From ce48b2100785e5ca629fb3aa8e3b50aca808f692 Mon Sep 17 00:00:00 2001 From: Michael Neuling Date: Wed, 25 Jun 2008 14:07:18 +1000 Subject: 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 Signed-off-by: Paul Mackerras --- arch/powerpc/kernel/misc_64.S | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) (limited to 'arch/powerpc/kernel/misc_64.S') diff --git a/arch/powerpc/kernel/misc_64.S b/arch/powerpc/kernel/misc_64.S index 942951e76586..31b9026cf1e3 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 -- cgit v1.2.2