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-rw-r--r--arch/ppc64/kernel/misc.S98
1 files changed, 98 insertions, 0 deletions
diff --git a/arch/ppc64/kernel/misc.S b/arch/ppc64/kernel/misc.S
index a05b50b738e..474df0a862b 100644
--- a/arch/ppc64/kernel/misc.S
+++ b/arch/ppc64/kernel/misc.S
@@ -680,6 +680,104 @@ _GLOBAL(kernel_thread)
ld r30,-16(r1)
blr
+/*
+ * disable_kernel_fp()
+ * Disable the FPU.
+ */
+_GLOBAL(disable_kernel_fp)
+ mfmsr r3
+ rldicl r0,r3,(63-MSR_FP_LG),1
+ rldicl r3,r0,(MSR_FP_LG+1),0
+ mtmsrd r3 /* disable use of fpu now */
+ isync
+ blr
+
+/*
+ * giveup_fpu(tsk)
+ * Disable FP for the task given as the argument,
+ * and save the floating-point registers in its thread_struct.
+ * Enables the FPU for use in the kernel on return.
+ */
+_GLOBAL(giveup_fpu)
+ mfmsr r5
+ ori r5,r5,MSR_FP
+ mtmsrd r5 /* enable use of fpu now */
+ isync
+ cmpdi 0,r3,0
+ beqlr- /* if no previous owner, done */
+ addi r3,r3,THREAD /* want THREAD of task */
+ ld r5,PT_REGS(r3)
+ cmpdi 0,r5,0
+ SAVE_32FPRS(0, r3)
+ mffs fr0
+ stfd fr0,THREAD_FPSCR(r3)
+ beq 1f
+ ld r4,_MSR-STACK_FRAME_OVERHEAD(r5)
+ li r3,MSR_FP|MSR_FE0|MSR_FE1
+ andc r4,r4,r3 /* disable FP for previous task */
+ std r4,_MSR-STACK_FRAME_OVERHEAD(r5)
+1:
+#ifndef CONFIG_SMP
+ li r5,0
+ ld r4,last_task_used_math@got(r2)
+ std r5,0(r4)
+#endif /* CONFIG_SMP */
+ blr
+
+#ifdef CONFIG_ALTIVEC
+
+#if 0 /* this has no callers for now */
+/*
+ * disable_kernel_altivec()
+ * Disable the VMX.
+ */
+_GLOBAL(disable_kernel_altivec)
+ mfmsr r3
+ rldicl r0,r3,(63-MSR_VEC_LG),1
+ rldicl r3,r0,(MSR_VEC_LG+1),0
+ mtmsrd r3 /* disable use of VMX now */
+ isync
+ blr
+#endif /* 0 */
+
+/*
+ * giveup_altivec(tsk)
+ * Disable VMX for the task given as the argument,
+ * and save the vector registers in its thread_struct.
+ * Enables the VMX for use in the kernel on return.
+ */
+_GLOBAL(giveup_altivec)
+ mfmsr r5
+ oris r5,r5,MSR_VEC@h
+ mtmsrd r5 /* enable use of VMX now */
+ isync
+ cmpdi 0,r3,0
+ beqlr- /* if no previous owner, done */
+ addi r3,r3,THREAD /* want THREAD of task */
+ ld r5,PT_REGS(r3)
+ cmpdi 0,r5,0
+ SAVE_32VRS(0,r4,r3)
+ mfvscr vr0
+ li r4,THREAD_VSCR
+ stvx vr0,r4,r3
+ beq 1f
+ ld r4,_MSR-STACK_FRAME_OVERHEAD(r5)
+ lis r3,MSR_VEC@h
+ andc r4,r4,r3 /* disable FP for previous task */
+ std r4,_MSR-STACK_FRAME_OVERHEAD(r5)
+1:
+#ifndef CONFIG_SMP
+ li r5,0
+ ld r4,last_task_used_altivec@got(r2)
+ std r5,0(r4)
+#endif /* CONFIG_SMP */
+ blr
+
+#endif /* CONFIG_ALTIVEC */
+
+_GLOBAL(__setup_cpu_power3)
+ blr
+
/* kexec_wait(phys_cpu)
*
* wait for the flag to change, indicating this kernel is going away but