diff options
Diffstat (limited to 'arch/powerpc/kernel/irq.c')
| -rw-r--r-- | arch/powerpc/kernel/irq.c | 96 |
1 files changed, 96 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c index 72cb45393ef2..91e63eac4e8f 100644 --- a/arch/powerpc/kernel/irq.c +++ b/arch/powerpc/kernel/irq.c @@ -121,6 +121,7 @@ void replay_soft_interrupts(void) ppc_save_regs(®s); regs.softe = IRQS_ENABLED; + regs.msr |= MSR_EE; again: if (IS_ENABLED(CONFIG_PPC_IRQ_SOFT_MASK_DEBUG)) @@ -217,6 +218,100 @@ static inline void replay_soft_interrupts_irqrestore(void) #define replay_soft_interrupts_irqrestore() replay_soft_interrupts() #endif +#ifdef CONFIG_CC_HAS_ASM_GOTO +notrace void arch_local_irq_restore(unsigned long mask) +{ + unsigned char irq_happened; + + /* Write the new soft-enabled value if it is a disable */ + if (mask) { + irq_soft_mask_set(mask); + return; + } + + /* + * After the stb, interrupts are unmasked and there are no interrupts + * pending replay. The restart sequence makes this atomic with + * respect to soft-masked interrupts. If this was just a simple code + * sequence, a soft-masked interrupt could become pending right after + * the comparison and before the stb. + * + * This allows interrupts to be unmasked without hard disabling, and + * also without new hard interrupts coming in ahead of pending ones. + */ + asm_volatile_goto( +"1: \n" +" lbz 9,%0(13) \n" +" cmpwi 9,0 \n" +" bne %l[happened] \n" +" stb 9,%1(13) \n" +"2: \n" + RESTART_TABLE(1b, 2b, 1b) + : : "i" (offsetof(struct paca_struct, irq_happened)), + "i" (offsetof(struct paca_struct, irq_soft_mask)) + : "cr0", "r9" + : happened); + + if (IS_ENABLED(CONFIG_PPC_IRQ_SOFT_MASK_DEBUG)) + WARN_ON_ONCE(!(mfmsr() & MSR_EE)); + + return; + +happened: + irq_happened = get_irq_happened(); + if (IS_ENABLED(CONFIG_PPC_IRQ_SOFT_MASK_DEBUG)) + WARN_ON_ONCE(!irq_happened); + + if (irq_happened == PACA_IRQ_HARD_DIS) { + if (IS_ENABLED(CONFIG_PPC_IRQ_SOFT_MASK_DEBUG)) + WARN_ON_ONCE(mfmsr() & MSR_EE); + irq_soft_mask_set(IRQS_ENABLED); + local_paca->irq_happened = 0; + __hard_irq_enable(); + return; + } + + /* Have interrupts to replay, need to hard disable first */ + if (!(irq_happened & PACA_IRQ_HARD_DIS)) { + if (IS_ENABLED(CONFIG_PPC_IRQ_SOFT_MASK_DEBUG)) { + if (!(mfmsr() & MSR_EE)) { + /* + * An interrupt could have come in and cleared + * MSR[EE] and set IRQ_HARD_DIS, so check + * IRQ_HARD_DIS again and warn if it is still + * clear. + */ + irq_happened = get_irq_happened(); + WARN_ON_ONCE(!(irq_happened & PACA_IRQ_HARD_DIS)); + } + } + __hard_irq_disable(); + local_paca->irq_happened |= PACA_IRQ_HARD_DIS; + } else { + if (IS_ENABLED(CONFIG_PPC_IRQ_SOFT_MASK_DEBUG)) { + if (WARN_ON_ONCE(mfmsr() & MSR_EE)) + __hard_irq_disable(); + } + } + + /* + * Disable preempt here, so that the below preempt_enable will + * perform resched if required (a replayed interrupt may set + * need_resched). + */ + preempt_disable(); + irq_soft_mask_set(IRQS_ALL_DISABLED); + trace_hardirqs_off(); + + replay_soft_interrupts_irqrestore(); + local_paca->irq_happened = 0; + + trace_hardirqs_on(); + irq_soft_mask_set(IRQS_ENABLED); + __hard_irq_enable(); + preempt_enable(); +} +#else notrace void arch_local_irq_restore(unsigned long mask) { unsigned char irq_happened; @@ -288,6 +383,7 @@ notrace void arch_local_irq_restore(unsigned long mask) __hard_irq_enable(); preempt_enable(); } +#endif EXPORT_SYMBOL(arch_local_irq_restore); /* |