o always - even if the negotiation will be for async.
aic7xxx.seq:
Reset the FIFO whenever a short CDB transfer occurs
so that the FIFO contents do not corrupt a future CDB
transfer retry.

Add support for catching the various protocol violations
handled by ahc_handle_protocol_violation.

Reformat some comments.

aic7xxx.c:
aic7xxx.h:
Just for safety, have the aic7xxx driver probe
the stack depth.

aic7xxx.c:
aic7xxx.h:
Save and restore stack contents during diagnostics.
Some chip variants overwrite stale entries on a
stack "pop".

Don't use 0 to probe the stack depth. 0 is the typical
value used to backfill the stack if entries are overwritten
on a "pop".

aic7xxx.h:
Add a missing typedef.

Collapse SCB flag entries so they are bit contiguous.

Add AHD_ULTRA2_XFER_PERIOD for narrow fallback calculations

aic7xxx.c:
Don't panic (as a diagnostic to catch bugs) if we decided to
force the renegotiation of async even if we believe we are
already async. This should allow us to negotiate async instead
of the full user goal rate during startup if bus resets are
disabled.

Add a space to the end of the ahc/ahd_print_devinfo routines
so that it behaves as expected by the code that uses it.

Only force a renegotiation on a selection timeout
if the SCB was valid. Doing otherwise may be dangerous
as the connection was not valid for an unknown reason.

Add additional diagnostic output to ahc_dump_card_state(),
and have it use the register pretty printing functions.

Update ahc_reg_print() to handle a NULL cur_col.

Add a newline to ahc_dump_card_state() output.

Bring back "use_ppr". We need to use_ppr anytime
doppr is true or we have non-zero protocol options.
The later case was not handled in the recent removal
of use_ppr.

Move a comment and remove a useless clearing of use_ppr.

Don't disable ENBUSFREE when single stepping on
a DT capable controller. We cannot re-enable unexpected
busfree detection, so we must clear BUSFREE on each
step instead.

Correct the lookup of the SCB ID in ahc_handle_proto_error.

Remove a diagnostic printf.
Remove unecessary restoration of the STACK for older
chips.

Approved by: re (blanket)

Add a prefix to be used for assembler generated tables and
functions for register pretty-printing.

Only clear SELDO once we've recorded enough information for
the host to understand that the connection is valid. The
host uses the SELDO status as a handshake to close this
race window.

Correct a bug in target mode handling of non-disconnected
transactions. The host would indicate the correct SCB to
DMA by setting the SCB id in the currently selected hardware
SCB. Unfortunately, we would then immediated allocate a
hardware SCB which, depending on the access patern might not
be the same hardware SCB that the host setup for us. Avoid
this by having the host put the SCBID into scratch ram.

Major update to the aic7xxx driver:

ahc_eisa.c:
ahc_pci.c:
Conform to new aic7xxx IRQ API.

Adapt to aic7xxx_freebsd -> aic7xxx_osm changes.

aic7770.c:
Disable card generated interrupt early in our probe for
"extra safety"

Commonize some seeprom code with the PCI side of the driver.

aic7xxx.c:
Correctly initialize a few scratch ram locations during
a sequencer restart. This avoids spurious sequencer ram
parity errors in some configurations.

Include the softc in ahc_update_residual calls. We need it
for some diagnostics in this code path.

Flag a data overrun on an auto-request sense failure as a
CAM_AUTOSENSE_FAIL rather than a CAM_DATA_RUN_ERR.

Force a renegotiation after noticing a parity error. This
covers targets that lose our negotiation settings but don't
bother to give us a unit attention condition. This can happen
if a target fails during a reselection of us during a cable
pull.

Convert some code to using constants.

Fix some typos.

Correct target mode message loop handling. ahc_clear_msg_state
was not clearing the "need to go to message out phase" bit once
our loop was over.

Simplify some abort handling code.

Include tag information in target mode immediate notify events.

When shutting down EISA controllers, don't EISA BIOS settings in
the high portions of scratch ram. This fixes warm boot issues on
some systems.

Save a bit of space by only allocating the SCBs that we can use.

Avoid some code paths in ahc_abort_scbs() if we are currently
acting as a target.

Correctly cleanup stranded SCBs in the card's SCB array. These
are SCBs who's mapping has already been torn down by code that
aborted the SCB by seeing it in another list first.

Add a comment about some potential bus reset issues for target
mode on Twin (EISA only) controllers.

aic7xxx.h:
Cleanup the hardware scb definitions a bit.

Allocate a ful 256 byte scb mapping index. This simplifies
the lookup code since the table covers all possible (and potentially
bogus) values.

Make AHC_DEBUG work again.

aic7xxx.reg:
Updates to hardware SCB definition.

New definitions for target mode fixes.

aic7xxx.seq:
In target mode, initialize SAVED_LUN just after we receive
the identify message. It may be required in the error recovery
path when a normal cdb packet (includes lun) is not sent up to
the host for processing.

Respond to irregular messages during a selection in target mode.

Defer looking for space for a cdb packet until we are about to
enter command phase. We want to be able to handle irregular messages
even if we would otherwise return QUEUE_FULL or BUSY.

Add support for sending Ignore Wide Residue messages as a target.

In the disable disconnect case in target mode, set our transfer
rate correctly once data are availble.

aic7xxx_93cx6.c:
aic7xxx_93cx6.h:
Add the ability to write and erase the seeprom.

aic7xxx_inline.h:
Correct Big Endian handling of large cdb sizes (> 12 bytes).

Adaptec to changes in the calc_residual API.

Correct a target mode bug where we always attempted to service
the input queue even if no progress could be made due to lack
of ATIOs.

aic7xxx_osm.c:
Adaptec to new IRQ mapping API. The new API allows the core
to only enable our IRQ mapping once it is safe (sufficient
initialization) to do so.

Slap bootverbose protection around some diagnostics.

Only attempt DT phases if we are wide.

aic7xxx_osm.h:
Enable big endian support.

Adjust for IRQ API change.

aic7xxx_pci.c:
Be more careful about relying on subvendor 9005 information.
We now only trust it for HBAs. This should allow the driver
to attach to some MBs where the subvendor/device information
does not follow the Adaptec spec.

Only enable interrupts on the card once we are fully setup.

Disable external SCB ram usage on the aic7895. I have not
been able to make it 100% reliable.

Adjust to seeprom routines being properly prefixed with "ahc".

Fix a few bugs in the external SCB ram probing routine. We
need to clear any parity errors we've triggered during the
probe to avoid future, fatal, interrupts.

If we detect an invalid cable combination, pretent there are
no cable at all. This will enable all of the terminators
which is probably the safest configuration we can "guess".

MFC after: 4 days

aic7xxx.c:
Correct an off by one in our critical section handling.
SEQADDR always reads the next instruction to execute,
so we must subtract one from its value before making
comparisons with entries in the critical section table.

Print a few additional registers whenever we dump
card state.

Show the SCB_CONTROL and SCB_TAG values for all pending
SCBs in card SCB ram when dumping card state.

aic7xxx.seq:
Fix a bug introduced while optimizing the SDPTR path.
We would ack the SDPTR message twice on Ultra2 or better
chips if it occurred after all data had been transferred
for a transaction.

Change our workaround for the PCI2.1 retry bug on some
chips. Although the previous workaround was logically
correct, its faster method of draining the FIFO seemed
to occassionally confuse the FIFO state. We now drain
the FIFO at half the speed which avoids the problem.

aic7xxx_pci.c:
Chips with the PCI 2.1 retry bug can't handle a 16byte
cachesize. If the cachesize is set to 16bytes, drop
it to 0.

ahc_pci.c:
If bus_dma will give us addresses > 32 bits, setup our dma tag
to accept up to 39bit addresses.

aic7770.c:
Update the softc directly rather than use an intermediate
"probe_config" structure.

aic7xxx.c:
Complete core work to support 39bit addresses for bulk data
dma operations. Controller data structures still must reside
under the 4GB boundary to reduce code/data size in the sequencer
and related data structures. This has been tested under Linux
IA64 and will be tested on IA64 for FreeBSD as soon as our port
can run there.

Add bus dmamap synchronization calls around manipulation of
all controller/kernel shared host data structures.

Implement data pointer reinitialation for a second data phase
in a single connection in the kernel rather than bloat the
sequencer. This is an extremely rare operation (does it ever
happen?) and the sequencer implementation was flawed for some
of the newest chips.

Don't ever allow our target role to initiate a PPR. This
is forbidden by the SCSI spec.

Add a few missing endian conversions in the ignore wide pointers
code. The core has been tested on the PPC under Linux and should
work for FreeBSD PPC. As soon as I can test the OSM layer for
FreeBSD PPC, I will.

Move some of ahc_softc_init() into ahc_alloc() now that the
probe_config structure is gone.

Add a 4GB boundary condition on all of our dma tags. 32bit
DAC under PCI only works on a single 4GB "page". Although
we can cross 4GB on a true 64bit bus, the card won't always
be installed in one and we can save code space and cost in
implementing high address support by assuming the high DWORD
address will never change.

Add diagnostics to ahc_search_qinfifo().

Correct a target mode issue with bus resets. To avoid an
interrupt storm from a malicious third party holding the
reset line, the sequencer would defer re-enabling the reset
interrupt until either a select-out or select-in. Unfortunately,
the select-in enable bit is cleared by a bus reset, so a second
reset will render the card deaf to an initiator's attempts to
contact it. We now re-enable bus reset interrupts immediately
if the target role is enabled.

aic7xxx.h:
Remove struct ahc_probe_config.

SCB's now contain a pointer to the sg_map_node so we can perfrom
bus dma sync operations on the SG list prior to queuing a command.

aic7xxx.reg:
Register the Perforce ID for this file with the VERSION keyword
so it is printed in generated files.

Add the DSCOMMAND1 register which is used to access the high
DWORD of address bits.

Add the data pointer reinitialize sequencer interrupt code.

aic7xxx.seq:
Register the Perforce ID for this file with the VERSION keyword
so it is printed in generated files.

Remove code to re-enable the bus reset interrupt after a select-in.
In target mode we cannot defer this operation as ENSELI is cleared
by a bus reset.

Complete 39bit support.

Generate a sequencer inteerrupt rather than handle the data
pointers re-initialitation in the sequencer.

Inline the "seen identify" assertion to save a few cycles.

Short circuit the update of our residual data if we have
fully completed a transfer. The residual is correct from
our last S/G load operation.

Short circuit full SDPTR processing if the residual is 0.
Just mark the transfer as complete.

aic7xxx_93cx6.c:
Synchronize perforce IDs.

aic7xxx_freebsd.c:
Complete untested 39bit support.

Add missing endia conversions.

Clear our residuals prior to starting a command. The
update residual code in the core only sets the residual
if there is one.

aic7xxx_freebsd.h:
Modeify ahc_dmamap_sync() macros to take an offset and a length.
This is how sync operations are performed in NetBSD, and we should
update our bus dma implementation to match.

aic7xxx_inline.h:
Add data structure synchronization helper functions.

Fix a bug in ahc_intr() where we would not clear our unsolicited
interrupt counter after running our PCI interrupt handler. This
may have been the cause of the spurious PCI interrupt messages.

aic7xxx_pci.c:
Adjust for loss of probe_config structure.

Guard against bogus 9005 subdevice information as seen on some
IBM MB configurations.

Add 39bit address support.

MFC after: 10 days

ahc_eisa.c:
ahc_pci.c:
Prepare for making ahc a module by adding module dependency
and version info.

aic7770.c:
Remove linux header ifdefs. The headers are handled differently
in Linux where local includes (those using "'s instead of <>'s)
are allowed.

Don't map our interrupt until after we are fully setup to
handle interrupts. Our interrupt line may be shared so
an interrupt could occur at any time.

aic7xxx.c:
Remove linux header ifdefs.

current->curr to avoid Linux's use of current as a
#define for the current task on some architectures.

Add a helper function, ahc_assert_atn(), for use in
message phases we handle manually. This hides the fact
that U160 chips with the expected phase matching disabled
need to have SCSISIGO updated differently.

if (ahc_check_residual(scb) != 0)
ahc_calc_residual(scb);
else
ahc_set_residual(scb, 0);

becomes:

ahc_update_residual(scb);

Modify scsi parity error (or CRC error) handling to
reflect expected phase being disabled on U160 chips.

Move SELTO handling above BUSFREE handling so we can
use the new busfree interrupt behavior on U160 chips.

In ahc_build_transfer_msg() filter the period and ppr_options
prior to deciding whether a PPR message is required.
ppr_options may be forced to zero which will effect our
decision.

