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| author | Michael Neuling <mikey@neuling.org> | 2008-06-25 08:07:18 +0400 |
|---|---|---|
| committer | Paul Mackerras <paulus@samba.org> | 2008-07-01 05:28:50 +0400 |
| commit | ce48b2100785e5ca629fb3aa8e3b50aca808f692 (patch) | |
| tree | 63532ff7cc68b18ca4902bd10e03fcbaaf01cade /arch/powerpc/kernel/head_64.S | |
| parent | 72ffff5b1792b0fa4d40a8e2f3276fff999820ec (diff) | |
| download | linux-ce48b2100785e5ca629fb3aa8e3b50aca808f692.tar.xz | |
powerpc: Add VSX context save/restore, ptrace and signal support
This patch extends the floating point save and restore code to use the
VSX load/stores when VSX is available. This will make FP context
save/restore marginally slower on FP only code, when VSX is available,
as it has to load/store 128bits rather than just 64bits.
Mixing FP, VMX and VSX code will get constant architected state.
The signals interface is extended to enable access to VSR 0-31
doubleword 1 after discussions with tool chain maintainers. Backward
compatibility is maintained.
The ptrace interface is also extended to allow access to VSR 0-31 full
registers.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Diffstat (limited to 'arch/powerpc/kernel/head_64.S')
| -rw-r--r-- | arch/powerpc/kernel/head_64.S | 65 |
1 files changed, 65 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/head_64.S b/arch/powerpc/kernel/head_64.S index 64433731d995..ecced1eb03ae 100644 --- a/arch/powerpc/kernel/head_64.S +++ b/arch/powerpc/kernel/head_64.S @@ -278,6 +278,9 @@ END_FTR_SECTION_IFSET(CPU_FTR_REAL_LE) . = 0xf20 b altivec_unavailable_pSeries + . = 0xf40 + b vsx_unavailable_pSeries + #ifdef CONFIG_CBE_RAS HSTD_EXCEPTION_PSERIES(0x1200, cbe_system_error) #endif /* CONFIG_CBE_RAS */ @@ -297,6 +300,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_REAL_LE) /* moved from 0xf00 */ STD_EXCEPTION_PSERIES(., performance_monitor) STD_EXCEPTION_PSERIES(., altivec_unavailable) + STD_EXCEPTION_PSERIES(., vsx_unavailable) /* * An interrupt came in while soft-disabled; clear EE in SRR1, @@ -836,6 +840,67 @@ _STATIC(load_up_altivec) blr #endif /* CONFIG_ALTIVEC */ + .align 7 + .globl vsx_unavailable_common +vsx_unavailable_common: + EXCEPTION_PROLOG_COMMON(0xf40, PACA_EXGEN) +#ifdef CONFIG_VSX +BEGIN_FTR_SECTION + bne .load_up_vsx +1: +END_FTR_SECTION_IFSET(CPU_FTR_VSX) +#endif + bl .save_nvgprs + addi r3,r1,STACK_FRAME_OVERHEAD + ENABLE_INTS + bl .vsx_unavailable_exception + b .ret_from_except + +#ifdef CONFIG_VSX +/* + * load_up_vsx(unused, unused, tsk) + * Disable VSX for the task which had it previously, + * and save its vector registers in its thread_struct. + * Reuse the fp and vsx saves, but first check to see if they have + * been saved already. + * On entry: r13 == 'current' && last_task_used_vsx != 'current' + */ +_STATIC(load_up_vsx) +/* Load FP and VSX registers if they haven't been done yet */ + andi. r5,r12,MSR_FP + beql+ load_up_fpu /* skip if already loaded */ + andis. r5,r12,MSR_VEC@h + beql+ load_up_altivec /* skip if already loaded */ + +#ifndef CONFIG_SMP + ld r3,last_task_used_vsx@got(r2) + ld r4,0(r3) + cmpdi 0,r4,0 + beq 1f + /* Disable VSX for last_task_used_vsx */ + addi r4,r4,THREAD + ld r5,PT_REGS(r4) + ld r4,_MSR-STACK_FRAME_OVERHEAD(r5) + lis r6,MSR_VSX@h + andc r6,r4,r6 + std r6,_MSR-STACK_FRAME_OVERHEAD(r5) +1: +#endif /* CONFIG_SMP */ + ld r4,PACACURRENT(r13) + addi r4,r4,THREAD /* Get THREAD */ + li r6,1 + stw r6,THREAD_USED_VSR(r4) /* ... also set thread used vsr */ + /* enable use of VSX after return */ + oris r12,r12,MSR_VSX@h + std r12,_MSR(r1) +#ifndef CONFIG_SMP + /* Update last_task_used_math to 'current' */ + ld r4,PACACURRENT(r13) + std r4,0(r3) +#endif /* CONFIG_SMP */ + b fast_exception_return +#endif /* CONFIG_VSX */ + /* * Hash table stuff */ |