MIPS: fix typos in comments

Various spelling mistakes in comments.
Detected with the help of Coccinelle.

Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

mips: DEC: honor CONFIG_MIPS_FP_SUPPORT=n

Include the DECstation interrupt handler in opting out of
FPU support.

Fixes a linker error:

mips-linux-ld: arch/mips/dec/int-handler.o: in function `fpu':
(.text+0x148): undefined reference to `handle_fpe_int'

Fixes: 183b40f992c8 ("MIPS: Allow FP support to be disabled")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: kernel test robot <lkp@intel.com>
Cc: Paul Burton <paulburton@kernel.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Maciej W. Rozycki <macro@orcam.me.uk>
Cc: linux-mips@vger.kernel.org
Acked-by: Maciej W. Rozycki <macro@orcam.me.uk>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: Allow modules to set board_be_handler

After making the brcmstb_gisb driver modular with 707a4cdf86e5 ("bus:
brcmstb_gisb: Allow building as module") Guenter reported that mips
allmodconfig failed to link because board_be_handler was referenced.

Thomas indicated that if we were to continue making the brcmstb_gisb
driver modular for MIPS we would need to introduce a function that
allows setting the board_be_handler and export that function towards
modules.

This is what is being done here: board_be_handler is made static and is
now settable with a mips_set_be_handler() function which is exported.

Reported-by: Guenter Roeck <linux@roeck-us.net>
Suggested-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Fixes: 707a4cdf86e5 ("bus: brcmstb_gisb: Allow building as module")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: DEC: Restore bootmem reservation for firmware working memory area

Fix a crash on DEC platforms starting with:

VFS: Mounted root (nfs filesystem) on device 0:11.
Freeing unused PROM memory: 124k freed
BUG: Bad page state in process swapper pfn:00001
page:(ptrval) refcount:0 mapcount:-128 mapping:00000000 index:0x1 pfn:0x1
flags: 0x0()
raw: 00000000 00000100 00000122 00000000 00000001 00000000 ffffff7f 00000000
page dumped because: nonzero mapcount
Modules linked in:
CPU: 0 PID: 1 Comm: swapper Not tainted 5.9.0-00858-g865c50e1d279 #1
Stack : 8065dc48 0000000b 8065d2b8 9bc27dcc 80645bfc 9bc259a4 806a1b97 80703124
80710000 8064a900 00000001 80099574 806b116c 1000ec00 9bc27d88 806a6f30
00000000 00000000 80645bfc 00000000 31232039 80706ba4 2e392e35 8039f348
2d383538 00000070 0000000a 35363867 00000000 806c2830 80710000 806b0000
80710000 8064a900 00000001 81000000 00000000 00000000 8035af2c 80700000
...
Call Trace:
[<8004bc5c>] show_stack+0x34/0x104
[<8015675c>] bad_page+0xfc/0x128
[<80157714>] free_pcppages_bulk+0x1f4/0x5dc
[<801591cc>] free_unref_page+0xc0/0x130
[<8015cb04>] free_reserved_area+0x144/0x1d8
[<805abd78>] kernel_init+0x20/0x100
[<80046070>] ret_from_kernel_thread+0x14/0x1c
Disabling lock debugging due to kernel taint

caused by an attempt to free bootmem space that as from
commit b93ddc4f9156 ("mips: Reserve memory for the kernel image resources")
has not been anymore reserved due to the removal of generic MIPS arch code
that used to reserve all the memory from the beginning of RAM up to the
kernel load address.

This memory does need to be reserved on DEC platforms however as it is
used by REX firmware as working area, as per the TURBOchannel firmware
specification[1]:

Table 2-2 REX Memory Regions
-------------------------------------------------------------------------
Starting Ending
Region Address Address Use
-------------------------------------------------------------------------
0 0xa0000000 0xa000ffff Restart block, exception vectors,
REX stack and bss
1 0xa0010000 0xa0017fff Keyboard or tty drivers

2 0xa0018000 0xa001f3ff 1) CRT driver

3 0xa0020000 0xa002ffff boot, cnfg, init and t objects

4 0xa0020000 0xa002ffff 64KB scratch space
-------------------------------------------------------------------------
1) Note that the last 3 Kbytes of region 2 are reserved for backward
compatibility with previous system software.
-------------------------------------------------------------------------

(this table uses KSEG2 unmapped virtual addresses, which in the MIPS
architecture are offset from physical addresses by a fixed value of
0xa0000000 and therefore the regions referred do correspond to the
beginning of the physical address space) and we call into the firmware
on several occasions throughout the bootstrap process. It is believed
that pre-REX firmware used with non-TURBOchannel DEC platforms has the
same requirements, as hinted by note #1 cited.

Recreate the discarded reservation then, in DEC platform code, removing
the crash.

