History log of /freebsd-11-stable/sys/dev/mii/mii_physubr.c
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# 331722 29-Mar-2018 eadler

Revert r330897:

This was intended to be a non-functional change. It wasn't. The commit
message was thus wrong. In addition it broke arm, and merged crypto
related code.

Revert with prejudice.

This revert skips files touched in r316370 since that commit was since
MFCed. This revert also skips files that require $FreeBSD$ property
changes.

Thank you to those who helped me get out of this mess including but not
limited to gonzo, kevans, rgrimes.

Requested by: gjb (re)


# 330897 14-Mar-2018 eadler

Partial merge of the SPDX changes

These changes are incomplete but are making it difficult
to determine what other changes can/should be merged.

No objections from: pfg


# 302408 07-Jul-2016 gjb

Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

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


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# 297793 10-Apr-2016 pfg

Cleanup unnecessary semicolons from the kernel.

Found with devel/coccinelle.


# 281821 21-Apr-2015 glebius

Instead of storing mii_media_table array index in ifm_data, determine
it in mii_phy_setmedia() functionally.

Sponsored by: Nginx, Inc.


# 277176 14-Jan-2015 glebius

Clean some dead code.


# 257184 26-Oct-2013 glebius

The MII layer shouldn't care about administrative status of an
interface. Make MII drivers forget about 'struct ifnet'.

Later plan is to provide an administrative downcall from ifnet
layer into drivers, to inform them about administrative status
change. If someone thinks that processing MII events for an
administratively down interface is a big problem, then drivers
would turn MII processing off.

The following MII drivers do evil things, like strcmp() on
driver name, so they still need knowledge of ifnet and thus
include if_var.h. They all need to be fixed:

sys/dev/mii/brgphy.c
sys/dev/mii/e1000phy.c
sys/dev/mii/ip1000phy.c
sys/dev/mii/jmphy.c
sys/dev/mii/nsphy.c
sys/dev/mii/rgephy.c
sys/dev/mii/truephy.c

Sponsored by: Netflix
Sponsored by: Nginx, Inc.


# 225014 19-Aug-2011 marius

r221812 reveals that at least some Broadcom PHYs default to being not only
isolated but also powered down after a reset and while they just work fine
[sic] when both is the case they don't if they are only deisolate but still
powered down. So in order to put PHYs in an overall normal operation mode
for the common case, ensure in mii_phy_reset() that they are not powered
down after a reset. Unfortunately, this only helps in case of BCM5421,
while BCM5709S apparently only work when they remain isolated and powered
down after a reset. So don't call mii_phy_reset() in brgphy_reset() and
implement the reset locally leaving the problematic bits alone. Effectively
this bypasses r221812 for brgphy(4).
Thanks to Justin Hibbits for doing a binary search in order to identify
the problematic commit.

PR: 157405, 158156
Reviewed by: yongari (mii_phy_reset() part)
Approved by: re (kib)
MFC after: 3 days


# 221812 12-May-2011 marius

Some PHYs like the Level One LXT970 optionally can default to isolation
after rest, in which case we may need to deisolate it.
Tested by: nwhitehorn

