Commit graph

520 commits

Author SHA1 Message Date
Matthew Wilcox
e62438630c [PATCH] Centralise definitions of sector_t and blkcnt_t
CONFIG_LBD and CONFIG_LSF are spread into asm/types.h for no particularly
good reason.

Centralising the definition in linux/types.h means that arch maintainers
don't need to bother adding it, as well as fixing the problem with
x86-64 users being asked to make a decision that has absolutely no
effect.

The H8/300 porters seem particularly confused since I'm not aware of any
microcontrollers that need to support 2TB filesystems.

Signed-off-by: Matthew Wilcox <matthew@wil.cx>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-04 19:41:15 -08:00
Ralf Baechle
0004a9dfea [MIPS] Cleanup memory barriers for weakly ordered systems.
Also the R4000 / R4600 LL/SC instructions imply a sync so no explicit sync
needed.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-12-04 22:43:14 +00:00
Ralf Baechle
4f8b5c7096 [MIPS] Fix atomic.h build errors.
For the definition of atomic64_t atomic.h was relying on <asm/types.h>
having been included previously.  Before changeset
d89d8e0637a5e4e0a12e90c4bc934d0d4c335239 this was happening as a
side effect of including <linux/spinlock.h>.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-12-04 22:43:13 +00:00
Atsushi Nemoto
05e4396651 [MIPS] Use SYSVIPC_COMPAT to fix various problems on N32
N32 SysV IPC system calls should use 32-bit compatible code.
arch/mips/kernel/linux32.c have similar compatible code for O32, but
ipc/compat.c seems more complete.  We can use it for both N32 and O32.

This patch should fix these problems (and other possible problems):

http://www.linux-mips.org/cgi-bin/mesg.cgi?a=linux-mips&i=1149188824.6986.6.camel%40diimka-laptop
http://www.linux-mips.org/cgi-bin/mesg.cgi?a=linux-mips&i=44C6B829.8050508%40caviumnetworks.com

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-12-04 22:43:12 +00:00
Mariusz Kozlowski
9567772f14 [MIPS] klconfig add missing bracket
Signed-off-by: Mariusz Kozlowski <m.kozlowski@tuxland.pl>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-12-04 22:43:11 +00:00
Al Viro
8e3d8433d8 [NET]: MIPS checksum annotations and cleanups.
* sanitize prototypes, annotate
* kill shift-by-16 in checksum calculations
* htons->shift in l-e checksum calculations

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-02 21:23:09 -08:00
Linus Torvalds
c3e59d1e89 Merge branch 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus
* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus: (31 commits)
  [MIPS] Remove duplicate ISA DMA code for 0 DMA channel case.
  [MIPS] Remove unused definition of cpu_to_lelongp()
  [MIPS] Remove userspace proofing from <asm/bitops.h>.
  [MIPS] Remove old junk left from old atomic_lock.
  [MIPS] Use conditional traps for BUG_ON on MIPS II and better.
  [MIPS] mips HPT cleanup: make clocksource_mips public
  [MIPS] do_IRQ cleanup
  [MIPS] Avoid dupliate D-cache flush on R400C / R4400 SC and MC variants.
  [MIPS] Remove redundant r4k_blast_icache() calls
  [MIPS] Work around bogus gcc warnings.
  [MIPS] Fix double inclusions
  [MIPS] use generic_handle_irq, handle_level_irq, handle_percpu_irq
  [MIPS] IRQ cleanups
  [MIPS] mips hpt cleanup: get rid of mips_hpt_init
  [MIPS] PB1200: Remove duplicate definitions
  [MIPS] Fix alignment hole in struct cache_desc; shrink struct.
  [MIPS] Oprofile: kernel support for the R10000.
  [MIPS] Remove unused R10000 performance counter definitions.
  [MIPS] Add support for kexec
  [MIPS] Don't print presence of WAIT instruction on bootup.
  ...
2006-12-01 16:44:02 -08:00
Benjamin Herrenschmidt
c6dbaef22a Driver core: add dev_archdata to struct device
Add arch specific dev_archdata to struct device

Adds an arch specific struct dev_arch to struct device. This enables
architecture to add specific fields to every device in the system, like
DMA operation pointers, NUMA node ID, firmware specific data, etc...