Correct a long standing but latent bug in ahc_find_syncrate().
We could choose a DT only rate even though DT transfers were
disabled. In the CAM environment this was unlikely as CAM
filters our rate to a non-DT value if the device does not
support such rates.

When displaing controller characteristics, include the
speed of the chip. This way we can modify the transfer
speed based on optional features that are enabled/disabled
in a particular application.

Add support for switching from fully blown tagged queing
to just using simple queue tags should the device reject
an ordered tag.

Remove per-target "current" disconnect and tag queuing
enable flags. These should be per-device and are not
referenced internally be the driver, so we let the OSM
track this state if it needs to.

Use SCSI-3 message terminology.

aic7xxx.h:
The real 7850 does not support Ultra modes, but there are
several cards that use the generic 7850 PCI ID even though
they are using an Ultra capable chip (7859/7860). We start
out with the AHC_ULTRA feature set and then check the
DEVSTATUS register to determine if the capability is really
present.

current -> curr

ahc_calc_residual() is no longer static allowing it to
be called from ahc_update_residual() in aic7xxx_inline.h.

Update some serial eeprom definitions for the latest
BIOS versions.

aic7xxx.reg:
Add a combined DATA_PHASE mask to the SCSIPHASE register
definition to simplify some sequencer code.

aic7xxx.seq:
Take advantage of some performance features available only
on the U160 chips. The auto-ack feature allows us to ack
data-in phases up to the data-fifo size while the sequencer
is still setting up the DMA engine. This greatly reduces
read transfer latency and simplifies testing for transfer
complete (check SCSIEN only). We also disable the expected
phase feature, and enable the new bus free interrupt behavior,
to avoid a few instructions.

Re-arrange the Ultra2+ data phase handling to allow us to
do more work in parallel with the data fifo flushing on a
read.

On an SDTR, ack the message immediately so the target can
prepare the next phase or message byte in parallel with
our work to honor the message.

aic7xxx_93cx6.c:
Remove linux header ifdefs.

aic7xxx_freebsd.c:
current -> curr

Add a module event handler.

Handle tag downgrades in our ahc_send_async() handler.
We won't be able to downgrade to "basic queuing" until
CAM is made aware of this queuing type.

aic7xxx_freebsd.h:
Include cleanups.

Define offsetof if required.

Correct a few comments.

Update prototype of ahc_send_async().

aic7xxx_inline.h:
Implement ahc_update_residual().

aic7xxx_pci.c:
Remove linux header ifdefs.

Correct a few product strings.

Enable several U160 performance enhancing features.

Modify Ultra capability determination so we will enable
Ultra speeds on devices with a 7850 PCI id that happen
to really be a 7859 or 7860.

Don't map our interrupt until after we are fully setup to
handle interrupts. Our interrupt line may be shared so
an interrupt could occur at any time.

aic7770.c:
aic7xxx_pci.c:
Enable board generation of interrupts only once our handler is
in place and all other setup has occurred.

aic7xxx.c:
More conversion of data types to ahc_* names. tmode_tstate and
tmode_lstate are the latest victims.

Clean up the check condition path by branching early rather
than indenting a giant block of code.

Add support for target mode initiated sync negotiation.
The code has been tested by forcing the feature on for
all devices, but for the moment is left inaccesible until
a decent mechanism for controlling the behavior is complete.
Implementing this feature required the removal of the
old "target message request" mechanism. The old method
required setting one of the 16 bit fields to initiate
negotiation with a particular target. This had the nice
effect of being easy to change the request and have it
effect the next command. We now set the MK_MESSAGE bit
on any new command when negotiation is required. When
the negotiation is successful, we walk through and clean
up the bit on any pending commands. Since we have to walk
the commands to reset the SCSI syncrate values so no additional
work is required. The only drawback of this approach is that
the negotiation is deferred until the next command is queued to
the controller. On the plus side, we regain two bytes of
sequencer scratch ram and 6 sequencer instructions.

When cleaning up a target mode instance, never remove the
"master" target mode state object. The master contains
all of the saved SEEPROM settings that control things like
transfer negotiations. This data will be cloned as the
defaults if a target mode instance is re-instantiated.

Correct a bug in ahc_set_width(). We neglected to update
the pending scbs to reflect the new parameters. Since
wide negotiation is almost always followed by sync
negotiation it is doubtful that this had any real
effect.

When in the target role, don't complain about
"Target Initiated" negotiation requests when an initiator
negotiates with us.

Defer enabling board interrupts until after ahc_intr_enable()
is called.

Pull all info that used to be in ahc_timeout for the FreeBSD
OSM into ahc_dump_card_state(). This info should be printed
out on all platforms.

aic7xxx.h:
Add the SCB_AUTO_NEGOITATE scb flag. This allows us to
discern the reason the MK_MESSAGE flag is set in the hscb
control byte. We only want to clear MK_MESSAGE in
ahc_update_pending_scbs() if the MK_MESSAGE was set due
to an auto transfer negotiation.

Add the auto_negotiate bitfield for each tstate so that
behavior can be controlled for each of our enabled SCSI
IDs.

Use a bus interrupt handler vector in our softc rather
than hard coding the PCI interrupt handler. This makes
it easier to build the different bus attachments to
the aic7xxx driver as modules.

aic7xxx.reg:
Remove the TARGET_MSG_REQUEST definition for sequencer ram.

aic7xxx.seq:
Fix a few target mode bugs:

o If MK_MESSAGE is set in an SCB, transition to
message in phase and notify the kernel so that
message delivery can occur. This is currently
only used for target mode initiated transfer
negotiation.

o Allow a continue target I/O to compile without
executing a status phase or disconnecting. If
we have not been granted the disconnect privledge
but this transfer is larger than MAXPHYS, it may
take several CTIOs to get the job done.

Remove the tests of the TARGET_MSG_REQUEST field in scratch ram.

aic7xxx_freebsd.c:
Add support for CTIOs that don't disconnect. We now defer
the clearing of our pending target state until we see a
CTIO for that device that has completed sucessfully.

Be sure to return early if we are in a target only role
and see an initiator only CCB type in our action routine.

If a CTIO has the CAM_DIS_DISCONNECT flag set, propogate
this flag to the SCB. This flag has no effect if we've
been asked to deliver status as well. We will complete
the command and release the bus in that case.

Handle the new auto_negotiate field in the tstate correctly.

Make sure that SCBs for "immediate" (i.e. to continue a non
disconnected transaction) CTIO requests get a proper mapping
in the SCB lookup table. Without this, we'll complain when
the transaction completes.

Update ahc_timeout() to reflect the changes to ahc_dump_card_state().

aic7xxx_inline.h:
Use ahc->bus_intr rather than ahc_pci_intr.

This is an MFC candidate.

In our idle loop, use an or instruction to set PRELOADEN rather
than rewriting the contents of DMAPARAMS to DFCNTRL. The later
may re-enable the DMA engine if the idle loop is called to complete
the preload of at least one segment when a target disconnects on
an S/G segment boundary but before we have completed fetching the
next segment. This correts a hang, usually in message out phase,
when this situation occurs. This bug has been here for a long
time, so the situation is rare, but not impossible to reproduce.
It only affected Ultra2/U160 controllers.

Correct a few comments.

Extra Sanity. Make sure that SCSIEN is also turned off, along with
HDMAEN, at the end of the data phase.

This is an MFC candidate.

aic7xxx.c:
Correct code that traverses the phase table. A much too quick
push to staticize this structure resulted in non-functional
lookup code. This corrects the printing of the phase where
a timeout occurred.

aic7xxx.reg:
Use FIFOQWDEMP as the name for bit 5 of DFSTATUS just like
the Adaptec data books.

aic7xxx.seq:
Refine the 2.1 PCI retry bug workaround for certain, non-ULTRA2,
controllers. When the DMA of an SCB completes, it can take
some time for HDONE to come true after MREQPEN (PCI memory request
pending) falls. If HDONE never comes true, we are in the hung
state and must manually drain the FIFO. We used to test HDONE for
3 clock cycles to detect this condition. This works on all of the
hardware I can personally test. Some controllers were reported
to take 4 clock cycles, so the last version of this code waited
4 clock cycles. This still didn't work for everyone. To fix this,
I've adjusted the work around so that even if the hardware hasn't
hung, but we run the work-around code, the result is a long winded
way to complete the transfer, rather than a hang.

This is an MFC candidate.

ahc_eisa.c:
Change aic7770_map_int to take an additional irq parameter.
Although we can get the irq from the eisa dev under FreeBSD,
we can't do this under linux, so the OSM interface must supply
this.

ahc_pci.c:
Move ahc_power_state_change() to the OSM. This allows us to
use a platform supplied function that does the same thing.
-current will move to the FreeBSD native API in the near
future.

aic7770.c:
Sync up with core changes to support Linux EISA.

We now store a 2 bit primary channel number rather
than a bit flag that only allows b to be the primary
channel. Adjust for this change.

aic7xxx.c:
Namespace and staticization cleanup. All exported symbols
use an "ahc_" prefix to avoid collisions with other modules.

Correct a logic bug that prevented us from dropping
ATN during some exceptional conditions during message
processing.

Take advantage of a new flag managed by the sequencer
that indicates if an SCB fetch is in progress. If so,
the currently selected SCB needs to be returned to the
free list to prevent an SCB leak. This leak is a rarity
and would only occur if a bus reset or timeout resulting
in a bus reset occurred in the middle of an SCB fetch.

Don't attempt to perform ULTRA transfers on ultra capable
adapters missing the external precision resistor required
for ultra speeds. I've never encountered an adapter
configured this way, but better safe than sorry.

Handle the case of 5MHz user sync rate set as "0" instead of 0x1c
in scratch ram.

If we lookup a period of 0 in our table (async), clear the scsi offset.

aic7xxx.h:
Adjust for the primary channel being represented as
a 2 bit integer in the flags member of the ahc softc.

Cleanup the flags definitions so that comment blocks are
not cramped.

Update seeprom definitions to correctly reflect the fact
that the primary channel is represented as a 2 bit integer.

Add AHC_ULTRA_DIASABLED softc flag to denote controllers
missing the external precision resistor.

aic7xxx.reg:
Add DFCACHETH to the definition of DFSTATUS for completness sake.

Add SEQ_FLAGS2 which currently only contains the SCB_DMA
(SCB DMA in progress) flag.

aic7xxx.seq:
Correct a problem when one lun has a disconnected untagged
transaction and another lun has disconnected tagged transactions.
Just because an entry is found in the untagged table doesn't
mean that it will match. If the match on the lun fails, cleanup
the SCB (return it to the disconnected list or free it), and snoop
for a tag message. Before this change, we reported an unsolicited
reselection. This bug was introduced about a month ago during an
overly aggressive optimization pass on the reselection code.

When cleaning up an SCB, we can't just blindly free the SCB. In
the paging case, if the SCB came off of the disconnected list, its
state may never have been updated in host memory. So, check the
disconnected bit in SCB_CONTROL and return the SCB to the disconnected
list if appropriate.

Manage the SCB_DMA flag of SEQ_FLAGS2.

More carefully shutdown the S/G dma engine in all cases by using
a subroutine. Supposedly not doing this can cause an arbiter hang
on some ULTRA2 chips.

Formatting cleanup.

On some chips, at least the aic7856, the transition from
MREQPEND to HDONE can take a full 4 clock cycles. Test
HDONE one more time to avoid this race. We only want our
FIFO hung recovery code to execute when the engine is
really hung.

aic7xxx_93cx6.c:
Sync perforce ids.

aic7xxx_freebsd.c:
Adjust for the primary channel being a 2 bit integer
rather than a flag for 'B' channel being the primary.

Namespace cleanup.

Unpause the sequencer in one error recovery path that
neglected to do so. This could have caused us to perform
a bus reset when a recovery message might have otherwise been
successful.

aic7xxx_freebsd.h:
Use AHC_PCI_CONFIG for controlling compilation of PCI
support consistently throughout the driver.

Move ahc_power_state_change() to OSM.

aic7xxx_inline.h
Namespace cleanup.

Adjust our interrupt handler so it will work in the edge
interrupt case. We must process all interrupt sources
when the interrupt fires or risk not ever getting an
interrupt again. This involves marking the fact
that we are relying on an edge interrupt in ahc->flags
and checking for this condition in addition to the
AHC_ALL_INTERRUPTS flag. This fixes hangs on the
284X and any other aic7770 installation where level
interrupts are not available.

aic7xxx_pci.c:
Move the powerstate manipulation code into the OSM. Several
OSes now provide this functionality natively.