MFC after 1 week


# 221407 03-May-2011 marius

- Remove attempts to implement setting of BMCR_LOOP/MIIF_NOLOOP
(reporting IFM_LOOP based on BMCR_LOOP is left in place though as
it might provide useful for debugging). For most mii(4) drivers it
was unclear whether the PHYs driven by them actually support
loopback or not. Moreover, typically loopback mode also needs to
be activated on the MAC, which none of the Ethernet drivers using
mii(4) implements. Given that loopback media has no real use (and
obviously hardly had a chance to actually work) besides for driver
development (which just loopback mode should be sufficient for
though, i.e one doesn't necessary need support for loopback media)
support for it is just dropped as both NetBSD and OpenBSD already
did quite some time ago.
- Let mii_phy_add_media() also announce the support of IFM_NONE.
- Restructure the PHY entry points to use a structure of entry points
instead of discrete function pointers, and extend this to include
a "reset" entry point. Make sure any PHY-specific reset routine is
always used, and provide one for lxtphy(4) which disables MII
interrupts (as is done for a few other PHYs we have drivers for).
This includes changing NIC drivers which previously just called the
generic mii_phy_reset() to now actually call the PHY-specific reset
routine, which might be crucial in some cases. While at it, the
redundant checks in these NIC drivers for mii->mii_instance not being
zero before calling the reset routines were removed because as soon
as one PHY driver attaches mii->mii_instance is incremented and we
hardly can end up in their media change callbacks etc if no PHY driver
has attached as mii_attach() would have failed in that case and not
attach a miibus(4) instance.
Consequently, NIC drivers now no longer should call mii_phy_reset()
directly, so it was removed from EXPORT_SYMS.
- Add a mii_phy_dev_attach() as a companion helper to mii_phy_dev_probe().
The purpose of that function is to perform the common steps to attach
a PHY driver instance and to hook it up to the miibus(4) instance and to
optionally also handle the probing, addition and initialization of the
supported media. So all a PHY driver without any special requirements
has to do in its bus attach method is to call mii_phy_dev_attach()
along with PHY-specific MIIF_* flags, a pointer to its PHY functions
and the add_media set to one. All PHY drivers were updated to take
advantage of mii_phy_dev_attach() as appropriate. Along with these
changes the capability mask was added to the mii_softc structure so
PHY drivers taking advantage of mii_phy_dev_attach() but still
handling media on their own do not need to fiddle with the MII attach
arguments anyway.
- Keep track of the PHY offset in the mii_softc structure. This is done
for compatibility with NetBSD/OpenBSD.
- Keep track of the PHY's OUI, model and revision in the mii_softc
structure. Several PHY drivers require this information also after
attaching and previously had to wrap their own softc around mii_softc.
NetBSD/OpenBSD also keep track of the model and revision on their
mii_softc structure. All PHY drivers were updated to take advantage
as appropriate.
- Convert the mebers of the MII data structure to unsigned where
appropriate. This is partly inspired by NetBSD/OpenBSD.
- According to IEEE 802.3-2002 the bits actually have to be reversed
when mapping an OUI to the MII ID registers. All PHY drivers and
miidevs where changed as necessary. Actually this now again allows to
largely share miidevs with NetBSD, which fixed this problem already
9 years ago. Consequently miidevs was synced as far as possible.
- Add MIIF_NOMANPAUSE and mii_phy_flowstatus() calls to drivers that
weren't explicitly converted to support flow control before. It's
unclear whether flow control actually works with these but typically
it should and their net behavior should be more correct with these
changes in place than without if the MAC driver sets MIIF_DOPAUSE.

Obtained from: NetBSD (partially)
Reviewed by: yongari (earlier version), silence on arch@ and net@


# 220938 22-Apr-2011 marius

Correct spelling in comments.

Submitted by: brucec


# 217414 14-Jan-2011 marius

- Don't announce PAUSE support for half-duplex when MIIF_FORCEPAUSE is
set.
- Let mii_phy_auto() also announce PAUSE support for 10baseT-FDX.

