[rtems commit] sparc: Remove superfluous FP enable

[Sebastian Huber]

Module:    rtems
Branch:    master
Commit:    1f6cdba6e1b13b05fec969938db46e08f4e68ace
Changeset: http://git.rtems.org/rtems/commit/?id=1f6cdba6e1b13b05fec969938db46e08f4e68ace

Author:    Sebastian Huber <sebastian.huber at embedded-brains.de>
Date:      Fri May 29 15:54:29 2015 +0200

sparc: Remove superfluous FP enable

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 f96d1ea..e967bf2 100644
--- a/cpukit/score/cpu/sparc/cpu.c
+++ b/cpukit/score/cpu/sparc/cpu.c
@@ -125,6 +125,11 @@ 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