Take another shot at using the data stored in scratch ram
if the SCB2 signature is correct and no SEEPROM data is
available. In the past this failed if external SCB ram
was configured because the memory port was locked. We
now release the memory port prior to testing the values
in SCB2 and re-acquire it prior to doing termination control.

Adjust for new 2 bit primary channel setting.

Trust the STPWLEVEL setting on v 3.X BIOSes too.

Configure any 785X ID in the same fashion and assume
that any device with a rev id of 1 or higher has the
PCI 2.1 retry bug.

aic7xxx.c:
Use the target offset rather than the target Id to reference
the untagged SCB array. The offset and id are identical save
in the twin channel case. This should correct several issues
with the 2742T.

Set the user and goal settings prior to setting the current
settings. This allows the async update routine to filter out
intermediate transfer negotiation updates that may be less
than interesting. The Linux OSM uses this to reduce the amount
of stuff printed to the console.

aic7xxx.seq:
Correct an issue with the aic7770 in twin channel mode.
We could continually attempt to start a selection even
though a selection was already occurring on one channel.
This might have the side effect of hanging our selection
or causing us to select the wrong device.

While here, create a separate polling loop for when we
have already started a selection. This should reduce
the latency of our response to a (re)selection. The diffs
look larger than they really are due to some code rearrangement
to optimize out a jmp.

aic7xxx_freebsd.c:
Use the target offset rather than the target Id to reference
the untagged SCB array. The offset and id are identical save
in the twin channel case. This should correct several issues
with the 2742T.

aic7xxx_inline.h:
Get back in sync with perforce revision ID.

aic7xxx_pci.c:
Identify adapters in ARO mode as such.

Ensure that not only the subvendor ID is correct (9005)
but also that the controller type field is valid before
looking at other information in the subdevice id. Intel
seems to have decided that their subdevice id of 8086
is more appropriate for some of their MBs with aic7xxx
parts than Adaptec's sanctioned scheme.

Add an exclusion entry for SISL (AAC on MB based adapters).
Adapters in SISL mode are owned by the RAID controller, so
even if a driver for the RAID controller is not present,
it isn't safe for us to touch them.

Preceed/preceeding are not english words. Use precede or preceding.

aic7xxx.c:
Style nits.

Make sure that our selection hardware is disabled
as soon as possible after detecting a busfree and
even go so far as to disable the selection hardware
in advance of an event that will cause a busfree
(ABORT or BUS DEVICE RESET message). The concern
is that the selection hardware will select a target
for which, after processing the bus free, there
will be no commands pending. The sequencer idle
loop will re-enable the selection should it still be
necessary.

In ahc_handle_scsiint(), clear SSTAT0 events several
PCI transactions (most notably reads) prior to clearing
SCSIINT. The newer chips seem to take a bit of time to
see the change which can make the clearing of SCSIINT
ineffective.

Don't bother panicing at the end of ahc_handle_scsiint().
Getting to the final else just means we lost the race
with clearing SCSIINT.

In ahc_free(), handle init-level 0. This can happen when we
fail the attach for RAID devices. While I'm here, also kill
the parent dma tag.

In ahc_match_scb(), consider initiator ccbs to be any
that are not from the target mode group. This fixes
a bug where an external target reset CCB was not getting
cleaned up by the reset code.

Don't bother freezing a ccb in any of our "abort" routines
when the status is set to CAM_REQ_CMP. This can happen
for a target reset ccb.

aic7xxx.reg:
Reserve space for a completion queue. This will be used
to enhance performance in the near future.

aic7xxx.seq:
Remove an optimization for the 7890 autoflush bug that
turned out to allow, in rare cases, some data to get
lost.

Implement a simpler, faster, fix for the PCI_2_1 retry
bug that hangs the sequencer on an SCB dma for certain chips.

Test against SAVED_SCSIID rather than SELID during target
reselections. This is how we always did it in the past,
but the code was modified while trying to work around an
issue with the 7895. SAVED_SCSIID takes into account
twin channel adapters such as the 2742T, whereas SELID
does not have the channel bit. This caused invalid
selection warnings and other strangeness on these cards.

aic7xxx_pci.c
Use the correct mask for checking the generic aic7892
entry.

Update Copyright notices for new year. (should have been in last commit).

ahc_eisa.c:
Initialize rid to 0. This doesn't seem to make any difference
(the driver doesn't care what rid it gets and no-one seems to
check rid's value), but follows standard conventions.

Pass in our device_t to ahc_alloc(). We now use device_T
softc storage, so passing NULL results in a panic.

Set the unit number in our softc so that the driver core
can retrieve it.

ahc_pci.c:
Set the unit number in our softc so that the driver core
can retrieve it.

aic7770.c:
Insert our softc into the list of softcs when initialization
is successful.

aic7xxx.c:
Remove a workaround for an aic7895 bug we will never trigger.

Add additional diagnostic info to ahc_dump_card_state().

Always panic the system if a sequencer assertion fails.

AHC_SCB_BTT is a "flag" not a "feature". Check the right
field in the softc.

Replace a hard coded number with a constant.

Guard against looping forever in ahc_pause_and_flushwork().
A hot eject or card failure may make the intstat register
return 0xFF, so limit the number of interrupts we'll process.

Correct the code in ahc_search_qinfifo() that guarantees that
the sequencer will see an abort collision if the qinfifo is
modified when a DMA is in progress. We now do this fixup
after modifying the queue. This guarantees that the HSCB
we place at the head of the queue is not the same as the
old head. Using "next hscb" (guaranteed not to be the
same as the first SCB) before clearing the queue could free
up the original head hscb to be used during a remove operation
placing it again at the head of the qinfifo.

aic7xxx.h:
Reduce the maximum number of outstanding commands to 253 from
254. To handle our output queue correctly on machines that only
support 32bit stores, we must clear the array 4 bytes at a
time. To avoid colliding with a DMA write from the sequencer,
we must be sure that 4 slots are empty when we write to clear
the queue. This reduces us to 253 SCBs: 1 that just completed
and the known three additional empty slots in the queue that
preceed it. Yahoo was able to force this race on one of their
systems. Interrupts were disabled for such a time that the
entire output queue was filled (254 entries complete without
any processing), and our 32bit write to clear the status clobbered
one entry.

Add a feature tag for devices that are removable.

aic7xxx.reg:
Never use the sequencer interrupt value of 0xF0. We need
to guanrantee that an INTSTAT value of 0xFF can only occur
during card failure or a hot-eject.

Align the busy targets table with the begining of scratch
space. This seems to appease a chip bug in the aic7895.

aic7xxx.seq:
Be sure to disable select-out after a bus free event that occurs
early in a selection. If we don't disable select-out, we will
believe that it is enabled even though a new selection will never
occur.

Move the clearing of SELDI to just before a jump. This appeases
another chip bug of the aic7895.

Make the target mode command loop a bit more efficient.

AHC_SCB_BTT is a "flag" not a "feature". Check the right
field in the softc.

Properly cleanup the last SCB we tested against should we
fail to properly find an SCB for a reselection.

Add some additional sequencer debugging code.

aic7xxx_freebsd.c:
Limit the driver to 253 outstanding commands per adapter.

Guard against overflow in timeout handling.

aic7xxx_inline.h:
AHC_SCB_BTT is a "flag" not a "feature". Check the right
field in the softc.

aic7xxx_pci.c:
Set the removable feature for the apa1480 cardbus and the 29160C
Compact PCI card.

Don't report high byte termination information for narrow cards.

Use a PCI read rather than a questionable delay when fetching/setting
termination settings.

ahc_eisa.c:
ahc_pci.c:
Add detach support.

Make use of soft allocated on our behalf by newbus.

For PCI devices, disable the mapping type we aren't
using for extra protection from rogue code.

aic7xxx_93cx6.c:
aic7xxx_93cx6.h:
Sync perforce IDs.

aic7xxx_freebsd.c:
Capture the eventhandle returned by EVENTHANDER_REGISTER
so we can kill the handler off during detach.

Use AHC_* constants instead of hard coded numbers in a
few more places.

Test PPR option state when deciding to "really" negotiate
when the CAM_NEGOTIATE flag is passed in a CCB.

Make use of core "ahc_pause_and_flushwork" routine in our
timeout handler rather than re-inventing this code.

Cleanup all of our resources (really!) in ahc_platform_free().
We should be all set to become a module now.

Implement the core ahc_detach() routine shared by all of
the FreeBSD front-ends.

aic7xxx_freebsd.h:
Softc storage for our event handler.

Null implementation for the ahc_platform_flushwork() OSM
callback. FreeBSD doesn't need this as XPT callbacks are
safe from all contexts and are done directly in ahc_done().

aic7xxx_inline.h:
Implement new lazy interrupt scheme. To avoid an extra
PCI bus read, we first check our completion queues to
see if any work has completed. If work is available, we
assume that this is the source of the interrupt and skip
reading INTSTAT. Any remaining interrupt status will be
cleared by a second call to the interrupt handler should
the interrupt line still be asserted. This drops the
interrupt handler down to a single PCI bus read in the
common case of I/O completion. This is the same overhead
as in the not so distant past, but the extra sanity of
perforning a PCI read after clearing the command complete
interrupt and before running the completion queue to avoid
missing command complete interrupts added a cycle.

aic7xxx.c:
During initialization, be sure to initialize all scratch
ram locations before they are read to avoid parity errors.
In this case, we use a new function, ahc_unbusy_tcl() to
initialize the scratch ram busy target table.

Replace instances of ahc_index_busy_tcl() used to unbusy
a tcl without looking at the old value with ahc_unbusy_tcl().

Modify ahc_sent_msg so that it can find single byte messages.
ahc_sent_msg is now used to determine if a transfer negotiation
attempt resulted in a bus free.

Be more careful in filtering out only the SCSI interrupts
of interest in ahc_handle_scsiint.

Rearrange interrupt clearing code to ensure that at least
one PCI transaction occurrs after hitting CLRSINT1 and
writting to CLRINT. CLRSINT1 writes take a bit to
take effect, and the re-arrangement provides sufficient
delay to ensure the write to CLRINT is effective. The
old code might report a spurious interrupt on some "fast"
chipsets.

export ahc-update_target_msg_request for use by OSM code.

If a target does not respond to our ATN request, clear
it once we move to a non-message phase. This avoids
sending a MSG_NOOP in some later message out phase.

Use max lun and max target constants instead of
hard-coded values.

Use softc storage built into our device_t under FreeBSD.

Fix a bug in ahc_free() that caused us to delete
resources that were not allocated.

Clean up any tstate/lstate info in ahc_free().

Clear the powerdown state in ahc_reset() so that
registers can be accessed.

Add a preliminary function for pausing the chip and
processing any posted work.

Add a preliminary suspend and resume functions.

aic7xxx.h:
Limit the number of supported luns to 64. We don't
support information unit transfers, so this is the
maximum that makes sense for these chips.

Add a new flag AHC_ALL_INTERRUPTS that forces the
processing of all interrupt state in a single invokation
of ahc_intr(). When the flag is not set, we use the
lazy interrupt handling scheme.

Add data structures to store controller state while
we are suspended.

Use constants instead of hard coded values where appropriate.

Correct some harmless "unsigned/signed" conflicts.

aic7xxx.seq:
Only perform the SCSIBUSL fix on ULTRA2 or newer controllers.
Older controllers seem to be confused by this.

In target mode, ignore PHASEMIS during data phases.
This bit seems to be flakey on U160 controllers acting
in target mode.

aic7xxx_pci.c:
Add support for the 29160C CPCI adapter.

Add definitions for subvendor ID information
available for devices with the "9005" vendor id.
We currently use this information to determine
if a multi-function device doesn't have the second
channel hooked up on a board.

Add rudimentary power mode code so we can put the
controller into the D0 state. In the future this
will be an OSM callback so that in FreeBSD we don't
duplicate functionality provided by the PCI code.
The powerstate code was added after I'd completed
my regression tests on this code.

Only capture "left over BIOS state" if the POWRDN
setting is not set in HCNTRL.

In target mode, don't bother sending incremental
CRC data.

aic7xxx.c:
Shutdown the card when a catastrophic error occurs. This quenches
any interrupts stemming from the card.

aic7xxx_inline.h:
Return instead of processing additional interrupt state
after handling a catastrophic error. We now shutdown the
chip in this case in the hopes that the system can live
without this controller. The shutdown process invalidates any
other interrupt state.

aic7xxx.seq:
Only attempt to clear SCSIBUSL on Ultra2 controllers. The
clearing is workaround for a selection timeout bug on U2/U160
controllers and happens to be illegal on aic7770 (EISA/VL)
controllers.

Sync Perforce IDs, add tranceiver state change support, and correct
numerous error recovery buglets.

Many thanks to Tor Egge for his assistance in diagnosing problems with
the error recovery code.

aic7xxx.c:
Report missed bus free events using their own sequencer interrupt
code to avoid confusion with other "bad phase" interrupts.

Remove a delay used in debugging. This delay could only be hit
in certain, very extreme, error recovery scenarios.

Handle transceiver state changes correctly. You can now
plug an SE device into a hot-plug LVD bus without hanging
the controller.

When stepping through a critical section, panic if we step
more than a reasonable number of times.

After a bus reset, disable bus reset interupts until we either
our first attempt to (re)select another device, or another device
attemps to select us. This removes the need to busy wait in
kernel for the scsi reset line to fall yet still ensures we
see any reset events that impact the state of either our initiator
or target roles. Before this change, we had the potential of
servicing a "storm" of reset interrupts if the reset line was
held for a significant amount of time.

Indicate the current sequencer address whenever we dump the
card's state.

aic7xxx.reg:
Transceiver state change register definitions.

Add the missed bussfree sequencer interrupt code.

Re-enable the scsi reset interrupt if it has been
disabled before every attempt to (re)select a device
and when we have been selected as a target.

When being (re)selected, check to see if the selection
dissappeared just after we enabled our bus free interrupt.
If the bus has gone free again, go back to the idle loop
and wait for another selection.

Note two locations where we should change our behavior
if ATN is still raised. If ATN is raised during the
presentation of a command complete or disconnect message,
we should ignore the message and expect the target to put
us in msgout phase. We don't currently do this as it
requires some code re-arrangement so that critical sections
can be properly placed around our handling of these two
events. Otherwise, we cannot guarantee that the check of
ATN is atomic relative to our acking of the message in
byte (the kernel could assert ATN).

Only set the IDENTIFY_SEEN flag after we have settled
on the SCB for this transaction. The kernel looks at
this flag before assuming that SCB_TAG is valid. This
avoids confusion during certain types of error recovery.

Add a critical section around findSCB. We cannot allow
the kernel to remove an entry from the disconnected
list while we are traversing it. Ditto for get_free_or_disc_scb.

aic7xxx_freebsd.c:
Only assume that SCB_TAG is accurate if IDENTIFY_SEEN is
set in SEQ_FLAGS.

Fix a typo that caused us to execute some code for the
non-SCB paging case when paging SCBs. This only occurred
during error recovery.

aic7xxx.c:
When restarting the sequencer, ensure that the SCBCNT register
is 0. A non-zero count will prevent the setting of the CCSCBDIR
bit in any future dma operations. The only time CCSCBCNT would
be non-zero is if we happened to halt the dma during a reset,
but even that should never happen. Better safe than sorry.

When a command completes before the target responds to an
ATN for a recovery command, we now notify the kernel so that
any recovery operation requeued in the qinfifo can be removed
safely. In the past, we did this in ahc_done(), but ahc_done()
may be called without the card paused. This also avoids a
recursive call to ahc_search_qinifo() which could have occurred if
ahc_search_qinififo() happened to be the routine to complete
a recovery action.

Fix 8bit math used for adjusting the qinfifo. The index must
be wrapped properly within the 256 entry array. We rely on the
fact that qinfifonext is a uint8_t in most cases to handle
this wrap, but we missed a few spots where the resultant
calculation was promoted to an int.

Change the way that we deal with aborting the first or second
entry from the qinfifo. We now swap the first entry in the
qinfifo with the "next queued scb" to force the sequencer
to see an abort collision if we ever touch the qinififo while
the sequencer is mid SCB dma.

aic7xxx.reg:
Add new MKMSG_FAILED sequencer interrupt. This displaced
the BOGUS_TAG interrupt used in some previous sequencer code
debugging.

aic7xxx.seq:
Increment our position in the qinfifo only once the dma
is complete and we have verified that the queue has not
been changed during our DMA. This simplifies code in the
kernel.

Protect against "instruction creep" when issuing a pausing
sequencer interrupt. On at least the 7890/91/96/97, the
sequencer will coast after issuing the interrupt for up
to two instructions. In the past we delt with this by
using carefully placed nops. Now we call a routine to
issue the interrupt followed by a nop and a ret.

Tell the kernel should an SCB complete with the MK_MESSAGE
flag still set. This means the target ignored our ATN request.

Clear the channel twice as we exit the data phase. On the
aic7890/91, the S/G preload logic may require the second
clearing to get the last S/G out of the FIFO.

aic7xxx_freebsd.c:
Don't bother searching the qinfifo for a doubly queued
recovery scb in ahc_done. This case is handled by the
core driver now.

Free the path used to issue async callbacks after the callback
is complete.

aic7xxx_inline.h:
Split the SCB queue routine into a routine that swaps
the SCB with the "next queued SCB" and a routine that
calls the swapping routine and notifies the card of
the new SCB. The swapping routine is now also used by
ahc_search_qinfifo.

aic7xxx.c:
Filter incoming transfer negotiation requests to ensure they
never exceed the settings specified by the user.

In restart sequencer attempt to deal with a bug in the aic7895.
If a third party reset occurs at just the right time, the
stack register can lock up. When restarting the sequencer
after handling the SCSI reset, poke SEQADDR1 before resting
the sequencers program counter.

When something strange happens, dump the card's transaction
state via ahc_dump_card_state(). This should aid in debugging.

Handle request sense transactions via the QINFIFO instead of
attaching them to the waiting queue directly. The waiting
queue consumes card SCB resources and, in the pathological case
of every target on the bus beating our selection attemps and
issuing a check condition, could have caused us to run out
of SCBs. I have never seen this happen, and only early
cards with 3 or 4 SCBs had any real chance of ever getting
into this state.

Add additional sequencer interrupt codes to support firmware
diagnostics. The diagnostic code is enabled with the
AHC_DEBUG_SEQUENCER kernel option.

Make it possible to switch into and out of target mode on
the fly. The card comes up by default as an initiator but
will switch into target mode as soon as an enable lun operation
is performed. As always, target mode behavior is gated
by the AHC_TMODE_ENABLE kernel option so most users will
not be affected by this change.

In ahc_update_target_msg_request(), also issue a new
request if the ppr_options have changed.

Never issue a PPR as a target. It is forbidden by the spec.

Correct a bug in ahc_parse_msg() that prevented us from
responding to PPR messages as a target.

Mark SCBs that are on the untagged queue with a flag instead
of checking several fields in the SCB to see if the SCB should
be on the queue. This makes it easier for things like automatic
request sense requests to be queued without touching the
untagged queues even though they are untagged requests.

When dealing with ignore wide residue messages that occur
in the middle of a transfer, reset HADDR, not SHADDR for
non-ultra2 chips. Although SHADDR is where the firmware
fetches the ending transfer address for a save data pointers
request, it is readonly. Setting HADDR has the side effect
of also updating SHADDR.

Cleanup the output of ahc_dump_card_state() by nulling out the
free scb list in the non-paging case. The free list is only
used if we must page SCBs.

Correct the transmission of cdbs > 12 bytes in length. When
swapping HSCBs prior to notifing the sequencer of the new
transaction, the bus address pointer for the cdb must also
be recalculated to reflect its new location. We now defer
the calculation of the cdb address until just before queing
it to the card.

When pulling transfer negotiation settings out of scratch
ram, convert 5MHz/clock doubled settings to 10MHz.

Add a new function ahc_qinfifo_requeue_tail() for use by
error recovery actions and auto-request sense operations.
These operations always occur when the sequencer is paused,
so we can avoid the extra expense incurred in the normal
SCB queue method.

Use the BMOV instruction for all single byte moves on
controllers that support it. The bmov instruction is
twice as fast as an AND with an immediate of 0xFF as
is used on older controllers.

Correct a few bugs in ahc_dump_card_state(). If we have
hardware assisted queue registers, use them to get the
sequencer's idea of the head of the queue. When enumerating
the untagged queue, it helps to use the correct index for
the queue.

aic7xxx.h:

Indicate via a feature flag, which controllers can take
on both the target and the initiator role at the same time.

Add the AHC_SEQUENCER_DEBUG flag.

Add the SCB_CDB32_PTR flag used for dealing with cdbs
with lengths between 13 and 32 bytes.

Add new prototypes.

aic7xxx.reg:
Allow the SCSIBUSL register to be written to. This is
required to fix a selection timeout problem on the 7892/99.

Cleanup the sequencer interrupt codes so that all debugging
codes are grouped at the end of the list.

Correct the definition of the ULTRA_ENB and DISC_DSB locations
in scratch ram. This prevented the driver from properly honoring
these settings when no serial eeprom was available.

Remove an unused sequencer flag.

aic7xxx.seq:
Just before a potential select-out, clear the SCSIBUSL
register. Occasionally, during a selection timeout, the
contents of the register may be presented on the bus,
causing much confusion.

Add sequencer diagnostic code to detect software and or
hardware bugs. The code attempts to verify most list
operations so any corruption is caught before it occurs.
We also track information about why a particular reconnection
request was rejected.

Don't clobber the digital REQ/ACK filter setting in SXFRCTL0
when clearing the channel.

Fix a target mode bug that would cause us to return busy
status instead of queue full in respnse to a tagged transaction.

Cleanup the overrun case. It turns out that by simply
butting the chip in bitbucket mode, it will ack any
bytes until the phase changes. This drasticaly simplifies
things.

Prior to leaving the data phase, make sure that the S/G
preload queue is empty.

Remove code to place a request sense request on the waiting
queue. This is all handled by the kernel now.

Change the semantics of "findSCB". In the past, findSCB
ensured that a freshly paged in SCB appeared on the disconnected
list. The problem with this is that there is no guarantee that
the paged in SCB is for a disconnected transation. We now
defer any list manipulation to the caller who usually discards
the SCB via the free list.

Inline some busy target table operations.

Add a critical section to protect adding an SCB to
the disconnected list.

aic7xxx_freebsd.c:
Handle changes in the transfer negotiation setting API
to filter incoming requests. No filtering is necessary
for "goal" requests from the XPT.

Set the SCB_CDB32_PTR flag when queing a transaction with
a large cdb.

In ahc_timeout, only take action if the active SCB is
the timedout SCB. This deals with the case of two
transactions to the same device with different timeout
values.

Use ahc_qinfifo_requeu_tail() instead of home grown
version.

aic7xxx_inline.h:
Honor SCB_CDB32_PTR when queuing a new request.

aic7xxx_pci.c:
Use the maximum data fifo threshold for all chips.

Clean up error recovery code:

aic7xxx.c:
In target mode, reset the TQINPOS on every restart of the sequencer.
In the past we did this only during a bus reset, but there are other
reasons the sequencer might be reset.

In ahc_clear_critical_section(), disable pausing chip interrupts while
we step the sequencer out of a critical section. This avoids the
possibility of getting a pausing interrupt (unexpected bus free,
bus reset, etc.) that would prevent the sequencer from stepping.

Send the correct async notifications in the case of a BDR or bus reset.

In ahc_loadseq(), correct the calculation of our critical sections.
In some cases, the sections would be larger than needed.

aic7xxx.h:
Remove an unused SCB flag.

aic7xxx.seq:
MK_MESSAGE is cleared by the kernel, there is no need to waste
a sequencer instruction clearing it.

aic7xxx_freebsd.c:
Go through the host message loop instead of issuing a single
byte message directly in the ahc_timeout() case where we
are currently on the bus to the device. The effect is the same,
but this way we get a nice printf saying that an expected BDR
was delivered instead of an unexpected bus free.

If we are requeuing an SCB for an error recovery action, be sure
to set the DISCONNECTED flag in the in-core version of the SCB.
This ensures that, in the SCB-paging case, the sequencer will
still recognize the reselection as valid even if the version
of the SCB with this flag set was never previously paged out
to system memory. In the non-paging case, set the MK_MESSAGE
flag in SCB_CONTROL directly.

aic7xxx_pci.c:
Enable the Memeory Write and Invalidate bug workaround for
all aic7880 chips with revs < 1. This bug is rarely triggered
in FreeBSD as most transfers end on cache-aligned boundaries,
but a recheck of my references indicates that these chips
are affected.

Convert the driver to use a single DMA for fetching new commands instead
of two (one to access the circular input fifo, the other to get the SCB).
This costs us a command slot so the driver can now only queue 254
simultaneous commands.

Have the kernel driver honor critical sections in sequencer code.