MFC after: 1 week


# 215297 14-Nov-2010 marius

o Flesh out the generic IEEE 802.3 annex 31B full duplex flow control
support in mii(4):
- Merge generic flow control advertisement (which can be enabled by
passing by MIIF_DOPAUSE to mii_attach(9)) and parsing support from
NetBSD into mii_physubr.c and ukphy_subr.c. Unlike as in NetBSD,
IFM_FLOW isn't implemented as a global option via the "don't care
mask" but instead as a media specific option this. This has the
following advantages:
o allows flow control advertisement with autonegotiation to be
turned on and off via ifconfig(8) with the default typically
being off (though MIIF_FORCEPAUSE has been added causing flow
control to be always advertised, allowing to easily MFC this
changes for drivers that previously used home-grown support for
flow control that behaved that way without breaking POLA)
o allows to deal with PHY drivers where flow control advertisement
with manual selection doesn't work or at least isn't implemented,
like it's the case with brgphy(4), e1000phy(4) and ip1000phy(4),
by setting MIIF_NOMANPAUSE
o the available combinations of media options are readily available
from the `ifconfig -m` output
- Add IFM_FLOW to IFM_SHARED_OPTION_DESCRIPTIONS and IFM_ETH_RXPAUSE
and IFM_ETH_TXPAUSE to IFM_SUBTYPE_ETHERNET_OPTION_DESCRIPTIONS so
these are understood by ifconfig(8).
o Make the master/slave support in mii(4) actually usable:
- Change IFM_ETH_MASTER from being implemented as a global option via
the "don't care mask" to a media specific one as it actually is only
applicable to IFM_1000_T to date.
- Let mii_phy_setmedia() set GTCR_MAN_MS in IFM_1000_T slave mode to
actually configure manually selected slave mode (like we also do in
the PHY specific implementations).
- Add IFM_ETH_MASTER to IFM_SUBTYPE_ETHERNET_OPTION_DESCRIPTIONS so it
is understood by ifconfig(8).
o Switch bge(4), bce(4), msk(4), nfe(4) and stge(4) along with brgphy(4),
e1000phy(4) and ip1000phy(4) to use the generic flow control support
instead of home-grown solutions via IFM_FLAGs. This includes changing
these PHY drivers and smcphy(4) to no longer unconditionally advertise
support for flow control but only if the selected media has IFM_FLOW
set (or MIIF_FORCEPAUSE is set) and implemented for these media variants,
i.e. typically only for copper.
o Switch brgphy(4), ciphy(4), e1000phy(4) and ip1000phy(4) to report and
set IFM_1000_T master mode via IFM_ETH_MASTER instead of via IFF_LINK0
and some IFM_FLAGn.
o Switch brgphy(4) to add at least the the supported copper media based on
the contents of the BMSR via mii_phy_add_media() instead of hardcoding
them. The latter approach seems to have developed historically, besides
causing unnecessary code duplication it was also undesirable because
brgphy_mii_phy_auto() already based the capability advertisement on the
contents of the BMSR though.
o Let brgphy(4) set IFM_1000_T master mode on all supported PHY and not
just BCM5701. Apparently this was a misinterpretation of a workaround
in the Linux tg3 driver; BCM5701 seem to require RGPHY_1000CTL_MSE and
BRGPHY_1000CTL_MSC to be set when configuring autonegotiation but
this doesn't mean we can't set these as well on other PHYs for manual
media selection.
o Let ukphy_status() report IFM_1000_T master mode via IFM_ETH_MASTER so
IFM_1000_T master mode support now is generally available with all PHY
drivers.
o Don't let e1000phy(4) set master/slave bits for IFM_1000_SX as it's
not applicable there.

Reviewed by: yongari (plus additional testing)
Obtained from: NetBSD (partially), OpenBSD (partially)
MFC after: 2 weeks


# 214608 31-Oct-2010 marius

Turn a panic into a printf so IFM_ETH_MASTER on !IFM_1000_T is complained
about but otherwise ignored. When allowing the master to be set manually via
ifconfig(8) by adding the former to IFM_SUBTYPE_ETHERNET_OPTION_DESCRIPTIONS
(as it should be) it seems to be unfavorable that a machine can be made to
panic with a simple ifconfig(8) invocation.


# 214606 31-Oct-2010 marius

Try to make the style consistent (including regarding NetBSD bits not yet
merged) and adhere style(9).


# 214265 24-Oct-2010 marius

- Given that as of r214264 all PHY drivers using mii(4) finally have been
converted to use the mii_phy_add_media()/mii_phy_setmedia() pair instead
of mii_add_media()/mii_anar() remove the latter.
- Declare mii_media mii_media_table static as it shouldn't be used outside
of mii_physubr.c.

