[PATCH] powerpc: Fix handling of fpscr on 64-bit

[pandora-kernel.git] / arch / ppc64 / kernel / head.S

diff --git a/arch/ppc64/kernel/head.S b/arch/ppc64/kernel/head.S
index f58af9c..929f9f4 100644 (file)
--- a/arch/ppc64/kernel/head.S
+++ b/arch/ppc64/kernel/head.S
@@ -81,7 +81,7 @@ _stext:
 _GLOBAL(__start)
        /* NOP this out unconditionally */
 BEGIN_FTR_SECTION
-       b .__start_initialization_multiplatform
+       b       .__start_initialization_multiplatform
 END_FTR_SECTION(0, 1)
 #endif /* CONFIG_PPC_MULTIPLATFORM */
 
@@ -747,6 +747,7 @@ bad_stack:
  * any task or sent any task a signal, you should use
  * ret_from_except or ret_from_except_lite instead of this.
  */
+       .globl  fast_exception_return
 fast_exception_return:
        ld      r12,_MSR(r1)
        ld      r11,_NIP(r1)
@@ -858,62 +859,6 @@ fp_unavailable_common:
        bl      .kernel_fp_unavailable_exception
        BUG_OPCODE
 
-/*
- * load_up_fpu(unused, unused, tsk)
- * Disable FP for the task which had the FPU previously,
- * and save its floating-point registers in its thread_struct.
- * Enables the FPU for use in the kernel on return.
- * On SMP we know the fpu is free, since we give it up every
- * switch (ie, no lazy save of the FP registers).
- * On entry: r13 == 'current' && last_task_used_math != 'current'
- */
-_STATIC(load_up_fpu)
-       mfmsr   r5                      /* grab the current MSR */
-       ori     r5,r5,MSR_FP
-       mtmsrd  r5                      /* enable use of fpu now */
-       isync
-/*
- * For SMP, we don't do lazy FPU switching because it just gets too
- * horrendously complex, especially when a task switches from one CPU
- * to another.  Instead we call giveup_fpu in switch_to.
- *
- */
-#ifndef CONFIG_SMP
-       ld      r3,last_task_used_math@got(r2)
-       ld      r4,0(r3)
-       cmpdi   0,r4,0
-       beq     1f
-       /* Save FP state to last_task_used_math's THREAD struct */
-       addi    r4,r4,THREAD
-       SAVE_32FPRS(0, r4)
-       mffs    fr0
-       stfd    fr0,THREAD_FPSCR(r4)
-       /* Disable FP for last_task_used_math */
-       ld      r5,PT_REGS(r4)
-       ld      r4,_MSR-STACK_FRAME_OVERHEAD(r5)
-       li      r6,MSR_FP|MSR_FE0|MSR_FE1
-       andc    r4,r4,r6
-       std     r4,_MSR-STACK_FRAME_OVERHEAD(r5)
-1:
-#endif /* CONFIG_SMP */
-       /* enable use of FP after return */
-       ld      r4,PACACURRENT(r13)
-       addi    r5,r4,THREAD            /* Get THREAD */
-       ld      r4,THREAD_FPEXC_MODE(r5)
-       ori     r12,r12,MSR_FP
-       or      r12,r12,r4
-       std     r12,_MSR(r1)
-       lfd     fr0,THREAD_FPSCR(r5)
-       mtfsf   0xff,fr0
-       REST_32FPRS(0, r5)
-#ifndef CONFIG_SMP
-       /* Update last_task_used_math to 'current' */
-       subi    r4,r5,THREAD            /* Back to 'current' */
-       std     r4,0(r3)
-#endif /* CONFIG_SMP */
-       /* restore registers and return */
-       b       fast_exception_return
-
        .align  7
        .globl altivec_unavailable_common
 altivec_unavailable_common: