powerpc: Remove fpscr use from [kvm_]cvt_{fd,df}

Neither lfs nor stfs touch the fpscr, so remove the restore/save of it
around them.

Signed-off-by: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

6 files changed, 26 insertions, 48 deletions

diff --git a/arch/powerpc/include/asm/kvm_fpu.h b/arch/powerpc/include/asm/kvm_fpu.h
index c3d4f0518a67..92daae132492 100644
--- a/arch/powerpc/include/asm/kvm_fpu.h
+++ b/arch/powerpc/include/asm/kvm_fpu.h
@@ -82,7 +82,7 @@ FPD_THREE_IN(fmadd)
 FPD_THREE_IN(fnmsub)
 FPD_THREE_IN(fnmadd)
 
-extern void kvm_cvt_fd(u32 *from, u64 *to, u64 *fpscr);
-extern void kvm_cvt_df(u64 *from, u32 *to, u64 *fpscr);
+extern void kvm_cvt_fd(u32 *from, u64 *to);
+extern void kvm_cvt_df(u64 *from, u32 *to);
 
 #endif
diff --git a/arch/powerpc/include/asm/system.h b/arch/powerpc/include/asm/system.h
index 6c294acac848..0b3fe78be71b 100644
--- a/arch/powerpc/include/asm/system.h
+++ b/arch/powerpc/include/asm/system.h
@@ -154,8 +154,8 @@ extern void enable_kernel_spe(void);
 extern void giveup_spe(struct task_struct *);
 extern void load_up_spe(struct task_struct *);
 extern int fix_alignment(struct pt_regs *);
-extern void cvt_fd(float *from, double *to, struct thread_struct *thread);
-extern void cvt_df(double *from, float *to, struct thread_struct *thread);
+extern void cvt_fd(float *from, double *to);
+extern void cvt_df(double *from, float *to);
 
 #ifndef CONFIG_SMP
 extern void discard_lazy_cpu_state(void);
diff --git a/arch/powerpc/kernel/align.c b/arch/powerpc/kernel/align.c
index b876e989220b..8184ee97e484 100644
--- a/arch/powerpc/kernel/align.c
+++ b/arch/powerpc/kernel/align.c
@@ -889,7 +889,7 @@ int fix_alignment(struct pt_regs *regs)
 #ifdef CONFIG_PPC_FPU
                         preempt_disable();
                         enable_kernel_fp();
-                        cvt_df(&data.dd, (float *)&data.v[4], &current->thread);
+                        cvt_df(&data.dd, (float *)&data.v[4]);
                         preempt_enable();
 #else
                         return 0;
@@ -933,7 +933,7 @@ int fix_alignment(struct pt_regs *regs)
 #ifdef CONFIG_PPC_FPU
                 preempt_disable();
                 enable_kernel_fp();
-                cvt_fd((float *)&data.v[4], &data.dd, &current->thread);
+                cvt_fd((float *)&data.v[4], &data.dd);
                 preempt_enable();
 #else
                 return 0;
diff --git a/arch/powerpc/kernel/fpu.S b/arch/powerpc/kernel/fpu.S
index fc8f5b14019c..e86c040ae585 100644
--- a/arch/powerpc/kernel/fpu.S
+++ b/arch/powerpc/kernel/fpu.S
@@ -163,24 +163,14 @@ END_FTR_SECTION_IFSET(CPU_FTR_VSX)
 /*
  * These are used in the alignment trap handler when emulating
  * single-precision loads and stores.
- * We restore and save the fpscr so the task gets the same result
- * and exceptions as if the cpu had performed the load or store.
  */
 
 _GLOBAL(cvt_fd)
-        lfd     0,THREAD_FPSCR(r5)      /* load up fpscr value */
-        MTFSF_L(0)
         lfs     0,0(r3)
         stfd    0,0(r4)
-        mffs    0
-        stfd    0,THREAD_FPSCR(r5)      /* save new fpscr value */
         blr
 