When prefetching S/G segments only pull a cacheline's worth but
never less than two elements. This reduces the impact of the
prefetch on the main data transfer when compared to the 128
byte fetches the driver used to do.

Add "bootverbose" logging for transfer negotiations.

Correct a bug in ahc_set_syncrate() that would prevent an update
of the sync parameters if only the ppr_options had changed.

Correct locking for calls to ahc_free_scb(). ahc_free_scb() is no
longer protected internally to simplify ports to other platforms.

Make sure we unfreeze our SIMQ if a resource shortage has occurred
and an SCB is been freed.

ahc_pci.c:
Turn on cacheline streaming for all controllers that support it.

Clarify diagnostic messages about PCI interrupts.

Use quoted includes instead of full path references inside the aic7xxx
sequencer files. Different platforms place the included files in different
locations and it is easier to modify the include path passed as arguments
to the assembler than adding #ifdef support to the assembler.

Remove a spurious 'nop' instruction.

Move aicasm to its own subdirectory.

Separate our platform independent hooks from core driver functionality
shared between platforms (FreeBSD and Linux at this time).

Add sequencer workarounds for several chip->chipset interactions.

Correct external SCB corruption problem on aic7895 based cards (3940AUW).

Lots of cleanups resulting from the port to another OS.

ahc_pci.c:
Disable "cache line streaming" for aic7890/91 Rev A chips. I
have never seen these chips fail using this feature, but
some of Adaptec's regression tests have.

Explicitly set "cache line streaming" to on for aic7896/97
chips. This was happening before, but this documents the
fact that these chips will not function correctly without
CACHETHEEN set.

aic7xxx.h:
Add new bug types.

Fix a typo in a comment.

aic7xxx.reg:
Add a definition for the SHVALID bit in SSTAT3 for Ultra2/3
chips. This bit inicates whether the bottom most (current)
element in the S/G fifo has exhausted its data count.

aic7xxx.seq:
Be more careful in how we turn off the secondary DMA channel.
Being less careful may hang the PCI bus arbitor that negotiates
between the two DMA engines.

Remove an unecessary and incorrect flag set operation in
the overrun case.

On Ultra2/3 controllers, clear the dma FIFO before starting
to handle an overrun. We don't want any residual bytes from
the beginning of the overrun to cause the code that shuts
down the DMA engine from hanging because the FIFO is not
(and never will be) empty.

If the data fifo is empty by the time we notice that a
read transaction has completed, there is no need to
hit the flush bit on aic7890/91 hardware that will not
perform an auto-flush. Skip some cycles by short circuiting
the manual flush code in this case.

When transitioning out of data phase, make sure that we
have the next S/G element loaded for the following
reconnect if there is more work to do. The code
would do this in most cases before, but there was
a small window where the current S/G element could
be exhausted before our fetch of the next S/G element
completed. Since the S/G fetch is already initiated
at this point, it makes sense to just wait for the
segment to arrive instead of incuring even more latency
by canceling the fetch and initiating it later.

Fast path the end of data phase handling for the last
S/G segment. In the general case, we might have
worked ahead a bit by stuffing the S/G FIFO with
additional segments. If we stop before using them
all, we need to fixup our location in the S/G stream.
Since we can't work past the last S/G segment, no
fixups are ever required if we stop somewhere in
that final segment.

Fix a little buglet in the target mode dma bug handler.
We were employing the workaround in all cases instead
of only for the chips that require it.

Fix the cause of SCB timeouts and possible "lost data"
during read operations on the aic7890. When sending
a data on any Ultra2/3 controller, the final segment
must be marked as such so the FIFO will be flushed and
cleaned up correctly when the transfer is ended. We
failed to do this for the CDB transfer and so, if
the target immediately transfered from command to data
phase without an intervening disconnection, the first
segment transferred would be any residual bytes from
the cdb transfer. The Ultra160 controllers for some
reason were not affected by this problem.

Many Thanks to Tor Egge for bringing the aic7890 problem
to my attention, providing analysis, as well as a mechanism
to reproduce the problem.

aic7xxx.c:
Correct the BUILD_TCL macro. It was placing the target id
in the wrong bits. This was only an issue for adapters that
do not perform SCB paging (aha-3940AUW for instance).

Don't bother inlining ahc_index_busy_tcl. It is never
used in a performance critical path and is a bit chunky.

Correct ahc_index_busy_tcl to deal with "busy target tables"
embedded in the latter half of 64byte SCBs.

Don't initialize the busy target table to its empty state
until after we have finished extracting configuration
information from chip SRAM. In the common case of using
16 bytes of chip SRAM to do untagged target lookups,
we were trashing the last 8 targets configuration data.
(actually only target 8 because of the bug in the
BUILD_TCL macro).

Cram the "bus reset delivered" message back under bootverbose.

Fix the cleanup of the SCB busy target table when aborting
commands. If the lun is wildcarded, we must loop through
all possible luns.

aic7xxx.h:
Only bother supporting 64 luns right now. It doesn't seem
like either this driver or any peripherals will be doing
information unit transfers (where the lun number is a
32 bit integer) any time soon.

aic7xxx.seq:
Fix support for the aic7895. We must flush the data
FIFO if performing a manual transfer that is not
a multiple of 8 bytes. We were doing this quite
regularly for embedded cdbs.

Manaually flush the fifo on earlier adapters when
dealing with embedded cdbs too. We were stuffing
the FIFO with 16 bytes instead, but triggering
the flush is more efficient and allows us to
remove two instructions from the "copy_to_fifo"
routine.

o Convert to <inttypes.h> style fixed sized types to facilitate porting to
other systems.

o Normalize copyright text.

o Clean up probe code function interfaces by passing around a single
structure of common arguments instead of passing "too many" args
in each function call.

o Add support for the AAA-131 as a SCSI adapter.

o Add support for the AHA-4944 courtesy of "Matthew N. Dodd" <winter@jurai.net

o Correct manual termination support for PCI cards. The bit definitions
for manual termination control in the SEEPROM were incorrect.

o Add support for extracting NVRAM information from SCB 2 for BIOSen
that use this mechanism to pass this data to OS drivers.

o Properly set the STPWLEVEL bit in PCI config space based on the
setting in an SEEPROM.

o Go back to useing 32byte SCBs for all controllers. The current
firmware allows us to embed 12byte cdbs on all controllers in
a 32byte SCB, and larger cdbs are rarely used, so it is a
better use of this space to offer more SCBs (32).

o Add support for U160 transfers.

o Add an idle loop executed during data transfers that prefetches
S/G segments on controllers that have a secondary DMA engine
(aic789X).

o Improve the performance of reselections by avoiding an extra
one byte DMA in the case of an SCB lookup miss for the reselecting
target. We now keep a 16byte "untagged target" array on the card
for dealing with untagged reselections. If the controller has
external SCB ram and can support 64byte SCBs, then we use an
"untagged target/lun" array to maximize concurrency. Without
external SCB ram, the controller is limited to one untagged
transaction per target, auto-request sense operations excluded.

o Correct the setup of the STPWEN bit in SXFRCTL1. This control
line is tri-stated until set to one, so set it to one and then
set it to the desired value.

o Add tagged queuing support to our target role implementation.

o Handle the common cases of the ignore wide residue message
in firmware.

o Add preliminary support for 39bit addressing.

o Add support for assembling on big-endian machines. Big-endian
support is not complete in the driver.

o Correctly remove SCBs in the waiting for selection queue when
freezing a device queue.

o Now that we understand more about the autoflush bug on the
aic7890, only use the workaround on devices that need it.

o Add a workaround for the "aic7890 hangs the system when you
attempt to pause it" problem. We can now pause the aic7890
safely regardless of what instruction it is executing.

o Correct the offsets into the syncrate table for paritcular
negotiation features (DT, ULTRA2, ULTRA, FAST). The offsets
where not properly updated when the DT entry was added and so
the driver could attempt to negotiate a speed faster than that
supported by the target device or even requested by the user
via SCSI-Select settings. *

o Update the target mode incoming command queue kernel index value
ever 128 commands instead of 32. This means that the kernel will
always try to keep its index (as seen on the card - the kernel may
actually have cleared more space) 128 commands ahead of where the
sequencer is adding entries.

o Use the HS_MAILBOX register instead of the KERNEL_TQINPOS location
in SRAM to indicate the kernel's target queue possition on Ultra2
cards. This avoids the "pause bug" on these cards and also turns
out to be much more efficient.

o When enabling or disabling a particular target id for target mode,
make sure that the taret id in the SCSIID register does not
reference an ID that is not to receive target selections. This
is only an issue on chips that support the multiple target id
feature where the value in SCSIID will still affect selection
behavior regardless of the values in the target id bit field
registers.

o Remove some target mode debugging printfs.

o Make sure that the sense length reported in ATIO commands is
always zero. This driver does not, yet, report HBA generated
sense information for accepted commands.

o Honor the CAM_TIME_INFINITY and CAM_TIME_DEFAULT values for
the CCB timeout field.

o Make the driver compile with AHC_DEBUG again.

* Noticed by: Andrew Gallatin<gallatin@cs.duke.edu>

Kill the "unpause_always" argument to unpause_sequencer(). The reasons
for optimizing the unpause operation no-longer exist, and this is much
safer.

When restarting the sequencer, reconstitute the free SCB list on the card.
This deals with a single instruction gap between marking the SCB as free
and actually getting it onto the free list.

Reduce the number of transfer negotiations that occur. In the past, we
renegotiated after every reported check condition status. This ensures
that we catch devices that have unexpectidly reset. In this situation,
the target will always report the check condition before performing a
data-phase. The new behavior is to renegotiate for any check-condition where
the residual matches the orginal data-length of the command (including
0 length transffers). This avoids renegotiations during things like
variable tape block reads, where the check condition is reported only
to indicate the residual of the read.

Revamp the parity error detection logic. We now properly report and
handle injected parity errors in all phases. The old code used to hang
on message-in parity errors.

Correct the reporting of selection timeout errors to the XPT. When
a selection timeout occurs, only the currently selecting command
is flagged with SELTO status instead of aborting all currently active
commands to that target.

Fix flipped arguments in ahc_match_scb and in some of the callers of this
routine. I wish that gcc allowed you to request warnings for enums passed
as ints.

Make ahc_find_msg generically handle all message types.

Work around the target mode data-in wideodd bug in all non-U2 chips.
We can now do sync-wide target mode transfers in target mode across the
hole product line.

Use lastphase exclusively for handling timeouts. The current phase
doesn't take the bus free state into account.

Fix a bug in the timeout handler that could cause corruption of the
disconnected list.

When sending an embedded cdb to a target, ensure that we start on a
quad word boundary in the data-fifo. It seems that unaligned stores
do not work correctly.

Update copyrights to Y2K.

93cx6.c:
Make the SRAM dump output a little prettier.

aic7xxx.c:
Store all SG entries into our SG array in kernel space.
This makes data-overrun and other error reporting more
useful as we can dump all SG entries. In the past,
we only stored the SG entries that the sequencer might
need to access, which meant we skipped the first element
that is embedded into the SCB.

Add a table of chip strings and replace ugly switch
statements with table lookups.

Add a table with bus phase strings and message reponses
to parity errors in those phases. Use the table to
pretty print bus phase messages as well as collapse
another switch statement.

Fix a bug in target mode that could cause us to unpause
the sequencer early in bus reset processing.

Add the 80MHz/DT mode into our syncrate table. This
rate is not yet used or enabled.

Correct some comments, clean up some code...

aic7xxx.h:
Add U160 controller feature information.

Add some more bit fields for various SEEPROM formats.

aic7xxx.reg:
Add U160 register and register bit definitions.

aic7xxx.seq:
Make phasemis state tracking more straight forward. This
avoids the consumption of SINDEX which is a very useful register.

For the U160 chips, you must use the 'mov' instruction to
update DFCNTRL. Using 'or' to set the PRELOADED bit is
completely ineffective.

At the end of the command phase, wair for our ACK signal
to de-assert before disabling the SCSI dma engine. For
slow devices, this avoids clearing the ACK before the
other end has had a chance to see it and lower REQ.

Simplify my copyright license terms.

aic7xxx.c:
Add a function for sucking firmware out of the controller
prior to reset.

Remove some inline bloat from functions that should not have
been inlined.

During initialization, wait 1ms after the chip reset before
touching any registers. You can get machine checks on certain
architectures (Atari I think?) without the delay.

Return CAM_REQ_CMP for external BDR requests instead
of CAM_BDR_SENT.

Bump some messages to bootverbose levels above 1.

Don't clear any negotiated sync rate if the target rejects
a WDTR message. The sync rate is only cleared if the target
accepts a WDTR message.