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Andi Kleen <ak@suse.de>
Acked-By: David Howells <dhowells@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-12-01 14:52:01 -08:00
Ralf Baechle
aa414dff4f [MIPS] Remove duplicate ISA DMA code for 0 DMA channel case.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-11-30 01:14:51 +00:00
Ralf Baechle
0b7883f498 [MIPS] Remove unused definition of cpu_to_lelongp()
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-11-30 01:14:51 +00:00
Ralf Baechle
4ffd8b3838 [MIPS] Remove userspace proofing from <asm/bitops.h>.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-11-30 01:14:50 +00:00
Ralf Baechle
e303e088f2 [MIPS] Remove old junk left from old atomic_lock.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-11-30 01:14:50 +00:00
Ralf Baechle
63dc68a8cf [MIPS] Use conditional traps for BUG_ON on MIPS II and better.
This shaves of around 4kB and a few cycles for the average kernel that
has CONFIG_BUG enabled.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-11-30 01:14:50 +00:00
Atsushi Nemoto
005985609f [MIPS] mips HPT cleanup: make clocksource_mips public
Make clocksource_mips public and get rid of mips_hpt_read,
mips_hpt_mask.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-11-30 01:14:49 +00:00
Atsushi Nemoto
187933f236 [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>
2006-11-30 01:14:49 +00:00
Atsushi Nemoto
1417836e81 [MIPS] use generic_handle_irq, handle_level_irq, handle_percpu_irq
Further incorporation of generic irq framework.  Replacing __do_IRQ()
by proper flow handler would make the irq handling path a bit simpler
and faster.

* use generic_handle_irq() instead of __do_IRQ().
* use handle_level_irq for obvious level-type irq chips.
* use handle_percpu_irq for irqs marked as IRQ_PER_CPU.
* setup .eoi routine for irq chips possibly used with handle_percpu_irq.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-11-30 01:14:46 +00:00
Atsushi Nemoto
1603b5aca4 [MIPS] IRQ cleanups
This is a big irq cleanup patch.

* Use set_irq_chip() to register irq_chip.
* Initialize .mask, .unmask, .mask_ack field.  Functions for these
  method are already exist in most case.
* Do not initialize .startup, .shutdown, .enable, .disable fields if
  default routines provided by irq_chip_set_defaults() were suitable.
* Remove redundant irq_desc initializations.
* Remove unnecessary local_irq_save/local_irq_restore, spin_lock.

With this cleanup, it would be easy to switch to slightly lightwait
irq flow handlers (handle_level_irq(), etc.) instead of __do_IRQ().

Though whole this patch is quite large, changes in each irq_chip are
not quite simple.  Please review and test on your platform.  Thanks.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-11-30 01:14:46 +00:00
Atsushi Nemoto
c87b6ebaea [MIPS] mips hpt cleanup: get rid of mips_hpt_init
Currently nobody outside time.c require mips_hpt_init().  Remove it
and call c0_hpt_timer_init() directly if R4k counter was used for
timer interrupt.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-11-30 01:14:46 +00:00
Ralf Baechle
6f2c3fa022 [MIPS] Fix alignment hole in struct cache_desc; shrink struct.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-11-30 01:14:45 +00:00
Ralf Baechle
2472d0b519 [MIPS] Remove unused R10000 performance counter definitions.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-11-30 01:14:45 +00:00
Nicolas Schichan
583bb86fbb [MIPS] Add support for kexec
A tiny userland application loading the kernel and invoking kexec_load for 
mips is available here:

http://chac.le-poulpe.net/~nico/kexec/kexec-2006-10-18.tar.gz

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-11-30 01:14:44 +00:00
Atsushi Nemoto
656be92f9a [MIPS] Load modules to CKSEG0 if CONFIG_BUILD_ELF64=n
This is a patch to load 64-bit modules to CKSEG0 so that can be
compiled with -msym32 option.  This makes each module ~10% smaller.

