summaryrefslogtreecommitdiff
path: root/arch/powerpc/kernel/fpu.S
diff options
context:
space:
mode:
Diffstat (limited to 'arch/powerpc/kernel/fpu.S')
-rw-r--r--arch/powerpc/kernel/fpu.S14
1 files changed, 8 insertions, 6 deletions
diff --git a/arch/powerpc/kernel/fpu.S b/arch/powerpc/kernel/fpu.S
index 4dca05e..f7f5b8b 100644
--- a/arch/powerpc/kernel/fpu.S
+++ b/arch/powerpc/kernel/fpu.S
@@ -106,6 +106,8 @@ _GLOBAL(store_fp_state)
* and save its floating-point registers in its thread_struct.
* Load up this task's FP registers from its thread_struct,
* enable the FPU for the current task and return to the task.
+ * Note that on 32-bit this can only use registers that will be
+ * restored by fast_exception_return, i.e. r3 - r6, r10 and r11.
*/
_GLOBAL(load_up_fpu)
mfmsr r5
@@ -131,10 +133,10 @@ END_FTR_SECTION_IFSET(CPU_FTR_VSX)
beq 1f
toreal(r4)
addi r4,r4,THREAD /* want last_task_used_math->thread */
- addi r8,r4,THREAD_FPSTATE
- SAVE_32FPVSRS(0, R5, R8)
+ addi r10,r4,THREAD_FPSTATE
+ SAVE_32FPVSRS(0, R5, R10)
mffs fr0
- stfd fr0,FPSTATE_FPSCR(r8)
+ stfd fr0,FPSTATE_FPSCR(r10)
PPC_LL r5,PT_REGS(r4)
toreal(r5)
PPC_LL r4,_MSR-STACK_FRAME_OVERHEAD(r5)
@@ -157,10 +159,10 @@ END_FTR_SECTION_IFSET(CPU_FTR_VSX)
or r12,r12,r4
std r12,_MSR(r1)
#endif
- addi r7,r5,THREAD_FPSTATE
- lfd fr0,FPSTATE_FPSCR(r7)
+ addi r10,r5,THREAD_FPSTATE
+ lfd fr0,FPSTATE_FPSCR(r10)
MTFSF_L(fr0)
- REST_32FPVSRS(0, R4, R7)
+ REST_32FPVSRS(0, R4, R10)
#ifndef CONFIG_SMP
subi r4,r5,THREAD
fromreal(r4)