Fix a small bug in the mesgin handling code that could cause
us to believe that we had recieved a message that was actually
received by another target. This could only confuse us in
some very rare transmission negotiation scenarios.

Remove some unecessary cleanup of residual information after
a residual is reported. The sequencer does this when the
command is queued now.

Work around a defect in the FIFOEMP status bit of Ultra2 class
aic7xxx parts. This problem could result in data corruption
during periods of my PCI bus load by busmasters other than the
aic7xxx.

Many thanks to Andrew Gallatin <gallatin@cs.duke.edu> for characterizing
the symptoms of this problem and testing this fix.

$Id$ -> $FreeBSD$

aic7xxx.c:
Honor the 'bus reset at startup' option now that the XPT properly
handles transfer negotiation in this scenario.

Honor the sync rate settings on Ultra2 controllers. We would
always negotiate at the fastest speed. Oops.

aic7xxx.h:
Whitespace.

aic7xxx.seq:
Fix a minor nit that would cause the controller to miss the update
of the negotiation required bitmask causing the negotiation to
be delayed by a command.

Better workaround for aic7890 chip bug. Use the HS_MAILBOX register to
tell the sequencer to pause itself for a target msg variable update. This
avoids the pause race entirely as HS_MAILBOX can be accessed without
pausing the chip.

3.2 Merge candidate.

Use TCL_CHANNEL/SCSI_ID/etc. macros in more locations.

Don't mess with the IRQMS bit in the host control register unless
we are an aic7770 chip.

Use calling context to determine if the card is already paused when
we update the target message request bit field in controller scratch
ram. Looking at the paused bit in the HCNTRL register opened up a
race condition.

Insert delays in the target message request update routine as a temporary
work around for what looks like a chip bug. I'm still investigating this
one.

Fix the Abort/Abort Tag/BDR handler to pull its message from the message
buffer in our softc instead of attempting to get it from a register on
the controller. The message is never recorded by the controller in the
new message scheme.

Don't rely on having an SCB when a BDR occurs. We can issue these during
invalid reconnects to.

Fix a few cases where we were restarting the sequencer but then still
falling out of a switch statement to unpause the sequencer again.
This could cause us to mess up sequencer state if it generated another
pausing interrupt between the time of the restart and unpause.

Kill the 'transceiver settle' loop during card initialization. I
failed to realize that a controller that is not connected to any
cables will never settle or enable the SCSI transceivers at all.
The correct solution is to monitor the IOERR interrupt which indicates
that the transceiver state has changed (UW<->LVD).

Modify the aic7xxx assembler to properly echo input when stdin is not
a tty.

Keep track of negotiated transfer parameters for each initiator<->target
connection.

Clean up support for devices featuring the multiple target SCSI ID feature.
On aic7890/91/96/97 chips, we can now assume the target role on multiple
target ids simultaneously. Although these chips also have sufficient
instruction space to hold to support the initiator and target role at the
same time, the initiator role is currently disabled as it will conflict
(chip design restriction) with the multi-tid feature. I'll probably add
a nob to enable the initiator (there-by disabling multi-tid) some time
in the future.

Return queue full or busy, depending on the tagged nature of the incoming
request, if our command input queue fills up in host memeory.

Deal with accept target I/O resource shortages.

If we get an underrun on a transaction that wasn't supposed to transmit
any data, don't attempt to print out the S/G list. The code would
run until hitting a non-present page. (oops)

Ensure that the ACK from the last information transfer phase has been
de-asserted by the initiator before changing phase or releasing the bus.
Corrects a SCSI specification violation in target mode.

Add support for routing initiator transactions to disabled luns to the
black hole device. The controller will now only accept selections if
the black hole device is present and some other target/lun is enabled
for target mode.

Handle the IGNORE WIDE RESIDUE message. This support has not been tested.

Checkpoint work on handling ABORT, BUS DEVICE RESET, TERMINATE I/O PROCESS,
and CLEAR QUEUE messages as a target.

Fix a few problems with tagged command handling in target mode.

Wait until the sync offset counter falls to 0 before changing phase
after a data-in transfer completes as the DMA logic seems to indicate
transfer complete as soon as our last REQ is issued.

Simplify some of the target mode message handling code in the sequencer.

Fix a few problems with handling rejected transfer negotiation messages.

Use the host message loop for any unknown message types instead of performing
a reject message in the sequencer. Pass reject messages to the host
message loop too which frees up a sequencer interrupt type slot.

Default to issuing a bus reset if initiator mode is enabled. It seems
that the reset scsi bus bit is not defined in the same location for
all aic78xx BIOSes, so attempting to honor this setting will have to
wait until I get more information on how to detect it.

Nuke some unused variables.

Perform a save data pointers operation if a data transfer was performed
in target mode, but we are not completing the command.

Use a template of allowed bus arbitration phases to selectively and
dynamically enable/disable initiator or target (re)selection.

Properly handle timeouts for target role transactions - just go to the
bus free state and report the error to the peripheral driver.

Checkpoint support for the XPT_ABORT_CCB function code. This currently
handles the accept tio and immediate notify ccb types, but does not
handle the continue target I/O or SCSI I/O ccb types. This is enough
to handle dynamic target enable/disable events.

Clean up the SCSI reset code so that we perform at most 1 SCSI bus
reset at initialization, the reset requested by the XPT layer.

Revamp the way that exceptional message handling is performed so that it
is more robust and common code can be used for both the target and iniator
roles. The mechanism for tracking negotiation state has also been simplified.

Add support for sync/wide negotiation in target mode and fix many of
the target mode bugs running at higher speeds uncovered. Make a first
stab at getting all of the bus skew delays correct. Sync+Wide dataout
transfers still cause problems, but this may be an initiator problem.

Ensure that we exit BITBUCKET mode if the controller is restarted.

Add support for target mode only firmware downloads. This has been
tested on the aic7880, but should mean that we can perform target mode
on any aic7xxx controller. Mixed mode (initiator and target roles in
the same firmware load) is currently only supported on the aic7890, but
with optimization, may fit on chips with less instruction space.

Change the delivery mechanism for incoming target commands. We now
use a 256 entry ring buffer of descriptersfor this purpose. This allows
the use of a simple 8bit counter in the sequencer code for tracking start
location.

Entries in the ring buffer now contain a "cmd_valid" byte at their tail.
As an entry is serviced, this byte is cleared by the kernel and set by
the sequencer during its dma of a new entry. Since this byte is the last
portion of the command touched during a dma, the kernel can use this
byte to ensure the command it processes is completely valid.

The new command format requires a fixed sized DMA from the controller
to deliver which allowed for additional simplification of the sequencer
code. The hack that required 1 SCB slot to be stolen for incoming
command delivery notification is also gone.

Correct twin channel operation.

Massive overhaul of the aic7xxx driver:
- Convert to CAM
- Use a new DMA based queuing and paging scheme
- Add preliminary target mode support
- Add support for the aic789X chips
- Take advantage of external SRAM on more controllers.
- Numerous bug fixes and performance improvements.

Some revisions of the aic7880 have a problem where, if the
data fifo is full, but the PCI input latch is not empty,
HDMAEN cannot be cleared. The fix used here is to attempt
to drain the data fifo until there is space for the input
latch to drain and HDMAEN de-asserts.

This is a 1 instruction fix, so it should have no performance
impact.

Add support to aicasm for "downloaded constants". These are immediate
operands that are set during seqeuncer program download instead of at
assembly time.

Convert the sequencer code to use" downloaded constants" for four run time
constants that vary depending on the board type. This frees up 4 bytes
of sequencer scratch ram space where these constants used to be stored and
also removes the additional instructions required to load their values
into the accumulator prior to using them.

Remove the REJBYTE sram variable. The host driver can just as easly
read the accumulator to get this value.

The scratch ram savings is important as the old code used to clober the
SCSICONF register on 274X cards which sits near the top of scratch ram
space. The SCSICONF register controls bus termination, and clobbering
it is not a good thing. Now we have 4 bytes to spare.

This should fix the reported problems with cards that don't have devices
attached to them failing with a stream of "Somone reset bus X" messages.

Doug Ledford determined the cause of the problem, fixes by me.

Add a spin lock that prevents the sequencer from attempting to add an
entry to the QOUTFIFO when it is full. This should eliminate the
"Timed out while idle" problems that many have reported.

In truth, this is somewhat of a hack. Although are interrupt latency is
low enough that we should be able to always service the queue in time,
since each entry must be passed up to the higher SCSI layer for what can
be a large amount of processing (perhaps even resulting in a new command
being queued) with interrupts disabled, we need this mechanism to avoid
overflow. In the future, these additional tasks will be offloaded to a
software interrupt handler which should make this hack unnecessary.

Modify my copyright notice to allow the sequencer to be used with GPLed
software (aka Linux).

Fix a few bugs in the sequencer assembler.

Make it easy to compiler the assembler with debugging turned on.

The following scenario would result in a bogus residual being reported
if SCB Paging was enabled:

disconnect with more data to transfer
disconnected SCB gets paged out
target reconnects so we page SCB back in
target completes transfer so residual is 0
target disconnects
SCB gets reused but not paged out since the residual is 0 (optimization)
target reconnects so we page the SCB back in
we report a residual because of stale residual information.

The fix for this is to set a flag that forces the SCB to be paged back
up to the host if we page in an SCB with a residual

Pointed out by: Doug Ledford <dledford@dialnet.net>

Revert some changes to the selection and reselection code that were thought
to fix a selection timeout problem.

If we can't find an SCB for the reconnecting target, issue a bus device
reset as the SCSI2 spec suggests.

Add a missing call to "add_scb_to_free_list" in the non paging case. In
the non-paging case, the SCBs don't really need to be on the free list,
but putting them there clears the tag field which is something the recovery
code depends on.

Re-arange the selection and reselection code to hopefully kill the
spurious selection timeouts that have been reported.

aic7xxx.seq:
Be consistant about testing for parity errors after waiting for a
REQ on the bus.

Don't ack the last byte in a transaction until after we've cleared
all target state.

aic7xxx_asm.c:
Test the return value of getopt against -1 not EOF. (Yet another
shameless victum of the style guide being wrong).

Instead of testing for both SELDI and SELDO in SSTAT0 in the poll for work
loop, test for them separately. The bug report from David Malone showed that
even though we had been reselected (SELDI was true), we sat in the poll for
work loop until the selection timeout timer expired. It may be that the
SSTAT0 register doesn't like to have more than one bit tested at a time.
I've seen stranger things than this on these parts.

Add missing Id that was lost when the sequencer file format changed.

When not using SCB paging, we can always directly index the SCB of interest
either by looking it up in the array of pending, per target, untagged
transactions, or by using the tag value passed in during the identify. The
old code only direct indexed for tagged transactions. This makes the
"findSCB" routine only necessary when SCB paging is enabled, so appropriately
conditionalize it. This greatly simplifies the non SCB paging code flow.

Re-arrange the code to upload an SCB to ensure that there is at least
on instruction between the last load into the DFIFO and enabling the DMA.
During back to back SCB DMA, it was possible to hang the card.

aic7xxx.seq:
Stick 4 more, twin channel only, instructions behind
.if ( TWIN_CHANNEL)

aic7xxx_asm.c:
Add the -O options which allows the specification of which options
to include in a program listing. This makes it possible to easily
determine the address of any instruction in the program across
different hardware/option configurations. Updated usage() as well.

Makefile gram.y scan.l sequencer.h symbol.c symbol.h aic7xxx_asm.c:
New sequencer assembler for the aic7xxx adapters. This assembler
performs some amount of register type checking, allows bit
manipulation of symbolic constants, and generates "patch tables"
for conditionalized downloading of portions of the program.
This makes it easier to take full advantage of the different
features of the aic7xxx cards without imposing run time penalies
or being bound to the small memory footprints of the low end
cards for features like target mode.

aic7xxx.reg:
New, assembler parsed, register definitions fo the aic7xxx cards.
This was done primarily in anticipation of 7810 support which
will have a different register layout, but should be able to use
the same assembler. The kernel aic7xxx driver consumes a generated
file in the compile directory to get the definitions of the register
locations.

aic7xxx.seq:
Convert to the slighly different syntax of the new assembler.

Conditionalize SCB_PAGING, ultra, and twin features which shaves
quite a bit of space once the program is downloaded.

Add code to leave the selection hardware enabled during reconnects
that win bus arbitration. This ensures that we will rearbitrate
as soon as the bus goes free instead of delaying for a bit.