 _GLOBAL(cvt_df)
-        lfd     0,THREAD_FPSCR(r5)      /* load up fpscr value */
-        MTFSF_L(0)
         lfd     0,0(r3)
         stfs    0,0(r4)
-        mffs    0
-        stfd    0,THREAD_FPSCR(r5)      /* save new fpscr value */
         blr
diff --git a/arch/powerpc/kvm/book3s_paired_singles.c b/arch/powerpc/kvm/book3s_paired_singles.c
index 474f2e24050a..35a701f3ece4 100644
--- a/arch/powerpc/kvm/book3s_paired_singles.c
+++ b/arch/powerpc/kvm/book3s_paired_singles.c
@@ -159,7 +159,7 @@
 
 static inline void kvmppc_sync_qpr(struct kvm_vcpu *vcpu, int rt)
 {
-        kvm_cvt_df(&vcpu->arch.fpr[rt], &vcpu->arch.qpr[rt], &vcpu->arch.fpscr);
+        kvm_cvt_df(&vcpu->arch.fpr[rt], &vcpu->arch.qpr[rt]);
 }
 
 static void kvmppc_inject_pf(struct kvm_vcpu *vcpu, ulong eaddr, bool is_store)
@@ -204,7 +204,7 @@ static int kvmppc_emulate_fpr_load(struct kvm_run *run, struct kvm_vcpu *vcpu,
         /* put in registers */
         switch (ls_type) {
         case FPU_LS_SINGLE:
-                kvm_cvt_fd((u32*)tmp, &vcpu->arch.fpr[rs], &vcpu->arch.fpscr);
+                kvm_cvt_fd((u32*)tmp, &vcpu->arch.fpr[rs]);
                 vcpu->arch.qpr[rs] = *((u32*)tmp);
                 break;
         case FPU_LS_DOUBLE:
@@ -230,7 +230,7 @@ static int kvmppc_emulate_fpr_store(struct kvm_run *run, struct kvm_vcpu *vcpu,
 
         switch (ls_type) {
         case FPU_LS_SINGLE:
-                kvm_cvt_df(&vcpu->arch.fpr[rs], (u32*)tmp, &vcpu->arch.fpscr);
+                kvm_cvt_df(&vcpu->arch.fpr[rs], (u32*)tmp);
                 val = *((u32*)tmp);
                 len = sizeof(u32);
                 break;
@@ -296,7 +296,7 @@ static int kvmppc_emulate_psq_load(struct kvm_run *run, struct kvm_vcpu *vcpu,
         emulated = EMULATE_DONE;
 
         /* put in registers */
-        kvm_cvt_fd(&tmp[0], &vcpu->arch.fpr[rs], &vcpu->arch.fpscr);
+        kvm_cvt_fd(&tmp[0], &vcpu->arch.fpr[rs]);
         vcpu->arch.qpr[rs] = tmp[1];
 
         dprintk(KERN_INFO "KVM: PSQ_LD [0x%x, 0x%x] at 0x%lx (%d)\n", tmp[0],
@@ -314,7 +314,7 @@ static int kvmppc_emulate_psq_store(struct kvm_run *run, struct kvm_vcpu *vcpu,
         u32 tmp[2];
         int len = w ? sizeof(u32) : sizeof(u64);
 
-        kvm_cvt_df(&vcpu->arch.fpr[rs], &tmp[0], &vcpu->arch.fpscr);
+        kvm_cvt_df(&vcpu->arch.fpr[rs], &tmp[0]);
         tmp[1] = vcpu->arch.qpr[rs];
 
         r = kvmppc_st(vcpu, &addr, len, tmp, true);
@@ -516,9 +516,9 @@ static int kvmppc_ps_three_in(struct kvm_vcpu *vcpu, bool rc,
         WARN_ON(rc);
 