* introduce MODULE_START and MODULE_END
* custom module_alloc()
* PGD for modules
* change XTLB refill handler synthesizer
* enable -msym32 for modules again
  (revert ca78b1a5c6a6e70e052d3ea253828e49b5d07c8a)

New XTLB refill handler looks like this:

80000080 dmfc0   k0,C0_BADVADDR
80000084 bltz    k0,800000e4			# goto l_module_alloc
80000088 lui     k1,0x8046			# %high(pgd_current)
8000008c ld      k1,24600(k1)			# %low(pgd_current)
80000090 dsrl    k0,k0,0x1b			# l_vmalloc_done:
80000094 andi    k0,k0,0x1ff8
80000098 daddu   k1,k1,k0
8000009c dmfc0   k0,C0_BADVADDR
800000a0 ld      k1,0(k1)
800000a4 dsrl    k0,k0,0x12
800000a8 andi    k0,k0,0xff8
800000ac daddu   k1,k1,k0
800000b0 dmfc0   k0,C0_XCONTEXT
800000b4 ld      k1,0(k1)
800000b8 andi    k0,k0,0xff0
800000bc daddu   k1,k1,k0
800000c0 ld      k0,0(k1)
800000c4 ld      k1,8(k1)
800000c8 dsrl    k0,k0,0x6
800000cc mtc0    k0,C0_ENTRYLO0
800000d0 dsrl    k1,k1,0x6
800000d4 mtc0    k1,C0_ENTRYL01
800000d8 nop
800000dc tlbwr
800000e0 eret
800000e4 dsll    k1,k0,0x2			# l_module_alloc:
800000e8 bgez    k1,80000008			# goto l_vmalloc
800000ec lui     k1,0xc000
800000f0 dsubu   k0,k0,k1
800000f4 lui     k1,0x8046			# %high(module_pg_dir)
800000f8 beq     zero,zero,80000000
800000fc nop
80000000 beq     zero,zero,80000090		# goto l_vmalloc_done
80000004 daddiu  k1,k1,0x4000
80000008 dsll32  k1,k1,0x0			# l_vmalloc:
8000000c dsubu   k0,k0,k1
80000010 beq     zero,zero,80000090		# goto l_vmalloc_done
80000014 lui     k1,0x8046			# %high(swapper_pg_dir)

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-11-30 01:14:44 +00:00
Yoichi Yuasa
56ae583330 [MIPS] Rewrite GALILEO_INL/GALILEO_OUTL to GT_READ/GT_WRITE
This patch has rewritten GALILEO_INL/GALILEO_OUTL using GT_READ/GT_WRITE.
This patch tested on Cobalt Qube2.

Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-11-30 01:14:43 +00:00
Atsushi Nemoto
4e3884fc83 [MIPS] Use "long" for 64-bit values on 64-bit kernel.
This would get rid of some warnings about "long" vs. "long long".

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-11-30 01:14:43 +00:00
Franck Bui-Huu
8431fd094d [MIPS] Introduce __pa_symbol()
This patch introduces __pa_symbol() macro which should be used to
calculate the physical address of kernel symbols. It also relies
on RELOC_HIDE() to avoid any compiler's oddities when doing
arithmetics on symbols.

Signed-off-by: Franck Bui-Huu <fbuihuu@gmail.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-11-30 01:14:41 +00:00
Franck Bui-Huu
620a4802be [MIPS] Make __pa() aware of XKPHYS/CKSEG0 address mix for 64 bit kernels
During early boot mem init, some configs couldn't use __pa() to
convert virtual into physical addresses. Specially for 64 bit
kernel cases when CONFIG_BUILD_ELF64=n. This patch make __pa()
work for _all_ configs and thus make CPHYSADDR() useless.

Signed-off-by: Franck Bui-Huu <fbuihuu@gmail.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-11-30 01:14:41 +00:00
Franck Bui-Huu
99e3b942c6 [MIPS] page.h: remove __pa() usages.
__pa() was used by virt_to_page() and virt_addr_valid(). These
latter are used when kernel is initialised so __pa() is not
appropriate, we use virt_to_phys() instead.

Futhermore __pa() is going to take care of CKSEG0/XKPHYS
address mix for 64 bit kernels. This makes __pa() more complex
than virt_to_phys() and this extra work is not needed by
virt_to_page() and virt_addr_valid().

Eventually it consolidates virt_to_phys() prototype by making
its argument 'const'. this avoids some warnings that was due
to some virt_to_page() usages which pass const pointer.