MFC after: never


# 213229 27-Sep-2010 marius

Use the mii_data provided via mii_attach_args and mii_pdata respectively
instead of reaching out for the softc of the parent.


# 204646 03-Mar-2010 joel

The NetBSD Foundation has granted permission to remove clause 3 and 4 from
the software.

Obtained from: NetBSD


# 165990 12-Jan-2007 marius

Remove mii_media_from_bmcr(); all previous users have been converted to
use mii_phy_add_media()/mii_phy_setmedia().


# 164827 02-Dec-2006 marius

Add a helper function mii_phy_dev_probe(), which wraps around the
mii_phy_match() API and takes care of the PHY device probe based on
the struct mii_phydesc array and the match return value provided.
Convert PHY drivers to take advantage of mii_phy_dev_probe(),
converting drivers to provide a mii_phydesc table in the first
place where necessary.

Reviewed by: yongari
MFC after: 2 weeks


# 164703 27-Nov-2006 marius

Analogous to mii_add_media(), factor out the code for checking whether
the BMSR contains any media at all to mii_phy_add_media(). The majority
of the drivers currently using mii_phy_add_media() were missing such a
check anyway though.

MFC after: 2 weeks


# 164702 27-Nov-2006 marius

- Add a MIIF_FORCEANEG flag which forces an auto-negotiation to always
take place if IFM_AUTO is selected. This allows drivers like nsphy(4),
which need to force writing the ANAR according to the BMSR, to take
advantage of mii_phy_setmedia(). [1]
- In mii_phy_reset() once the current media is set don't isolate the PHY
corresponding to the instance of the currently selected media rather
than unconditionally not isolating the PHY corresponding to instance 0.
This saves a isolation-unisolation-cycle of the PHY corresponding to
the currently selected media for the case were it isn't instance 0.
- Fix some whitespace nits. [1]

Obtained from: NetBSD [1]
MFC after: 2 weeks


# 160082 03-Jul-2006 oleg

Reset autonegotiation timer if current media is not 'auto'.

Approved by: glebius (mentor)
MFC after: 2 weeks


# 158649 16-May-2006 oleg

1) Fix mii_phy_tick():
Current code does not report link loss correctly - when link goes down,
mii_phy_tick() will notice that with up to mii_anegticks delay.
If link goes up during this delay then link flapping will be unnoticed
by driver.

2) mii_phy_add_media(): initialize sc->mii_anegticks for 10/100 media

3) Use MII_ANEGTICKS/MII_ANEGTICKS_GIGE defines instead of hardcoded values.

Approved by: glebius (mentor)
MFC after: 1 month


# 150756 30-Sep-2005 imp

Add a more generic version of the mii_phy_match routine (mii_phy_match_gen)
which can be used for phy that want to piggy back other data with their
table.


# 141937 15-Feb-2005 imp

Use ANSI function definitions, in preference to the K&R definitions.


# 129844 29-May-2004 marius

Remove double __FBSDID and move the remaining one into a common place after
the license(s) and before the driver comment (the latter only in drivers not
having __FBSDID at that location).


# 128870 03-May-2004 andre

Correct the phy_service() routine case MII_TICK to correctly track
the falling edge of a media state change.

This is in preparation for media state change notification to the
routing socket.

No objections by: sam, wpaul, ru, bms
Brucification by: bde


# 119418 24-Aug-2003 obrien

Use __FBSDID().
Also some minor style cleanups.


# 115520 31-May-2003 phk

Remove unnecessary breaks.
Remove unused variables.
Add XXX comment where a break may be missing. [lxtphy.c]

Found by: FlexeLint


# 113038 03-Apr-2003 obrien

Use __FBSDID rather than rcsid[].


# 96027 04-May-2002 phk

Increase gigE negotiation timeout to 17 seconds.

