diff options
| author | Michael Neuling <mikey@neuling.org> | 2008-06-25 14:07:18 +1000 |
|---|---|---|
| committer | Paul Mackerras <paulus@samba.org> | 2008-07-01 11:28:50 +1000 |
| commit | ce48b2100785e5ca629fb3aa8e3b50aca808f692 (patch) | |
| tree | 63532ff7cc68b18ca4902bd10e03fcbaaf01cade /arch/powerpc/kernel/misc_64.S | |
| parent | 72ffff5b1792b0fa4d40a8e2f3276fff999820ec (diff) | |
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/misc_64.S')
| -rw-r--r-- | arch/powerpc/kernel/misc_64.S | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/misc_64.S b/arch/powerpc/kernel/misc_64.S index 942951e7658..31b9026cf1e 100644 --- a/arch/powerpc/kernel/misc_64.S +++ b/arch/powerpc/kernel/misc_64.S @@ -506,6 +506,39 @@ _GLOBAL(giveup_altivec) #endif /* CONFIG_ALTIVEC */ +#ifdef CONFIG_VSX +/* + * giveup_vsx(tsk) + * Disable VSX for the task given as the argument, + * and save the vector registers in its thread_struct. + * Enables the VSX for use in the kernel on return. + */ +_GLOBAL(giveup_vsx) + mfmsr r5 + oris r5,r5,MSR_VSX@h + mtmsrd r5 /* enable use of VSX now */ + isync + + cmpdi 0,r3,0 + beqlr- /* if no previous owner, done */ + addi r3,r3,THREAD /* want THREAD of task */ + ld r5,PT_REGS(r3) + cmpdi 0,r5,0 + beq 1f + ld r4,_MSR-STACK_FRAME_OVERHEAD(r5) + lis r3,MSR_VSX@h + andc r4,r4,r3 /* disable VSX for previous task */ + std r4,_MSR-STACK_FRAME_OVERHEAD(r5) +1: +#ifndef CONFIG_SMP + li r5,0 + ld r4,last_task_used_vsx@got(r2) + std r5,0(r4) +#endif /* CONFIG_SMP */ + blr + +#endif /* CONFIG_VSX */ + /* kexec_wait(phys_cpu) * * wait for the flag to change, indicating this kernel is going away but |