Signed-off-by: Franck Bui-Huu <fbuihuu@gmail.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-11-30 01:14:40 +00:00
Manuel Lauss
ec7080d185 [PATCH] make au1xxx-ide compile again
The Au1xx IDE controller driver doesn't compile:

  CC      drivers/ide/mips/au1xxx-ide.o
/linux-2.6.19-rc6-work/drivers/ide/mips/au1xxx-ide.c:480: error: conflicting types for 'auide_ddma_tx_callback'
include2/asm/mach-au1x00/au1xxx_ide.h:174: error: previous declaration of 'auide_ddma_tx_callback' was here
/linux-2.6.19-rc6-work/drivers/ide/mips/au1xxx-ide.c:486: error: conflicting types for 'auide_ddma_rx_callback'
include2/asm/mach-au1x00/au1xxx_ide.h:176: error: previous declaration of 'auide_ddma_rx_callback' was here

Signed-off-by: Manuel Lauss <mano@roarinelk.homelinux.net>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-11-22 23:34:02 +00:00
Ralf Baechle
4a4cf77923 [MIPS] Make irq number allocator generally available for fixing EV64120.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-11-06 20:55:38 +00:00
Ralf Baechle
904880e717 [MIPS] Don't use R10000 llsc workaround version for all llsc-full processors.
Found and original patch by bile@landofbile.com.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-11-02 17:23:33 +00:00
Ralf Baechle
242954b5aa [MIPS] 16K & 64K page size fixes
Derived from Peter Watkins <treestem@gmail.com>'s work.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-11-01 17:46:09 +00:00
Atsushi Nemoto
16b7b2ac01 [MIPS] Fixup migration to GENERIC_TIME
Since we already moved to GENERIC_TIME, we should implement alternatives
of old do_gettimeoffset routines to get sub-jiffies resolution from
gettimeofday().  This patch includes:

 * MIPS clocksource support (based on works by Manish Lachwani).
 * remove unused gettimeoffset routines and related codes.
 * remove unised 64bit do_div64_32().
 * simplify mips_hpt_init. (no argument needed, __init tag)
 * simplify c0_hpt_timer_init. (no need to write to c0_count)
 * remove some hpt_init routines.
 * mips_hpt_mask variable to specify bitmask of hpt value.
 * convert jmr3927_do_gettimeoffset to jmr3927_hpt_read.
 * convert ip27_do_gettimeoffset to ip27_hpt_read.
 * convert bcm1480_do_gettimeoffset to bcm1480_hpt_read.
 * simplify sb1250 hpt functions. (no need to subtract and shift)
    
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-10-31 20:13:23 +00:00
Ralf Baechle
70e46f48cb [MIPS] VSMP: Synchronize cp0 counters on bootup.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-10-31 20:13:22 +00:00
Ralf Baechle
21e9ac7b2d [MIPS] MIPS doesn't need compat_sys_getdents.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-10-30 21:41:31 +00:00
Ralf Baechle
991ea26dcb [MIPS] Wire up getcpu(2) and epoll_wait(2) syscalls.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-10-30 21:41:28 +00:00
Ralf Baechle
f8829caee3 [MIPS] Fix aliasing bug in copy_to_user_page / copy_from_user_page
The current implementation uses a sequence of a cacheflush and a copy.
This is racy in case of a multithreaded debuggee and renders GDB
virtually unusable.

Aside this fixes a performance hog rendering access to /proc/cmdline very
slow and resulting in a enough cache stalls for the 34K AP/SP programming
model to make the bare metal code on the non-Linux VPE miss RT deadlines.

The main part of this patch was originally written by Ralf Baechle;
Atushi Nemoto did the the debugging.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-10-21 23:17:35 +01:00
Ralf Baechle
d89e36d8df [MIPS] Fix iounmap argument to const volatile.
With the existing prototype the following code:

    const void __iomem *io = ioremap();
    x = readb(io);
    iounmap(io);