10 seconds is not enough to negotiate a gigE link with a cisco switch which
holds carrier off for several seconds between tries.


# 96026 04-May-2002 phk

Clean up mii/phy drivers: Remove the MIIF_DOINGAUTO which doesn't really
do anything at the end of the day except bloat the drivers which has
copy&pasted it.


# 95724 29-Apr-2002 phk

Introduce NetBSD's mii_phy_match() API and use it in the nsgphy to
get a description printed.


# 95722 29-Apr-2002 phk

Make one generic mii_phy_detach() to replace 19 slightly different ones.

Rename mii_phy_auto_stop() mii_phy_down().

Introduce mii_down(), use it from nge. Do not indirect it to 19 identical
case's in 19 switchstatements like NetBSD did.


# 95718 29-Apr-2002 phk

Move a lot closer to NetBSDs MII support for GigE.

Move fxp and nge drivers over to use the new stuff.


# 95707 29-Apr-2002 phk

Moving closer to being able to use NetBSD's generic mii_set_media()
function.


# 95705 29-Apr-2002 phk

Edging ever closer to NetBSD...


# 95667 28-Apr-2002 phk

Don't pass three args when one will do just fine, and even prevent
mistakes like the one brgphy.c (now corrected).


# 95665 28-Apr-2002 phk

Improve an API by about 4 lines per driver.


# 92739 20-Mar-2002 alfred

Remove __P.


# 84141 29-Sep-2001 jlemon

Forced commit: common service routines mii_phy_update() and mii_phy_tick()
have also been added, and can be used to factor out common code from the
various mii drivers.


# 84140 29-Sep-2001 jlemon

Add new device method miibus_linkchg, along with a service routine.


# 69925 12-Dec-2000 wpaul

Grrrrr. That last commit was supposed to be to the head, not to -stable
(even though I want the fixes in -stable anyway). I'm sure I'm going
to get flamed now for committing to -stable and -current too quickly.
*sigh*


# 67164 15-Oct-2000 phk

Remove unneeded #include <machine/clock.h>


# 50477 27-Aug-1999 peter

$Id$ -> $FreeBSD$


# 50120 21-Aug-1999 wpaul

This commit adds support for the NetBSD MII abstraction layer and
MII-compliant PHY drivers. Many 10/100 ethernet NICs available today
either use an MII transceiver or have built-in transceivers that can
be programmed using an MII interface. It makes sense then to separate
this support out into common code instead of duplicating it in all
of the NIC drivers. The mii code also handles all of the media
detection, selection and reporting via the ifmedia interface.

This is basically the same code from NetBSD's /sys/dev/mii, except
it's been adapted to FreeBSD's bus architecture. The advantage to this
is that it automatically allows everything to be turned into a
loadable module. There are some common functions for use in drivers
once an miibus has been attached (mii_mediachg(), mii_pollstat(),
mii_tick()) as well as individual PHY drivers. There is also a
generic driver for all PHYs that aren't handled by a specific driver.
It's possible to do this because all 10/100 PHYs implement the same
general register set in addition to their vendor-specific register
sets, so for the most part you can use one driver for pretty much
any PHY. There are a couple of oddball exceptions though, hence
the need to have specific drivers.

There are two layers: the generic "miibus" layer and the PHY driver
layer. The drivers are child devices of "miibus" and the "miibus" is
a child of a given NIC driver. The "miibus" code and the PHY drivers
can actually be compiled and kldoaded as completely separate modules
or compiled together into one module. For the moment I'm using the
latter approach since the code is relatively small.

Currently there are only three PHY drivers here: the generic driver,
the built-in 3Com XL driver and the NS DP83840 driver. I'll be adding
others later as I convert various NIC drivers to use this code.

I realize that I'm cvs adding this stuff instead of importing it
onto a separate vendor branch, but in my opinion the import approach
doesn't really offer any significant advantage: I'm going to be
maintaining this stuff and writing my own PHY drivers one way or
the other.