         /* PS0 */
-        kvm_cvt_df(&fpr[reg_in1], &ps0_in1, &vcpu->arch.fpscr);
-        kvm_cvt_df(&fpr[reg_in2], &ps0_in2, &vcpu->arch.fpscr);
-        kvm_cvt_df(&fpr[reg_in3], &ps0_in3, &vcpu->arch.fpscr);
+        kvm_cvt_df(&fpr[reg_in1], &ps0_in1);
+        kvm_cvt_df(&fpr[reg_in2], &ps0_in2);
+        kvm_cvt_df(&fpr[reg_in3], &ps0_in3);
 
         if (scalar & SCALAR_LOW)
                 ps0_in2 = qpr[reg_in2];
@@ -529,7 +529,7 @@ static int kvmppc_ps_three_in(struct kvm_vcpu *vcpu, bool rc,
                           ps0_in1, ps0_in2, ps0_in3, ps0_out);
 
         if (!(scalar & SCALAR_NO_PS0))
-                kvm_cvt_fd(&ps0_out, &fpr[reg_out], &vcpu->arch.fpscr);
+                kvm_cvt_fd(&ps0_out, &fpr[reg_out]);
 
         /* PS1 */
         ps1_in1 = qpr[reg_in1];
@@ -566,12 +566,12 @@ static int kvmppc_ps_two_in(struct kvm_vcpu *vcpu, bool rc,
         WARN_ON(rc);
 
         /* PS0 */
-        kvm_cvt_df(&fpr[reg_in1], &ps0_in1, &vcpu->arch.fpscr);
+        kvm_cvt_df(&fpr[reg_in1], &ps0_in1);
 
         if (scalar & SCALAR_LOW)
                 ps0_in2 = qpr[reg_in2];
         else
-                kvm_cvt_df(&fpr[reg_in2], &ps0_in2, &vcpu->arch.fpscr);
+                kvm_cvt_df(&fpr[reg_in2], &ps0_in2);
 
         func(&vcpu->arch.fpscr, &ps0_out, &ps0_in1, &ps0_in2);
 
@@ -579,7 +579,7 @@ static int kvmppc_ps_two_in(struct kvm_vcpu *vcpu, bool rc,
                 dprintk(KERN_INFO "PS2 ps0 -> f(0x%x, 0x%x) = 0x%x\n",
                                   ps0_in1, ps0_in2, ps0_out);
 
-                kvm_cvt_fd(&ps0_out, &fpr[reg_out], &vcpu->arch.fpscr);
+                kvm_cvt_fd(&ps0_out, &fpr[reg_out]);
         }
 
         /* PS1 */
@@ -615,13 +615,13 @@ static int kvmppc_ps_one_in(struct kvm_vcpu *vcpu, bool rc,
         WARN_ON(rc);
 
         /* PS0 */
-        kvm_cvt_df(&fpr[reg_in], &ps0_in, &vcpu->arch.fpscr);
+        kvm_cvt_df(&fpr[reg_in], &ps0_in);
         func(&vcpu->arch.fpscr, &ps0_out, &ps0_in);
 
         dprintk(KERN_INFO "PS1 ps0 -> f(0x%x) = 0x%x\n",
                           ps0_in, ps0_out);
 
-        kvm_cvt_fd(&ps0_out, &fpr[reg_out], &vcpu->arch.fpscr);
+        kvm_cvt_fd(&ps0_out, &fpr[reg_out]);
 