did result in a warning.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-10-19 17:55:14 +01:00
Ralf Baechle
d2bcf87d0f [MIPS] Reserve syscall numbers for kexec_load.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-10-19 17:55:14 +01:00
Yoichi Yuasa
94399ea62f [MIPS] More vr41xx pt_regs fixups
Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-10-19 17:55:14 +01:00
Linus Torvalds
c25d518044 Merge branch 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus
* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus:
  [MIPS] Pass NULL not 0 for pointer value.
  [MIPS] IP27: Make declaration of setup_replication_mask a proper prototype.
  [MIPS] BigSur: More useful defconfig.
  [MIPS] Cleanup definitions of speed_t and tcflag_t.
  [MIPS] Fix compilation warnings in arch/mips/sibyte/bcm1480/smp.c
  [MIPS] Optimize and cleanup get_saved_sp, set_saved_sp
  [MIPS] <asm/irq.h> does not need pt_regs anymore.
  [MIPS] Workaround for bug in gcc -EB / -EL options.
  [MIPS] Fix timer setup for Jazz
2006-10-11 15:30:14 -07:00
Ralf Baechle
04d4d7d5e3 [MIPS] Cleanup definitions of speed_t and tcflag_t.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-10-11 19:30:59 +01:00
Atsushi Nemoto
9b95e629ea [MIPS] Optimize and cleanup get_saved_sp, set_saved_sp
If CONFIG_BUILD_ELF64 was not selected and gcc had -msym32 option
(i.e. 4.0 or newer), there is no point to use %highest, %higher for
kernel symbols.

This patch also fixes 64-bit SMTC version of get_saved_sp() which is
broken but harmless since there is no such CPUs for now.

A bonus is set_saved_sp() and SMP version of get_saved_sp() are more
readable now.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-10-11 19:30:59 +01:00
Atsushi Nemoto
dff9262ed1 [MIPS] <asm/irq.h> does not need pt_regs anymore.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-10-11 19:30:59 +01:00
Matthew Wilcox
e50190a834 [PATCH] Consolidate check_signature
There's nothing arch-specific about check_signature(), so move it to
<linux/io.h>.  Use a cross between the Alpha and i386 implementations as
the generic one.

Signed-off-by: Matthew Wilcox <willy@parisc-linux.org>
Acked-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-11 11:14:23 -07:00
Atsushi Nemoto
e04582b7bc [MIPS] Make sure cpu_has_fpu is used only in atomic context
Make sure cpu_has_fpu (which uses smp_processor_id()) is used only in
atomic context.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-10-09 23:20:48 +01:00
Ralf Baechle
5536b23514 [MIPS] Alchemy: nuke usbdev; it's useless as is ...
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-10-09 23:20:47 +01:00
David Howells
40220c1a19 IRQ: Use the new typedef for interrupt handler function pointers
Use the new typedef for interrupt handler function pointers rather than
actually spelling out the full thing each time.  This was scripted with the
following small shell script:

#!/bin/sh
egrep -nHrl -e 'irqreturn_t[ 	]*[(][*]' $* |
while read i
do
    echo $i
    perl -pi -e 's/irqreturn_t\s*[(]\s*[*]\s*([_a-zA-Z0-9]*)\s*[)]\s*[(]\s*int\s*,\s*void\s*[*]\s*[)]/irq_handler_t \1/g' $i || exit $?
done

Signed-Off-By: David Howells <dhowells@redhat.com>
2006-10-09 12:19:47 +01:00
Ralf Baechle
6dab2f4564 [MIPS] DEC: pt_regs fixes for buserror handlers
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-10-09 00:15:28 +01:00
Ralf Baechle
937a801576 [MIPS] Complete fixes after removal of pt_regs argument to int handlers.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-10-08 02:38:28 +01:00
David Howells
7d12e780e0 IRQ: Maintain regs pointer globally rather than passing to IRQ handlers
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.

The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around.  On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).

Where appropriate, an arch may override the generic storage facility and do
something different with the variable.  On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.

Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions.  Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller.  A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.

I've build this code with allyesconfig for x86_64 and i386.  I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.

This will affect all archs.  Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:

	struct pt_regs *old_regs = set_irq_regs(regs);

And put the old one back at the end:

	set_irq_regs(old_regs);

Don't pass regs through to generic_handle_irq() or __do_IRQ().

In timer_interrupt(), this sort of change will be necessary:

	-	update_process_times(user_mode(regs));
	-	profile_tick(CPU_PROFILING, regs);
	+	update_process_times(user_mode(get_irq_regs()));
	+	profile_tick(CPU_PROFILING);

I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().

Some notes on the interrupt handling in the drivers:

 (*) input_dev() is now gone entirely.  The regs pointer is no longer stored in
     the input_dev struct.

 (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking.  It does
     something different depending on whether it's been supplied with a regs
     pointer or not.

 (*) Various IRQ handler function pointers have been moved to type
     irq_handler_t.

Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 15:10:12 +01:00