References:

[1] "TURBOchannel Firmware Specification", On-line version,
EK-TCAAD-FS-004, Digital Equipment Corporation, January 1993,
Chapter 2 "System Module Firmware", p. 2-5

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Fixes: b93ddc4f9156 ("mips: Reserve memory for the kernel image resources")
Cc: stable@vger.kernel.org # v5.2+

Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: pass non-NULL dev_id on shared request_irq()

Recently all usages of setup_irq() was replaced by request_irq().
request_irq() does a few sanity checks that were not done in
setup_irq(), if they fail irq registration will fail. One of the check
is to ensure that non-NULL dev_id is passed in the case of shared irq.
This caused malta on qemu to hang.

Fix it by passing handler as dev_id to all request_irq()'s that are
shared. For sni, instead of passing non-NULL dev_id, remove shared irq
flags.

Fixes: ac8fd122e070 ("MIPS: Replace setup_irq() by request_irq()")
Reported-by: Nathan Chancellor <natechancellor@gmail.com>
Suggested-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: afzal mohammed <afzal.mohd.ma@gmail.com>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: Replace setup_irq() by request_irq()

request_irq() is preferred over setup_irq(). Invocations of setup_irq()
occur after memory allocators are ready.

Per tglx[1], setup_irq() existed in olden days when allocators were not
ready by the time early interrupts were initialized.

Hence replace setup_irq() by request_irq().

remove_irq() has been replaced by free_irq() as well.

There were build error's during previous version, couple of which was
reported by kbuild test robot <lkp@intel.com> of which one was reported
by Thomas Bogendoerfer <tsbogend@alpha.franken.de> as well. There were a
few more issues including build errors, those also have been fixed.

[1] https://lkml.kernel.org/r/alpine.DEB.2.20.1710191609480.1971@nanos

Signed-off-by: afzal mohammed <afzal.mohd.ma@gmail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: Audit and remove any unnecessary uses of module.h

Historically a lot of these existed because we did not have
a distinction between what was modular code and what was providing
support to modules via EXPORT_SYMBOL and friends. That changed
when we forked out support for the latter into the export.h file.

This means we should be able to reduce the usage of module.h
in code that is obj-y Makefile or bool Kconfig. In the case of
some code where it is modular, we can extend that to also include
files that are building basic support functionality but not related
to loading or registering the final module; such files also have
no need whatsoever for module.h

The advantage in removing such instances is that module.h itself
sources about 15 other headers; adding significantly to what we feed
cpp, and it can obscure what headers we are effectively using.

Since module.h might have been the implicit source for init.h
(for __init) and for export.h (for EXPORT_SYMBOL) we consider each
instance for the presence of either and replace/add as needed.

Also note that MODULE_DEVICE_TABLE is a no-op for non-modular code.

Build coverage of all the mips defconfigs revealed the module.h
header was masking a couple of implicit include instances, so
we add the appropriate headers there.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: David Daney <david.daney@cavium.com>
Cc: John Crispin <john@phrozen.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: "Steven J. Hill" <steven.hill@cavium.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/15131/
[james.hogan@imgtec.com: Preserve sort order where it already exists]
Signed-off-by: James Hogan <james.hogan@imgtec.com>

MIPS: DEC: Export `ioasic_ssr_lock' to modules

Fix a modular `declance' regression caused by LMO commit bb46bf30d13f
("DECstation SCSI driver clean-ups.")

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/13256/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: DEC: Do not set up the FPU interrupt if no FPU

Following the arrangement for processors that wire FPU exceptions to the
FPE CPU exception handle the case where no FPU is in use -- which for
DECstation systems will only ever happen when the "nofpu" kernel option
has been used -- do not register the FPU interrupt in such a case
either.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9714/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: DEC: Implement FPU interrupt counter

Implement a cheap way to count FPU interrupts for R2k/R3k DECstation
systems. Do this manually in handcoded assembly, rather than calling
`kstat_incr_irq_this_cpu' that would require setting up a stack frame
and a lot of redirection. This is not going to be a problem because the
FPU interrupt is local to the CPU and also there is one CPU only anyway.

So at bootstrap determine the address of the correct location within
`struct irq_desc', and then only refer to it directly in the interrupt
handler.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9713/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: DEC: Remove the Halt button interrupt on R4k systems

On R4k DECstations the Halt button is wired to the NMI processor input
rather than an ordinary interrupt input such as on R3k DECstations. This
is possible with a different design of the CPU daughtercard that routes
the Halt button line from the baseboard connector. Additionally the
interrupt input has been reused for a different purpose on the KN04 and
KN05 R4k CPU daughtercards so it is better kept masked.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/6705/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

DEC: Whitespace cleanup

Commit 7034228792cc561e79ff8600f02884bd4c80e287 [MIPS: Whitespace
cleanup.] did a lot of good and a little damage. Revert the damage.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5875/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: Whitespace cleanup.

