[PATCH] powerpc/32: Remove unneccessary calculations in load_up_{fpu/altivec}

From: Christophe Leroy
Date: Wed Aug 18 2021 - 04:47:35 EST


No need to re-read SPRN_THREAD, we can calculate thread address
from current (r2).

And remove a reload of value 1 into r4 as r4 is already 1.

Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
---
arch/powerpc/kernel/fpu.S | 3 +--
arch/powerpc/kernel/vector.S | 4 +---
2 files changed, 2 insertions(+), 5 deletions(-)

diff --git a/arch/powerpc/kernel/fpu.S b/arch/powerpc/kernel/fpu.S
index 6010adcee16e..ba4afe3b5a9c 100644
--- a/arch/powerpc/kernel/fpu.S
+++ b/arch/powerpc/kernel/fpu.S
@@ -91,8 +91,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_VSX)
isync
/* enable use of FP after return */
#ifdef CONFIG_PPC32
- mfspr r5,SPRN_SPRG_THREAD /* current task's THREAD (phys) */
- tovirt(r5, r5)
+ addi r5,r2,THREAD
lwz r4,THREAD_FPEXC_MODE(r5)
ori r9,r9,MSR_FP /* enable FP for current */
or r9,r9,r4
diff --git a/arch/powerpc/kernel/vector.S b/arch/powerpc/kernel/vector.S
index fc120fac1910..ba03eedfdcd8 100644
--- a/arch/powerpc/kernel/vector.S
+++ b/arch/powerpc/kernel/vector.S
@@ -65,9 +65,8 @@ _GLOBAL(load_up_altivec)
1:
/* enable use of VMX after return */
#ifdef CONFIG_PPC32
- mfspr r5,SPRN_SPRG_THREAD /* current task's THREAD (phys) */
+ addi r5,r2,THREAD
oris r9,r9,MSR_VEC@h
- tovirt(r5, r5)
#else
ld r4,PACACURRENT(r13)
addi r5,r4,THREAD /* Get THREAD */
@@ -81,7 +80,6 @@ _GLOBAL(load_up_altivec)
li r4,1
stb r4,THREAD_LOAD_VEC(r5)
addi r6,r5,THREAD_VRSTATE
- li r4,1
li r10,VRSTATE_VSCR
stw r4,THREAD_USED_VR(r5)
lvx v0,r10,r6
--
2.25.0