When we expect the bus to go free, perform all of the cleanup
associated with that event "up front" and enter a loop awaiting
bus free. If we see a REQ first, complain, but attempt to
continue. This will hopefully address, or at least help diagnose,
the "target didn't send identify" messages that have been reported.

Spelling corrections obtained from NetBSD.

No longer clear all interrupt status when the sequencer is reset. The only
time that we really want to do this is when a bus reset causes the sequencer
to be reset and the kernel driver now handles this case.

Remove some reordering in the select2 routine that wasn't necessary.
It was an experimental fix for a race condition I fixed elsewhere, and
confused the code flow.

Don't bother looping on a parity error in the mesgout loop since we can't
see parity errors on out phases.

Clean up the mesgin_identify code. In the old days, we "snooped" for tag
messages and used this as an indicator of whether or not the target was
using tagged transactions. This forced the sequencer to ack the identify
before determining if a valid SCB matched the target meaning that an abort
message to handle this case might not be seen before the target entered a
data phase. Since we can determin the "tagged-ness" of a target by looking
it up in the array of busy targets (recently introduced), we can determine
this up front simplifying the search code as well as ensuring we can follow
the SCSI specs method for rejecting a reselection.

When an SCB is placed on the free list, set its SCB_TAG to SCB_LIST_NULL.
This makes it much easier for the kernel driver to find active SCBs on the
card during error recovery.

Leave reselections on all the time.
If we are aborting an SCB from findSCB, don't add it back to the free list -
the kernel driver will do this for us.

Back out part 1 of the MCFH that changed $Id$ to $FreeBSD$. We are not
ready for it yet.

Enlarge the message out buffer from 6 to 8 bytes. Now that sync and wide
negotiation messages may be tagged, we were overrunning the old buffer.
The variable that was getting squashed is updated before the message goes
out, causing corrupted SDTR or WDTR messages. Depending on the phases
traversed before message out, this could cause the wrong offset to be
negotiated allowing data overruns to occur. The problem is easier to
detect with wide targets on the chain since the allowed offset is smaller.

Also removed the unnecessary clearing of SPIORDY during the message out
phase. We don't rely on SPIORDY any more.

Clear the DFCNTRL register after every busfree.

When setting the HCNT registers, do so in ascending order.

When performing tagged queueing in non-paging mode, also check the
disconnected bit in the SCB as extra sanity during a reconection.

Make the labels in the DMA routine more sane.

When doing a DMA, if we see the DMADONE condition come true, we can
simply turn of the DMA enable bits in DFCNTRL without testing the FIFO
state as HDONE is true when DMADONE is true and this emplies the FIFO is
empty.

These changes clear up the data overrun error messages and seem to prevent
the "timed out in data-in phase" problems.

Clear the channel after (re)selection instead of once we see the bus go
free.

When we clear SCSIRATE, also clear the FAST20 bit in SXFRCTL0. This also
allowed me to clean up some of the ULTRA code.

ULTRAENB->FAST20 to follow the convention in the Adaptec data books.

Fix the data-overrun code to set both stcnt and hcnt otherwise, the transfer
will just hang until we get a timeout.

Add implicit support for the NOOP message. I've never heard of the driver
issueing a reject for one, but its silly to reject NOOP and who knows how a
device might react.

In the dma routine, check SDONE before cleaing SDMAEN. The data books mention
SDONE possibly being cleared when SDMAEN is reset. Clients of dma now need
to check if SINDEX is cleared to know if a phasemis occured.

Fix some comments to be correct.

In dma_finish, don't disturb the direction bit in DFCNTRL when turning off
host DMAs. The additional test to ensure that the DMA has stopped is also
unnecessary since we've already waited for the DMA to complete.

Update my copyright for the new year.

Add 1997 to my copyright.

Expand the boundaries of a pause disabled region to close of possible race
condition.

Revert a portion of the DMA code to fix false overruns.

Add a missing "add_scb_to_free_list" so we don't leak SCBs.

Change the way DMA is handled during the command phase. Only test on
SDONE, not HDONE.

In the data phase dma handler, mask off just the enable bits instead of
clearing the whole register. Clearing the direction bit could be bad.
Also don't stop a DMA until MREQPEND goes false. Doing this may cause
an ABORT on the PCI bus although I have yet to see this happen.

Add definitions for MREQPEND and the BRDCTL register. The BRDCTL register
is used to handle high byte termination and automatic termination testing.

Clear the SCSI channel after we go to busfree instead of after re/selection.

Only enable reselections once the channel and SCSIRATE have been cleared.

Add a pause block around the test busy code in the non-tagged case to simplify
error recovery in the corner case of aborting an SCB that just got started.

Simplify reselection processing by removing the call to initialize_scsiid.

Clear the scsiseq re/select control bits and setup for catching bogus
busfrees earlier in the re/select process.

Improve the automatic PIO code. It turns out that SPIORDY is not a reliable
hardware condition bit, so use REQINIT intstead. Don't rely on PHASEMIS
either since it can take too long to come true. Use a brute force comparison
instead.

Remove some unnecessary overhead in the command complete processing. It
should be nearly impossible to overflow the QOUTFIFO (worst case 9 command
have to complete with at least 6 of them requiring paging on an aic7850),
so don't take the additional PIO hit to guard against this condition. If we
don't see our interrupt in time, the system has bigger problems elsewhere.
If this ever does happen, the timeout handler will notice and retry the
command.

Make the long-awaited change from $Id$ to $FreeBSD$

This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.

Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.

Re-enable reselections as the first thing after we see a bus free. We seem
to miss reselections from some devices and since the reselection response
timeout is only 200ns, enabling reselections too late may be the cause of our
problem.

Conditionally enable the busfree interrupt to catch unexpected busfrees.
Immediate SCBs, since they always send messages that tell the target to
transition to bus free now rely on the busfree interrupt instead of the
IMMEDDONE sequencer interrupt that was generated before.

Rearrange some code in the message out loop to give ATN a little more time
to drop before we ACK the last byte.

Use SPIORDY instead of REQINIT when snooping for a tag message on a reconnect.
This is done for the same reasons we use SPIORDY in the inb functions.

When going into BITBUCKET mode, turn off HDMAEN in the DFCNTRL register so
that we can "not care" what the value of HCNT is. If HCNT is 0, BITBUCKET
mode won't transfer any data if HDMAEN is set. Seeing as we don't want the
transfer to even think about touching the host, this seems more sane anyway.
Thanks to "Dan Willis" <dan@plutotech.com> for pointing out that this was
a problem.

Change the way Automatic PIO is performed in the mesgin and mesgout phases.
SPIORDY should go active on any REQ of the bus, so testing for REQINIT is
not necessary. It also seems that testing for SPIORDY is more robust then
REQINIT since SPIORDY comes active after REQINIT and PHASEMIS seems to take
some time to come true after REQ is asserted if the phase has changed. Of
course, none of this is documented.

This should give the code savings of my original changes, without breaking the
driver on fast peripherals.

Assert that we have seen an identify or have not disconneccted since the
initial selection when entering the status phase. This is the same assertion
we use for all the other data transfer phases.

Hopefully fix the hangs in the mesgin and mesgout phases that I introduced
last week during some code cleanup. I need to get some of these 12MB/s
drives so I can reproduce these hangs here...

Add a pause disable in the SCB paging case around our manipulation of the
QOUTQCNT variable. This is simply extra sanity.

Set LASTPHASE to P_BUSFREE once we see a busfree so that the kernel driver can
differentiate this from a data out phase.

Fix two problems with SCB Paging.

1) get_free_or_disc_scb was not being passed its argument correctly
in one case

2) Add protection in the form of the QOUTQCNT variable to prevent
overflowing the QOUTFIFO.

This should make SCB Paging work. Really, I mean it now. 8-)

index_untagged_scb should rely solely on the argument passed in SINDEX and
not access SCB_TCL directly. This could have caused problems on twin channel
adapters.

2.2 Candidate.

In data_phase_reinit when I converted the code to use bcopy, I should have
used mvi instead of mov. Luckily this code is most likely never executed
since it is only there for sanity should a target goes into the data phase
twice during a single selection or reselection.

Fix problems dealing with non-tagged devices when SCB paging is enabled.
Mostly this involved changing the semantics of the findSCB routine so that
it could be used at times other than handling a reconnection.

Go back to using DMA to get SCBs down to the adapter.

SCB paging is now handled almost entirely by the sequencer and also uses
DMA. This should make SCB paging at least an order of magnitude more
efficient and vastly simplifies the implementation.

Add a few space optimizations so this code still fits on aic7770 chips.

Update comments.

Bring aic7xxx driver bug fixes from 'SCSI' into current.

Detect and report dataphase overruns. Put the adapter into 'Bit Bucket'
mode when this occurs and allow the target to complete the transaction.
Force a retry on overruns since they are usually caused by termination or
cable problems.

Hopefully fix the parity problem and the hang on message reject for good.

Don't use the auto ATN on parity error feature. It may be the source
of our parity handling problems.

Fix regression. It seems that you need at least one instruction between
seeing SPIORDY and checking for PHASEMIS. My last change turned out to
be less cosmetic then I thought.

Pointed out by: Satoshi Asami <asami@cs.berkeley.edu>,
Faried Nawaz <fn@pain.csrv.uidaho.edu

Merge in changes for NetBSD/OpenBSD.

Cosmetic change to p_mesgout code so that it "looks" the same as what
is done in the inb* routines.
NetBSD/OpenBSD support Submitted by:Noriyuki Soda <soda@sra.co.jp>,
Pete Bentley <pete@demon.net>,
Charles M. Hannum <mycroft@mit.edu>,
Theo de Raadt <deraadt@theos.com>

Fix a race condition in p_mesgout* and inb* code that could allow a
phasemiss to sneak by without detection. This should fix the
Wide/Narrow boot problems that have been reported since this bug
caused the driver ignore a narrow target rejecting wide negotiation.

Correct a botched commit from yesturday. It helps to bring over the
right patch file.<sigh>

Enable/Disable Ultra mode on a per target basis. This allows the driver
to use the full range of settings from 3.6-20MHz on any target.

aic7xxx.seq:
Change #ifdef linux to #ifdef __linux__

aic7xxx_reg.h:
Remove unneeded BOFF_60BCLOCKS
define CHIPRSTACK to be the same as CHIPRST
define RESET_SCSI and CHANNEL_B_PRIMARY bits
All of these aer used during the setup of adapters.

Implement SCB paging. This allows up to 255 active commands on
aic7770 >= Rev E, aic7850, aic7860, aic7870, and ai7880 based controllers.

Make findSCB safer for non-tagged commands when tagged commands are
active on the controller. The symptoms of this problem were
"Overlapped commands attempted" messages during error recovery
attempts.

Compact scratch ram usage. This leaves 8 bytes free for future use.

Clean up some comments.

aic7xxx_reg.h:
Update my copyright.

aic7xxx.seq:
Fix support for the aic7850 by looking only at the relavent bits of the
QINCNT. The 7850 puts random garbage in the high bits and all my attempts
to determine the cause of this failed. This approach does seem to work
around the problem.

Don't trust SCSIPERR to tell us when there is a parity error. On
some revs of the 7870 and the 7880, this bit follows the parity of
the current byte. Instead of using a SEQINT to tell the kernel,
re-enable the standard parity error interrupt since it seems to pause
the sequencer right at the time of the error which is the effect we were
looking for anyway.

aic7xxx_reg.h:
Remove PARITY_ERROR seqeuncer interrupt type, its no longer used.

Define QCOUNTMASK as the SRAM location for the mask to use on the
QINCNT register. QCOUNTMASK is determined by the number of SCBs
supported by the device we're working on.

aic7xxx_asm.c
Properly check the return value of fopen, and define the arg list
in getopt correctly.
Submitted by: Pete Bentley <pete@demon.net>

Reset the DMA control register whenever we reset the sequencer.
Clear LASTPHASE on busfree so the kernel driver can tell that the
sequencer is idle.
Fix some comments to reflect reality.

Performance optimizations. Unroll all bcopies. Use PIO to transfer SCBs
since setting up the DMA is too costly. Restructure for efficiency.

Pause the sequencer when a parity error occurs so that the kernel driver
knows during which phase the error was encountered.

Take a different approach to the SPIORDY race condition. Simply clear
SPIORDY just before we ack on the bus so that there is no chance to
see SPIORDY for the same byte twice.

Make some small modifications so that the Linux aic7xxx driver can use
our sequencer and register definition files verbatum.

Change the inb and outb routines slightly. It seems that waiting for
SPIORDY after polling REQINIT is a bad idea.

aic7xxx.seq:
Add the same type of safeguards we use in the mesg_in phase to the mesg_out
phase.

aic7xxx_reg.h:
Add definitions for the DSCommand register for PCI adapters.

