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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2012-11-11 00:58:34 +0400 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-11-11 00:58:34 +0400 |
| commit | 2b1768f39aebfcccdc5b948eb4962918a5a64581 (patch) | |
| tree | f92c98ef10cf1ded4985050589413946aa8f0e6c /arch/sparc/include/asm/processor_64.h | |
| parent | affd9a8dbc22beadae1186aa060685d6f6a06792 (diff) | |
| parent | 226f7cea949303a3e1911999a9a2c71b0a708e73 (diff) | |
| download | linux-2b1768f39aebfcccdc5b948eb4962918a5a64581.tar.xz | |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc
Pull sparc fixes from David Miller:
"Several build/bug fixes for sparc, including:
1) Configuring a mix of static vs. modular sparc64 crypto modules
didn't work, remove an ill-conceived attempt to only have to build
the device match table for these drivers once to fix the problem.
Reported by Meelis Roos.
2) Make the montgomery multiple/square and mpmul instructions actually
usable in 32-bit tasks. Essentially this involves providing 32-bit
userspace with a way to use a 64-bit stack when it needs to.
3) Our sparc64 atomic backoffs don't yield cpu strands properly on
Niagara chips. Use pause instruction when available to achieve
this, otherwise use a benign instruction we know blocks the strand
for some time.
4) Wire up kcmp
5) Fix the build of various drivers by removing the unnecessary
blocking of OF_GPIO when SPARC.
6) Fix unintended regression wherein of_address_to_resource stopped
being provided. Fix from Andreas Larsson.
7) Fix NULL dereference in leon_handle_ext_irq(), also from Andreas
Larsson."
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
sparc64: Fix build with mix of modular vs. non-modular crypto drivers.
sparc: Support atomic64_dec_if_positive properly.
of/address: sparc: Declare of_address_to_resource() as an extern function for sparc again
sparc32, leon: Check for existent irq_map entry in leon_handle_ext_irq
sparc: Add sparc support for platform_get_irq()
sparc: Allow OF_GPIO on sparc.
qlogicpti: Fix build warning.
sparc: Wire up sys_kcmp.
sparc64: Improvde documentation and readability of atomic backoff code.
sparc64: Use pause instruction when available.
sparc64: Fix cpu strand yielding.
sparc64: Make montmul/montsqr/mpmul usable in 32-bit threads.
Diffstat (limited to 'arch/sparc/include/asm/processor_64.h')
| -rw-r--r-- | arch/sparc/include/asm/processor_64.h | 17 |
1 files changed, 16 insertions, 1 deletions
diff --git a/arch/sparc/include/asm/processor_64.h b/arch/sparc/include/asm/processor_64.h index 4e5a483122a0..721e25f0e2ea 100644 --- a/arch/sparc/include/asm/processor_64.h +++ b/arch/sparc/include/asm/processor_64.h @@ -196,7 +196,22 @@ extern unsigned long get_wchan(struct task_struct *task); #define KSTK_EIP(tsk) (task_pt_regs(tsk)->tpc) #define KSTK_ESP(tsk) (task_pt_regs(tsk)->u_regs[UREG_FP]) -#define cpu_relax() barrier() +/* Please see the commentary in asm/backoff.h for a description of + * what these instructions are doing and how they have been choosen. + * To make a long story short, we are trying to yield the current cpu + * strand during busy loops. + */ +#define cpu_relax() asm volatile("\n99:\n\t" \ + "rd %%ccr, %%g0\n\t" \ + "rd %%ccr, %%g0\n\t" \ + "rd %%ccr, %%g0\n\t" \ + ".section .pause_3insn_patch,\"ax\"\n\t"\ + ".word 99b\n\t" \ + "wr %%g0, 128, %%asr27\n\t" \ + "nop\n\t" \ + "nop\n\t" \ + ".previous" \ + ::: "memory") /* Prefetch support. This is tuned for UltraSPARC-III and later. * UltraSPARC-I will treat these as nops, and UltraSPARC-II has |