diff options
Diffstat (limited to 'arch/powerpc/kernel/process.c')
| -rw-r--r-- | arch/powerpc/kernel/process.c | 168 |
1 files changed, 151 insertions, 17 deletions
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c index 3c5736e52a14..612df305886b 100644 --- a/arch/powerpc/kernel/process.c +++ b/arch/powerpc/kernel/process.c @@ -133,6 +133,16 @@ void __msr_check_and_clear(unsigned long bits) EXPORT_SYMBOL(__msr_check_and_clear); #ifdef CONFIG_PPC_FPU +void __giveup_fpu(struct task_struct *tsk) +{ + save_fpu(tsk); + tsk->thread.regs->msr &= ~MSR_FP; +#ifdef CONFIG_VSX + if (cpu_has_feature(CPU_FTR_VSX)) + tsk->thread.regs->msr &= ~MSR_VSX; +#endif +} + void giveup_fpu(struct task_struct *tsk) { check_if_tm_restore_required(tsk); @@ -187,9 +197,32 @@ void enable_kernel_fp(void) } } EXPORT_SYMBOL(enable_kernel_fp); + +static int restore_fp(struct task_struct *tsk) { + if (tsk->thread.load_fp) { + load_fp_state(¤t->thread.fp_state); + current->thread.load_fp++; + return 1; + } + return 0; +} +#else +static int restore_fp(struct task_struct *tsk) { return 0; } #endif /* CONFIG_PPC_FPU */ #ifdef CONFIG_ALTIVEC +#define loadvec(thr) ((thr).load_vec) + +static void __giveup_altivec(struct task_struct *tsk) +{ + save_altivec(tsk); + tsk->thread.regs->msr &= ~MSR_VEC; +#ifdef CONFIG_VSX + if (cpu_has_feature(CPU_FTR_VSX)) + tsk->thread.regs->msr &= ~MSR_VSX; +#endif +} + void giveup_altivec(struct task_struct *tsk) { check_if_tm_restore_required(tsk); @@ -229,22 +262,49 @@ void flush_altivec_to_thread(struct task_struct *tsk) } } EXPORT_SYMBOL_GPL(flush_altivec_to_thread); + +static int restore_altivec(struct task_struct *tsk) +{ + if (cpu_has_feature(CPU_FTR_ALTIVEC) && tsk->thread.load_vec) { + load_vr_state(&tsk->thread.vr_state); + tsk->thread.used_vr = 1; + tsk->thread.load_vec++; + + return 1; + } + return 0; +} +#else +#define loadvec(thr) 0 +static inline int restore_altivec(struct task_struct *tsk) { return 0; } #endif /* CONFIG_ALTIVEC */ #ifdef CONFIG_VSX -void giveup_vsx(struct task_struct *tsk) +static void __giveup_vsx(struct task_struct *tsk) { - check_if_tm_restore_required(tsk); - - msr_check_and_set(MSR_FP|MSR_VEC|MSR_VSX); if (tsk->thread.regs->msr & MSR_FP) __giveup_fpu(tsk); if (tsk->thread.regs->msr & MSR_VEC) __giveup_altivec(tsk); + tsk->thread.regs->msr &= ~MSR_VSX; +} + +static void giveup_vsx(struct task_struct *tsk) +{ + check_if_tm_restore_required(tsk); + + msr_check_and_set(MSR_FP|MSR_VEC|MSR_VSX); __giveup_vsx(tsk); msr_check_and_clear(MSR_FP|MSR_VEC|MSR_VSX); } -EXPORT_SYMBOL(giveup_vsx); + +static void save_vsx(struct task_struct *tsk) +{ + if (tsk->thread.regs->msr & MSR_FP) + save_fpu(tsk); + if (tsk->thread.regs->msr & MSR_VEC) + save_altivec(tsk); +} void enable_kernel_vsx(void) { @@ -275,6 +335,19 @@ void flush_vsx_to_thread(struct task_struct *tsk) } } EXPORT_SYMBOL_GPL(flush_vsx_to_thread); + +static