The idle loop goes to sleep using the WAIT instruction if !need_resched().
This has is suffering from from a race condition that if if just after
need_resched has returned 0 an interrupt might set TIF_NEED_RESCHED but
we've just completed the test so go to sleep anyway. This would be
trivial to fix by just disabling interrupts during that sequence as in:
local_irq_disable();
if (!need_resched())
__asm__("wait");
local_irq_enable();
but the processor architecture leaves it undefined if a processor calling
WAIT with interrupts disabled will ever restart its pipeline and indeed
some processors have made use of the freedom provided by the architecture
definition. This has been resolved and the Config7.WII bit indicates that
the use of WAIT is safe on 24K, 24KE and 34K cores. It also is safe on
74K starting revision 2.1.0 so enable the use of WAIT with interrupts
disabled for 74K based on a c0_prid of at least that.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Older processors used to encode processor version and revision in two
4-bit bitfields, the 4K seems to simply count up and even newer MTI cores
have switched to use the 8-bits as 3:3:2 bitfield with the last field as
the patch number.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The RM7000 processors and the E9000 cores have a bug (though PMC-Sierra
opposes it being called that) where invalid instructions in the same
I-cache line worth of instructions being fetched may case spurious
exceptions.
The workaround for this was only enabled for E9000 cores; enable it also
for all RM7000-based platforms.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This marks the declaration of die() correctly, removing "control reaches
end of non-void function" warnings from non-void functions that die() at
the end.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Some IP35 defines snuck into some IP32-specific code during the DMA re-write.
Signed-off-by: Joshua Kinard <kumba@gentoo.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Fix a sparse warning caused by 2c921d07f8c641e691b0dfd80a5cfe14c60ec489
include2/asm/bitops.h:313:23: warning: symbol 'res' shadows an earlier one
include2/asm/bitops.h:309:16: originally declared here
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
For some platforms it's definitions may conflict. So that's the one-liner.
The rest is 10 square kilometers of collateral damage fixup this include
used to paper over.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
And an attempt to tidy up the core/controller differences.
Signed-off-by: Chris Dearman <chris@mips.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This must be the oldest bug that we have got. Leaving interrupts "as
they are" for the R3000 obviously means copying IEp to IEc. Since we have
got STATMASK now, I took this opportunity to mask the status register
"correctly" for the R3000 now too. Oh, and the R3000 hardly ever is
64-bit.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
sys_fadvise64() is not used on MIPS. The libc can implement
both posix_fadvise() and posix_fadvise64() using sys_fadvise64_64().
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Aside of being handy for debugging this has never been a particularly
good idea but is now getting in the way of dyntick / tickless kernels
and general cleanups.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
First thing mm.h does is including sched.h solely for can_do_mlock() inline
function which has "current" dereference inside. By dealing with can_do_mlock()
mm.h can be detached from sched.h which is good. See below, why.
This patch
a) removes unconditional inclusion of sched.h from mm.h
b) makes can_do_mlock() normal function in mm/mlock.c
c) exports can_do_mlock() to not break compilation
d) adds sched.h inclusions back to files that were getting it indirectly.
e) adds less bloated headers to some files (asm/signal.h, jiffies.h) that were
getting them indirectly
Net result is:
a) mm.h users would get less code to open, read, preprocess, parse, ... if
they don't need sched.h
b) sched.h stops being dependency for significant number of files:
on x86_64 allmodconfig touching sched.h results in recompile of 4083 files,
after patch it's only 3744 (-8.3%).
Cross-compile tested on
all arm defconfigs, all mips defconfigs, all powerpc defconfigs,
alpha alpha-up
arm
i386 i386-up i386-defconfig i386-allnoconfig
ia64 ia64-up
m68k
mips
parisc parisc-up
powerpc powerpc-up
s390 s390-up
sparc sparc-up
sparc64 sparc64-up
um-x86_64
x86_64 x86_64-up x86_64-defconfig x86_64-allnoconfig
as well as my two usual configs.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus: (28 commits)
[MIPS] Rework cobalt_board_id
[MIPS] Use RTC_CMOS for Cobalt
[MIPS] Use platform_device for Cobalt UART
[MIPS] Separate Alchemy processor based boards config
[MIPS] Fix build error in atomic64_cmpxchg
[MIPS] Run checksyscalls for N32 and O32 ABI
[MIPS] tlbex: use __maybe_unused
[MIPS] excite: use __maybe_unused
[MIPS] Add extern cobalt_board_id
[MIPS] Remove unused CONFIG_TOSHIBA_BOARDS
[MIPS] Rename tb0229_defconfig to tb0219_defconfig
[MIPS] Update tb0229_defconfig; add CONFIG_GPIO_TB0219.
[MIPS] Add minimum defconfig for RBHMA4200
[MIPS] SB1: Build fix.
[MIPS] Drop __devinit tag from allocate_irqno() and free_irqno()
[MIPS] clocksource: use CLOCKSOURCE_MASK() macro
[MIPS] Remove LIMITED_DMA support
[MIPS] Remove Momenco Jaguar ATX support
[MIPS] Remove Momenco Ocelot G support
[MIPS] FPU hazard handling
...
These files are almost all the same.
This patch could be made even simpler if we don't mind POLLREMOVE turning
up in a few architectures that didn't have it previously (which should be
OK as POLLREMOVE is not used anywhere in the current tree).
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ralf Baechle
Andrew Sharp
Atsushi Nemoto
Maciej W. Rozycki
Kumba
Ralf Baechle
Pavel Kiryukhin
Chris Dearman
Alexey Dobriyan
Linus Torvalds
Stephen Rothwell
Yoichi Yuasa