Having received another series of whitespace patches I decided to do this
once and for all rather than dealing with this kind of patches trickling
in forever.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: irq: Remove IRQF_DISABLED

Since commit [e58aa3d2: genirq: Run irq handlers with interrupts disabled],
We run all interrupt handlers with interrupts disabled and we even check
and yell when an interrupt handler returns with interrupts enabled (see
commit [b738a50a: genirq: Warn when handler enables interrupts]).

So now this flag is a NOOP and can be removed.

[ralf@linux-mips.org: Fixed up conflicts in
arch/mips/alchemy/common/dbdma.c, arch/mips/cavium-octeon/smp.c and
arch/mips/kernel/perf_event.c.]

Signed-off-by: Yong Zhang <yong.zhang0@gmail.com>
To: linux-kernel@vger.kernel.org
Cc: tglx@linutronix.de
linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2835/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: Mark cascade and low level interrupts IRQF_NO_THREAD

Mark interrupts with no_action handler, cascade interrupts, low level
interrupts (bus error, halt ..) with IRQF_NO_THREAD to exclude them
from forced threading.

Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mips@linux-mips.org
Cc: Wu Zhangjin <wuzhangjin@gmail.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: Add missing #inclusions of <linux/irq.h>

Add missing #inclusions of <linux/irq.h> to a whole bunch of files that should
really include it. Note that this can replace #inclusions of <asm/irq.h>.

This is required for the patch to sort out irqflags handling function naming to
compile on MIPS.

The problem is that these files require access to things like setup_irq() -
which isn't available by #including <linux/interrupt.h>

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>

[MIPS] Deforest the function pointer jungle in the time code.

Hard to follow who is pointing what to where and why so it's simply getting
in the way of the time code renovation.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

[MIPS] DEC: Initialise ioasic_ssr_lock

Fix the definition of the ioasic_ssr_lock spinlock to include a proper
initialisation.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

[TC] TURBOchannel support for the DECstation

This is the platform-specific part of TURBOchannel bus support for the
DECstation. It implements determining whether the bus is actually there,
getting bus parameters, IRQ assignments for devices and protected accesses
to possibly unoccupied slots that may trigger bus error exceptions.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

[MIPS] Define MIPS_CPU_IRQ_BASE in generic header

The irq_base for {mips,rm7k,rm9k}_cpu_irq_init() are constant on all
platforms and are same value on most platforms (0 or 16, depends on
CONFIG_I8259). Define them in asm-mips/mach-generic/irq.h and make
them customizable. This will save a few cycle on each CPU interrupt.

A good side effect is removing some dependencies to MALTA in generic
SMTC code.

Although MIPS_CPU_IRQ_BASE is customizable, this patch changes irq
mappings on DDB5477, EMMA2RH and MIPS_SIM, since really customizing
them might cause some header dependency problem and there seems no
good reason to customize it. So currently only VR41XX is using custom
MIPS_CPU_IRQ_BASE value, which is 0 regardless of CONFIG_I8259.

Testing this patch on those platforms is greatly appreciated. Thank
you.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

[MIPS] do_IRQ cleanup

Now we have both function and macro version of do_IRQ() and the former
is used only by DEC and non-preemptive kernel. This patch makes
everyone use the macro version and removes the function version.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

[MIPS] DEC: pt_regs fixes for dec_intr_halt.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

[MIPS] Replace board_timer_setup function pointer by plat_timer_setup.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

---

[PATCH] irq-flags: MIPS: Use the new IRQF_ constants

Use the new IRQF_ constants and remove the SA_INTERRUPT define

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[MIPS] Cleanup memory managment initialization.

Historically plat_mem_setup did the entire platform initialization. This
was rather impractical because it meant plat_mem_setup had to get away
without any kind of memory allocator. To keep old code from breaking
plat_setup was just renamed to plat_setup and a second platform
initialization hook for anything else was introduced.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

[MIPS] Rewrite all the assembler interrupt handlers to C.

Saves like 1,600 lines of code, is way easier to debug, compilers
frequently do a better job than the cut and paste type of handlers many
boards had. And finally having all the stuff done in a single place
also means alot of bug potencial for the MT ASE is gone.

The only surviving handler in assembler is the DECstation one; I hope
Maciej will rewrite it.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

[MIPS] Rename _machine_power_off to pm_power_off so the kernel builds again.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

Make static what ought to be static.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

Use physical addresses at the interface level, letting drivers remap
them as appropriate.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

System-specific handling of bus errors for DECstation variations
supporting parity errors only for memory (Pmax/3min/Maxine).
Fixes for resources decoded by the KN04/KN05 MB ASIC. Additional
clean-ups for the ECC handler.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

There is NO port I/O space on the DECstation. Minor clean-ups.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

Get rid of early_init. There's more need to make this form of
initialization actually useful and as is certainly unmergable with
upstream.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!