int restore_vsx(struct task_struct *tsk) +{ + if (cpu_has_feature(CPU_FTR_VSX)) { + tsk->thread.used_vsr = 1; + return 1; + } + + return 0; +} +#else +static inline int restore_vsx(struct task_struct *tsk) { return 0; } +static inline void save_vsx(struct task_struct *tsk) { } #endif /* CONFIG_VSX */ #ifdef CONFIG_SPE @@ -374,12 +447,76 @@ void giveup_all(struct task_struct *tsk) } EXPORT_SYMBOL(giveup_all); +void restore_math(struct pt_regs *regs) +{ + unsigned long msr; + + if (!current->thread.load_fp && !loadvec(current->thread)) + return; + + msr = regs->msr; + msr_check_and_set(msr_all_available); + + /* + * Only reload if the bit is not set in the user MSR, the bit BEING set + * indicates that the registers are hot + */ + if ((!(msr & MSR_FP)) && restore_fp(current)) + msr |= MSR_FP | current->thread.fpexc_mode; + + if ((!(msr & MSR_VEC)) && restore_altivec(current)) + msr |= MSR_VEC; + + if ((msr & (MSR_FP | MSR_VEC)) == (MSR_FP | MSR_VEC) && + restore_vsx(current)) { + msr |= MSR_VSX; + } + + msr_check_and_clear(msr_all_available); + + regs->msr = msr; +} + +void save_all(struct task_struct *tsk) +{ + unsigned long usermsr; + + if (!tsk->thread.regs) + return; + + usermsr = tsk->thread.regs->msr; + + if ((usermsr & msr_all_available) == 0) + return; + + msr_check_and_set(msr_all_available); + + /* + * Saving the way the register space is in hardware, save_vsx boils + * down to a save_fpu() and save_altivec() + */ + if (usermsr & MSR_VSX) { + save_vsx(tsk); + } else { + if (usermsr & MSR_FP) + save_fpu(tsk); + + if (usermsr & MSR_VEC) + save_altivec(tsk); + } + + if (usermsr & MSR_SPE) + __giveup_spe(tsk); + + msr_check_and_clear(msr_all_available); +} + void flush_all_to_thread(struct task_struct *tsk) { if (tsk->thread.regs) { preempt_disable(); BUG_ON(tsk != current); - giveup_all(tsk); + save_all(tsk); #ifdef CONFIG_SPE if (tsk->thread.regs->msr & MSR_SPE) @@ -832,17 +969,9 @@ void restore_tm_state(struct pt_regs *regs) msr_diff = current->thread.ckpt_regs.msr & ~regs->msr; msr_diff &= MSR_FP | MSR_VEC | MSR_VSX; - if (msr_diff & MSR_FP) { - msr_check_and_set(MSR_FP); - load_fp_state(¤t->thread.fp_state); - msr_check_and_clear(MSR_FP); - regs->msr |= current->thread.fpexc_mode; - } - if (msr_diff & MSR_VEC) { - msr_check_and_set(MSR_VEC); - load_vr_state(¤t->thread.vr_state); - msr_check_and_clear(MSR_VEC); - } + + restore_math(regs); + regs->msr |= msr_diff; } @@ -1006,6 +1135,10 @@ struct task_struct *__switch_to(struct task_struct *prev, batch = this_cpu_ptr(&ppc64_tlb_batch); batch->active = 1; } + + if (current_thread_info()->task->thread.regs) + restore_math(current_thread_info()->task->thread.regs); + #endif /* CONFIG_PPC_BOOK3S_64 */ return last; @@ -1307,6 +1440,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp, f = ret_from_fork; } + childregs->msr &= ~(MSR_FP|MSR_VEC|MSR_VSX); sp -= STACK_FRAME_OVERHEAD; /* |