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-rw-r--r--arch/powerpc/kernel/fpu.S86
1 files changed, 39 insertions, 47 deletions
diff --git a/arch/powerpc/kernel/fpu.S b/arch/powerpc/kernel/fpu.S
index caeaabf11a2f..f7f5b8bed68f 100644
--- a/arch/powerpc/kernel/fpu.S
+++ b/arch/powerpc/kernel/fpu.S
@@ -35,15 +35,6 @@ END_FTR_SECTION_IFSET(CPU_FTR_VSX); \
2: REST_32VSRS(n,c,base); \
3:
-#define __REST_32FPVSRS_TRANSACT(n,c,base) \
-BEGIN_FTR_SECTION \
- b 2f; \
-END_FTR_SECTION_IFSET(CPU_FTR_VSX); \
- REST_32FPRS_TRANSACT(n,base); \
- b 3f; \
-2: REST_32VSRS_TRANSACT(n,c,base); \
-3:
-
#define __SAVE_32FPVSRS(n,c,base) \
BEGIN_FTR_SECTION \
b 2f; \
@@ -54,40 +45,12 @@ END_FTR_SECTION_IFSET(CPU_FTR_VSX); \
3:
#else
#define __REST_32FPVSRS(n,b,base) REST_32FPRS(n, base)
-#define __REST_32FPVSRS_TRANSACT(n,b,base) REST_32FPRS(n, base)
#define __SAVE_32FPVSRS(n,b,base) SAVE_32FPRS(n, base)
#endif
#define REST_32FPVSRS(n,c,base) __REST_32FPVSRS(n,__REG_##c,__REG_##base)
-#define REST_32FPVSRS_TRANSACT(n,c,base) \
- __REST_32FPVSRS_TRANSACT(n,__REG_##c,__REG_##base)
#define SAVE_32FPVSRS(n,c,base) __SAVE_32FPVSRS(n,__REG_##c,__REG_##base)
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
-/*
- * Wrapper to call load_up_fpu from C.
- * void do_load_up_fpu(struct pt_regs *regs);
- */
-_GLOBAL(do_load_up_fpu)
- mflr r0
- std r0, 16(r1)
- stdu r1, -112(r1)
-
- subi r6, r3, STACK_FRAME_OVERHEAD
- /* load_up_fpu expects r12=MSR, r13=PACA, and returns
- * with r12 = new MSR.
- */
- ld r12,_MSR(r6)
- GET_PACA(r13)
-
- bl load_up_fpu
- std r12,_MSR(r6)
-
- ld r0, 112+16(r1)
- addi r1, r1, 112
- mtlr r0
- blr
-
-
/* void do_load_up_transact_fpu(struct thread_struct *thread)
*
* This is similar to load_up_fpu but for the transactional version of the FP
@@ -105,9 +68,10 @@ END_FTR_SECTION_IFSET(CPU_FTR_VSX)
SYNC
MTMSRD(r5)
- lfd fr0,THREAD_TRANSACT_FPSCR(r3)
+ addi r7,r3,THREAD_TRANSACT_FPSTATE
+ lfd fr0,FPSTATE_FPSCR(r7)
MTFSF_L(fr0)
- REST_32FPVSRS_TRANSACT(0, R4, R3)
+ REST_32FPVSRS(0, R4, R7)
/* FP/VSX off again */
MTMSRD(r6)
@@ -117,11 +81,33 @@ END_FTR_SECTION_IFSET(CPU_FTR_VSX)
#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
/*
+ * Load state from memory into FP registers including FPSCR.
+ * Assumes the caller has enabled FP in the MSR.
+ */
+_GLOBAL(load_fp_state)
+ lfd fr0,FPSTATE_FPSCR(r3)
+ MTFSF_L(fr0)
+ REST_32FPVSRS(0, R4, R3)
+ blr
+
+/*
+ * Store FP state into memory, including FPSCR
+ * Assumes the caller has enabled FP in the MSR.
+ */
+_GLOBAL(store_fp_state)
+ SAVE_32FPVSRS(0, R4, R3)
+ mffs fr0
+ stfd fr0,FPSTATE_FPSCR(r3)
+ blr
+
+/*
* This task wants to use the FPU now.
* On UP, disable FP for the task which had the FPU previously,
* 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
@@ -147,9 +133,10 @@ END_FTR_SECTION_IFSET(CPU_FTR_VSX)
beq 1f
toreal(r4)
addi r4,r4,THREAD /* want last_task_used_math->thread */
- SAVE_32FPVSRS(0, R5, R4)
+ addi r10,r4,THREAD_FPSTATE
+ SAVE_32FPVSRS(0, R5, R10)
mffs fr0
- stfd fr0,THREAD_FPSCR(r4)
+ stfd fr0,FPSTATE_FPSCR(r10)
PPC_LL r5,PT_REGS(r4)
toreal(r5)
PPC_LL r4,_MSR-STACK_FRAME_OVERHEAD(r5)
@@ -160,7 +147,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_VSX)
#endif /* CONFIG_SMP */
/* enable use of FP after return */
#ifdef CONFIG_PPC32
- mfspr r5,SPRN_SPRG_THREAD /* current task's THREAD (phys) */
+ mfspr r5,SPRN_SPRG_THREAD /* current task's THREAD (phys) */
lwz r4,THREAD_FPEXC_MODE(r5)
ori r9,r9,MSR_FP /* enable FP for current */
or r9,r9,r4
@@ -172,9 +159,10 @@ END_FTR_SECTION_IFSET(CPU_FTR_VSX)
or r12,r12,r4
std r12,_MSR(r1)
#endif
- lfd fr0,THREAD_FPSCR(r5)
+ addi r10,r5,THREAD_FPSTATE
+ lfd fr0,FPSTATE_FPSCR(r10)
MTFSF_L(fr0)
- REST_32FPVSRS(0, R4, R5)
+ REST_32FPVSRS(0, R4, R10)
#ifndef CONFIG_SMP
subi r4,r5,THREAD
fromreal(r4)
@@ -206,11 +194,15 @@ END_FTR_SECTION_IFSET(CPU_FTR_VSX)
PPC_LCMPI 0,r3,0
beqlr- /* if no previous owner, done */
addi r3,r3,THREAD /* want THREAD of task */
+ PPC_LL r6,THREAD_FPSAVEAREA(r3)
PPC_LL r5,PT_REGS(r3)
- PPC_LCMPI 0,r5,0
- SAVE_32FPVSRS(0, R4 ,R3)
+ PPC_LCMPI 0,r6,0
+ bne 2f
+ addi r6,r3,THREAD_FPSTATE
+2: PPC_LCMPI 0,r5,0
+ SAVE_32FPVSRS(0, R4, R6)
mffs fr0
- stfd fr0,THREAD_FPSCR(r3)
+ stfd fr0,FPSTATE_FPSCR(r6)
beq 1f
PPC_LL r4,_MSR-STACK_FRAME_OVERHEAD(r5)
li r3,MSR_FP|MSR_FE0|MSR_FE1
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