         /* PS1 */
         ps1_in = qpr[reg_in];
@@ -671,7 +671,7 @@ int kvmppc_emulate_paired_single(struct kvm_run *run, struct kvm_vcpu *vcpu)
 #ifdef DEBUG
         for (i = 0; i < ARRAY_SIZE(vcpu->arch.fpr); i++) {
                 u32 f;
-                kvm_cvt_df(&vcpu->arch.fpr[i], &f, &vcpu->arch.fpscr);
+                kvm_cvt_df(&vcpu->arch.fpr[i], &f);
                 dprintk(KERN_INFO "FPR[%d] = 0x%x / 0x%llx    QPR[%d] = 0x%x\n",
                         i, f, vcpu->arch.fpr[i], i, vcpu->arch.qpr[i]);
         }
@@ -796,8 +796,7 @@ int kvmppc_emulate_paired_single(struct kvm_run *run, struct kvm_vcpu *vcpu)
                         vcpu->arch.fpr[ax_rd] = vcpu->arch.fpr[ax_ra];
                         /* vcpu->arch.qpr[ax_rd] = vcpu->arch.fpr[ax_rb]; */
                         kvm_cvt_df(&vcpu->arch.fpr[ax_rb],
-                                   &vcpu->arch.qpr[ax_rd],
-                                   &vcpu->arch.fpscr);
+                                   &vcpu->arch.qpr[ax_rd]);
                         break;
                 case OP_4X_PS_MERGE01:
                         WARN_ON(rcomp);
@@ -808,19 +807,16 @@ int kvmppc_emulate_paired_single(struct kvm_run *run, struct kvm_vcpu *vcpu)
                         WARN_ON(rcomp);
                         /* vcpu->arch.fpr[ax_rd] = vcpu->arch.qpr[ax_ra]; */
                         kvm_cvt_fd(&vcpu->arch.qpr[ax_ra],
-                                   &vcpu->arch.fpr[ax_rd],
-                                   &vcpu->arch.fpscr);
+                                   &vcpu->arch.fpr[ax_rd]);
                         /* vcpu->arch.qpr[ax_rd] = vcpu->arch.fpr[ax_rb]; */
                         kvm_cvt_df(&vcpu->arch.fpr[ax_rb],
-                                   &vcpu->arch.qpr[ax_rd],
-                                   &vcpu->arch.fpscr);
+                                   &vcpu->arch.qpr[ax_rd]);
                         break;
                 case OP_4X_PS_MERGE11:
                         WARN_ON(rcomp);
                         /* vcpu->arch.fpr[ax_rd] = vcpu->arch.qpr[ax_ra]; */
                         kvm_cvt_fd(&vcpu->arch.qpr[ax_ra],
-                                   &vcpu->arch.fpr[ax_rd],
-                                   &vcpu->arch.fpscr);
+                                   &vcpu->arch.fpr[ax_rd]);
                         vcpu->arch.qpr[ax_rd] = vcpu->arch.qpr[ax_rb];
                         break;
                 }
@@ -1255,7 +1251,7 @@ int kvmppc_emulate_paired_single(struct kvm_run *run, struct kvm_vcpu *vcpu)
 #ifdef DEBUG
         for (i = 0; i < ARRAY_SIZE(vcpu->arch.fpr); i++) {
                 u32 f;
-                kvm_cvt_df(&vcpu->arch.fpr[i], &f, &vcpu->arch.fpscr);
+                kvm_cvt_df(&vcpu->arch.fpr[i], &f);
                 dprintk(KERN_INFO "FPR[%d] = 0x%x\n", i, f);
         }
 #endif
diff --git a/arch/powerpc/kvm/fpu.S b/arch/powerpc/kvm/fpu.S
index cb34bbe16113..bf68d597549e 100644
--- a/arch/powerpc/kvm/fpu.S
+++ b/arch/powerpc/kvm/fpu.S
@@ -273,19 +273,11 @@ FPD_THREE_IN(fnmsub)
 FPD_THREE_IN(fnmadd)
 
 _GLOBAL(kvm_cvt_fd)
-        lfd     0,0(r5)                 /* load up fpscr value */
-        MTFSF_L(0)
         lfs     0,0(r3)
         stfd    0,0(r4)
-        mffs    0
-        stfd    0,0(r5)                 /* save new fpscr value */
         blr
 
 _GLOBAL(kvm_cvt_df)
-        lfd     0,0(r5)                 /* load up fpscr value */
-        MTFSF_L(0)
         lfd     0,0(r3)
         stfs    0,0(r4)
-        mffs    0
-        stfd    0,0(r5)                 /* save new fpscr value */
         blr