[PATCH 3/4] sparc: Remove superfluous FP enable
Sebastian Huber
sebastian.huber at embedded-brains.de
Fri May 29 13:54:29 UTC 2015
The FP context save/restore makes only sense in the context of FP
threads.
Update #2270.
---
cpukit/score/cpu/sparc/cpu.c | 5 +++++
cpukit/score/cpu/sparc/cpu_asm.S | 24 ++----------------------
2 files changed, 7 insertions(+), 22 deletions(-)
diff --git a/cpukit/score/cpu/sparc/cpu.c b/cpukit/score/cpu/sparc/cpu.c
index ee64b1e..bab0040 100644
--- a/cpukit/score/cpu/sparc/cpu.c
+++ b/cpukit/score/cpu/sparc/cpu.c
@@ -133,6 +133,11 @@ void _CPU_Initialize(void)
{
#if (SPARC_HAS_FPU == 1)
Context_Control_fp *pointer;
+ uint32_t psr;
+
+ sparc_get_psr( psr );
+ psr |= SPARC_PSR_EF_MASK;
+ sparc_set_psr( psr );
/*
* This seems to be the most appropriate way to obtain an initial
diff --git a/cpukit/score/cpu/sparc/cpu_asm.S b/cpukit/score/cpu/sparc/cpu_asm.S
index ddb2a13..3fa0532 100644
--- a/cpukit/score/cpu/sparc/cpu_asm.S
+++ b/cpukit/score/cpu/sparc/cpu_asm.S
@@ -44,17 +44,7 @@
.align 4
PUBLIC(_CPU_Context_save_fp)
SYM(_CPU_Context_save_fp):
- /*
- * The following enables the floating point unit.
- */
-
- mov %psr, %o1
- sethi %hi(SPARC_PSR_EF_MASK), %o2
- or %o2, %lo(SPARC_PSR_EF_MASK), %o2
- or %o1, %o2, %o1
- mov %o1, %psr ! **** ENABLE FLOAT ACCESS ****
- nop; nop; nop; ! Need three nops before EF is
- ld [%o0], %o1 ! active due to pipeline delay!!!
+ ld [%o0], %o1
std %f0, [%o1 + FO_F1_OFFSET]
std %f2, [%o1 + F2_F3_OFFSET]
std %f4, [%o1 + F4_F5_OFFSET]
@@ -90,17 +80,7 @@ SYM(_CPU_Context_save_fp):
.align 4
PUBLIC(_CPU_Context_restore_fp)
SYM(_CPU_Context_restore_fp):
- /*
- * The following enables the floating point unit.
- */
-
- mov %psr, %o1
- sethi %hi(SPARC_PSR_EF_MASK), %o2
- or %o2, %lo(SPARC_PSR_EF_MASK), %o2
- or %o1, %o2, %o1
- mov %o1, %psr ! **** ENABLE FLOAT ACCESS ****
- nop; nop; nop; ! Need three nops before EF is
- ld [%o0], %o1 ! active due to pipeline delay!!!
+ ld [%o0], %o1
ldd [%o1 + FO_F1_OFFSET], %f0
ldd [%o1 + F2_F3_OFFSET], %f2
ldd [%o1 + F4_F5_OFFSET], %f4
--
1.8.4.5
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