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>

1 files changed, 9 insertions, 0 deletions

diff --git a/include/asm-powerpc/system.h b/include/asm-powerpc/system.h
index 2642a92b724f..0c12c66733f6 100644
--- a/include/asm-powerpc/system.h
+++ b/include/asm-powerpc/system.h
@@ -139,6 +139,7 @@ extern void enable_kernel_altivec(void);
 extern void giveup_altivec(struct task_struct *);
 extern void load_up_altivec(struct task_struct *);
 extern int emulate_altivec(struct pt_regs *);
+extern void giveup_vsx(struct task_struct *);
 extern void enable_kernel_spe(void);
 extern void giveup_spe(struct task_struct *);
 extern void load_up_spe(struct task_struct *);
@@ -162,6 +163,14 @@ static inline void flush_altivec_to_thread(struct task_struct *t)
 }
 #endif
 
+#ifdef CONFIG_VSX
+extern void flush_vsx_to_thread(struct task_struct *);
+#else
+static inline void flush_vsx_to_thread(struct task_struct *t)
+{
+}
+#endif
+
 #ifdef CONFIG_SPE
 extern void flush_spe_to_thread(struct task_struct *);
 #else