Bring back the more heavy-weight version of the mesgin inb routines. Davidg's
testing made me think that some of the checks were superfluous, but
wcarchive (and Amancio) know better.

The long awaited stability patch set for the aic7xxx driver:

1) Use cpp to preprocess the sequencer code.

2) Convert all "magic numbers" to #defines shared by the sequencer and
kernel driver via the aic7xxx_reg.h file. (The assembler still needs
to be re-written in lex/yacc to allow ~|& type constructions).

3) Raise ATN on parity errors for "in" phases and send an initiator detected
error or message-in parity error message as appropriate.

4) Turn off the reselection hardware from the time or a (re)connection to
busfree. It seems that some fast targets were able to reconnect before
the sequencer was able to see busfree.

5) The message buffer is considered "in-use" when there is a positive length
count. The ACTIVE_MSG flag was unnecesary.

6) Properly set SCB_NEXT_WAITING to SCB_LIST_HEAD in scbs being added to
the waiting scb list. This is a change in how the list code works to
facilitate some planned work in the reset code.

7) The fields in the SCB have be re-arranged to be quad-word aligned.

8) The inb code has been rewritten to catch phasemisses and be more efficient.

9) Go back to "snooping the bus" to determine if the incomming identify
message will be followed by a simple queue message. Its much faster than
doing a search through the SCBs.

10) Implement better tag range checking for incomming tags.

11) Make sdtr_to_rate more accurate (use 25 instead of 24 in calculations -
must have been asleep that night).

12) Rearrange some routines to reduce code complexity and size.

13) Update comments and formatting.

14) Fixed bugs I've forgotten about??

Reviewed by: David Greenman <davidg@FreeBSD.org>

Fix the long dreaded Wide bug and enable WIDEODD for reads.

Only or in CLRCHN in SXFRCTL0. All other bits in this register are
initialized by the kernel driver now.

Set SCSIGO generically before we determine the phase instead of doing it
in each phase routine. Saves a few instructions.

Be more careful in how we deal with SXFRCTL0. Or in the control bits of
interest instead of using mvi. The kernel driver will set the ULTRAEN
bit of SXFRCTL0 if we are using Ultra (20MHz) mode and we don't want to
clobber it.

In sdtr_to_rate divide by two if we are in ultra mode to get the correct
setting since its a 20MHz instead of 10MHz scale.

Clean up the mesgin code to make it easier to read with proceedure lables
that are based on what mesage is being processed instead of just numbers.

Order the tests for incoming message type by level of occurance.

Total rewrite of the dataphase sections of the sequencer. This was done
to replace the very poor, original implementation of Scatter/Gather operations.

Use a bit (that was freed up with the rewrite above) in the SCB control byte
to designate commands that should allow disconnection. The kernel driver
makes this decision now instead of the sequencer since the sequencer can't
do the indexing very efficiently.

This commit drops the sequencer from 426 instructions to 390 most likely
freeing enough space to do a target mode implementation.

Fix two race conditions.

The first could occur because the original code would continue to reset
the SCSIID register while waiting for a selection. This could potentially
conflict with a reconnect since a successfull reconnect will also set the
SCSIID register. The fix is to use a separate wait loop after starting
a selection (as was done a few revisions ago).

The second probably never happens, but it was possible for a target to
reconnect while there was a pending SCB on the waiting list and not get
noticed. The fix was to remove a supurflous check of the scb waiting
list.

Pause the sequencer when message only requests complete. This allows the
kernel driver to know the exact state of the sequencer after a BUS DEVICE
RESET or ABORT completes so it can properly clean up the request.

Change SCB_LIST_NULL to 0xff from 0x10 to allow for 255 commands. This
is needed for 3940 support.

Have tagged commands look to see if a target is "busy" with a non tagged
command before executing. This prevents overlapped tagged and non tagged
commands which can happen since request sense commands are not tagged.

Fixes to the aic7xxx sequencer code and device driver from Justin Gibbs:

1) If a target initiated a sync negotiation with us and happened to chose a
value above 15, the old code inadvertantly truncated it with an "& 0x0f".
If the periferal picked something really bad like 0x32, you'd end up with
an offset of 2 which would hang the drive since it didn't expect to ever
get something so low. We now do a MIN(maxoffset, given_offset).

2) In the case of Wide cards, we were turning on sync transfers after a
sucessfull wide negotiation. Now we leave the offset alone in the per
target scratch space (which implies asyncronous transfers since we initialize
it that way) until a syncronous negotation occurs.

3) We were advertizing a max offset of 15 instead of 8 for wide devices.

4) If the upper level SCSI code sent down a "SCSI_RESET", it would hang the
system because we would end up sending a null command to the sequencer. Now
we handle SCSI_RESET correctly by having the sequencer interrupt us when it
is about to fill the message buffer so that we can fill it in ourselves.
The sequencer will also "simulate" a command complete for these "message only"
SCBs so that the kernel driver can finish up properly. The cdplay utility
will send a "SCSI_REST" to the cdplayer if you use the reset command.

5) The code that handles SCSIINTs was broken in that if more than one type
of error was true at once, we'd do outbs without the card being paused.
The else clause after the busfree case was also an accident waiting to
happen. I've now turned this into an if, else if, else type of thing, since
in most cases when we handle one type of error, it should be okay to ignore
the rest (ie if we have a SELTO, who cares if there was a parity error on
the transaction?), but the section should really be rewritten after 2.0.5.
This fix was the least obtrusive way to patch the problem.

6) Only tag either SDTR or WDTR negotiation on an SCB. The real problem is
that I don't account for the case when an SCB that is tagged to do a particular
type of negotiation completes or SELTOs (selection timeout) without the
negotiation taking place, so the accounting of sdtrpending and wdtrpending
gets screwed up. In the wide case, if we tag it to do both wdtr and sdtr,
it only performs wdtr (since wdtr must occur first and we spread out the
negotiation over two commands) so we always have sdtrpending set for that
target and we never do a real SDTR. I fill properly fix the accounting
after 2.0.5 goes out the door, but this works (as confirmed by Dan) on
wide targets.

Other stuff that is also included:

1) Don't do a bzero when recycling SCBs. The only thing that must explicitly
be set to zero is the scb control byte which is done in ahc_get_scb. We also
need to set the SG_list_pointer and SG_list_count to 0 for commands that do
not transfer data.

2) Mask the interrupt type printout for the aic7870 case. The bit we were
using to determine interrupt type is only valid for the aic7770.


Submitted by: Justin Gibbs

Restructure the arbitration loop to allow for reselections that win out over
the adapter's selections. Many fast periferals were getting upset when
the sequencer decided to rearbitrate after the device had already won
arbitration. This also forced the creation of a list threaded through
the SCBs (since we don't have enough space anywhere else) of commands that
are awaiting reselection. This list is run down before any new transactions
from the input queue are allowed. The list is appened to whenever we begin
a selection (simple case since the selecting device is always at the head)
and by the kernel driver whenever a request sense occurs. In the common
case, the list is only one element long, but when a reselection wins out
over a selection and that reselection generates a request sense, the
outstanding selection required for the retreval of the sense code grows
the list. On machines with many targets, this might cause the list to grow
large, so this solution, which will allow up to the maximum number of I/O
requests capible of the card elements in the list, was chosen. The list
manipulation is trivial and adds three sequencer instructions of overhead
to the selection phase.

This fixes the "target busy" errors from micropolis drives and the bursty
I/O problem when performing I/O between a Quantum Grand Prix and any other
device. I anticipate that this will correct many of the problems that
have been reported with this driver.

Reviewed by: Wcarchive and David Greenman

John Aycock's BSD copyrighted sequencer assembler and sequencer code. This
is identical to the older version, just the copyright has changed. Many
thanks go to Dean Gehnert of the Linux camp who went the extra mile to make
this happen.

Other changes:

Update assembler man page to include the -v and -D options

Merge in Dean's latest changes to the assembler

Have the sequencer do a MSG_REJECT when the negotiated syncronous rate
is lower than the adapter supports. This forces asyncronous mode which
is faster at these rates anyway.

This code will be moved shortly to the non-gpld portion of the tree.

More code optimizations. Use a slightly different approach to decide
whether a reconnecting target is a tagged device or not.

Off by one error in -MSG-START+0 was just Justin being tired -- revert to
old value.

Remove unnecessary check for active messages in setup SCB. This same test
would also jump to p_mesgin_done which would "ACK" an extra time possibly
confusing the target.

Tell the kernel driver whenever we send an ABORT_TAG message.

Major overhaul of the aic7xxx driver:
- Report valid residual byte counts. We actually pause the sequencer
when the residual is non-zero. I thought about using DMA to do this,
bus sequencer program space is tight.

- Fix embarassing off by one error in the computation of a 2's
compliment variable. This was most likely the cause of the
many problems reported with the tagged queuing code.

- Handle "MAX_SYNC" as a special case (ie we are the ones starting
the sync negotiation sequence). This was done so that the target
scratch area can be initialed to 0 offset (asyncronous transfers)
safely. The initialization to 0 (was 15) is necessary since in
some cases a Wide negotiation could run into problems if SCSIRATE
was set wrong and we went into data(in/out).

- Trim the DMA routines a little by using some procedures. Net
effect is more functionality with 3 less instructions after this
update.

- Toggle the WIDEODD bit of the DFCNTRL whenever this is not the
last SG block. It has no effect in the 8bit bus configuration,
but in the Wide configuration ensures that the overlap byte is
held in the SCSI block if the transfer is odd so it will end
up in the next SG (the correct behavior).

Make the aic7xxx assembler take quoted strings as a single token.
Make $Id the version variable which required the quoted string "feature".

Be careful to maintain the bits in SBLKCTL that are reserved.

Add tagged queueing support to the aic7xxx sequencer code.

Have version number track CSV version number. No other change.

aic7xxx.c:
Print out the length of the compiled sequencer program.

aic7xxx.seq:
More optimizations. Replace generic bcopy routine with bcopy_3
and bcopy_4 (ie unroll the loops) since these are the only two cases used.
Initialize SIMODE1 and SXFRCTL1 from the kernel in ahc_init instead of
at each selection/reselection since this is expensive and only needs to
be done once. Condense function returns into previous instruction if possible.
Reorder some sections to kill superflous jumps. These optimizations kill
the ~150k/s penalty adding support for Twin/Wide cards was costing since
the last place in the commaon path of execution where we had to do ugly,
convoluted testing for the type of card in the sequencer has gone away.
Next stop tagged queuing and target mode.

At $Ids to all files. Have the sequencer use DMA to tranfer its SCB
(SCSI control block) instead of having the host PIO it down. Also
reimplement WDTR and SDTR optimization to remove code in the sequencer
and place the responsibility of knowing when to initiate SDTR or WDTR
on the kernel driver. This vastly shortens the sequencer program yet
yeilds the same performance.

Full support for 294x and Wide devices. Fixed month old bug in the SCSI
sense retrieval code that messed up CDROM devices. This code will also
responde correctly to SDTR and WDTR messages from devices that start a
negotiation sequence.

Update the sequencer code to handle both channels of Twin channel devices.
You can now sling 14 devices off of a 274xT. In the process of adding
twin channel support, I removed all evident restrictions on supporting
Wide channeled devices, but I do not have a Wide controller to test them
on.

aic7770_seq.h, the pre-compiled header, is no longer needed since config
handles this dependancy.

Merge in latest Linux sequencer code release with my changes. This should
make the sequencer code fully compatible with the aic7870 (ie 294x adaptors).
I've also added to my local mods putting the sequencer into "FASTMODE" clock.
This gives upwards of 2M/sec write preformance improvement in some scenarios.
There haven't been any reports of this causing problems, and I have been
reaping the benifits of it for more than a week now.

This also includes a new version of the pre-generated file <ugh>

Obtained from: John Aycock (aycock@cpsc.ucalgary.ca) and myself

John Aycock's aic7770 sequencer code and assembler. There is currently
a discussion going on about removing this code from the burden of the
GPL, but it won't happen before Beta, and this code should be tested
before release.

Supports 27/2842 class adaptec cards and is almost capable of supporting
aic7870 based adapters (294X series cards). It does not support Wide
controllers or the second channel on Twin boards although I have work in
progress on getting both channels and running.

I have also added a few performance improvements to this version that give
us approximately a 25% boost over the original driver. These patches have
been submitted to the author.

Obtained from: Linux aic7770 driver (John Aycock - aycock@cpsc.ucalgary.ca)