1 files changed, 247 insertions, 87 deletions

diff --git a/arch/powerpc/include/asm/hw_irq.h b/arch/powerpc/include/asm/hw_irq.h
index e3a905e3d573..317659fdeacf 100644
--- a/arch/powerpc/include/asm/hw_irq.h
+++ b/arch/powerpc/include/asm/hw_irq.h
@@ -18,27 +18,39 @@
  * PACA flags in paca->irq_happened.
  *
  * This bits are set when interrupts occur while soft-disabled
- * and allow a proper replay. Additionally, PACA_IRQ_HARD_DIS
- * is set whenever we manually hard disable.
+ * and allow a proper replay.
+ *
+ * The PACA_IRQ_HARD_DIS is set whenever we hard disable. It is almost
+ * always in synch with the MSR[EE] state, except:
+ * - A window in interrupt entry, where hardware disables MSR[EE] and that
+ *   must be "reconciled" with the soft mask state.
+ * - NMI interrupts that hit in awkward places, until they fix the state.
+ * - When local irqs are being enabled and state is being fixed up.
+ * - When returning from an interrupt there are some windows where this
+ *   can become out of synch, but gets fixed before the RFI or before
+ *   executing the next user instruction (see arch/powerpc/kernel/interrupt.c).
  */
 #define PACA_IRQ_HARD_DIS	0x01
 #define PACA_IRQ_DBELL		0x02
 #define PACA_IRQ_EE		0x04
 #define PACA_IRQ_DEC		0x08 /* Or FIT */
-#define PACA_IRQ_EE_EDGE	0x10 /* BookE only */
-#define PACA_IRQ_HMI		0x20
-#define PACA_IRQ_PMI		0x40
+#define PACA_IRQ_HMI		0x10
+#define PACA_IRQ_PMI		0x20
+#define PACA_IRQ_REPLAYING	0x40
 
 /*
  * Some soft-masked interrupts must be hard masked until they are replayed
  * (e.g., because the soft-masked handler does not clear the exception).
+ * Interrupt replay itself must remain hard masked too.
  */
 #ifdef CONFIG_PPC_BOOK3S
-#define PACA_IRQ_MUST_HARD_MASK	(PACA_IRQ_EE|PACA_IRQ_PMI)
+#define PACA_IRQ_MUST_HARD_MASK	(PACA_IRQ_EE|PACA_IRQ_PMI|PACA_IRQ_REPLAYING)
 #else
-#define PACA_IRQ_MUST_HARD_MASK	(PACA_IRQ_EE)
+#define PACA_IRQ_MUST_HARD_MASK	(PACA_IRQ_EE|PACA_IRQ_REPLAYING)
 #endif
 
+#endif /* CONFIG_PPC64 */
+
 /*
  * flags for paca->irq_soft_mask
  */
@@ -47,18 +59,56 @@
 #define IRQS_PMI_DISABLED	2
 #define IRQS_ALL_DISABLED	(IRQS_DISABLED | IRQS_PMI_DISABLED)
 
-#endif /* CONFIG_PPC64 */
-
 #ifndef __ASSEMBLY__
 
-extern void replay_system_reset(void);
-extern void __replay_interrupt(unsigned int vector);
+static inline void __hard_irq_enable(void)
+{
+	if (IS_ENABLED(CONFIG_BOOKE_OR_40x))
+		wrtee(MSR_EE);
+	else if (IS_ENABLED(CONFIG_PPC_8xx))
+		wrtspr(SPRN_EIE);
+	else if (IS_ENABLED(CONFIG_PPC_BOOK3S_64))
+		__mtmsrd(MSR_EE | MSR_RI, 1);
+	else
+		mtmsr(mfmsr() | MSR_EE);
+}
 
-extern void timer_interrupt(struct pt_regs *);
-extern void timer_broadcast_interrupt(void);
-extern void performance_monitor_exception(struct pt_regs *regs);
-extern void WatchdogException(struct pt_regs *regs);
-extern void unknown_exception(struct pt_regs *regs);
+static inline void __hard_irq_disable(void)
+{
+	if (IS_ENABLED(CONFIG_BOOKE_OR_40x))
+		wrtee(0);
+	else if (IS_ENABLED(CONFIG_PPC_8xx))
+		wrtspr(SPRN_EID);
+	else if (IS_ENABLED(CONFIG_PPC_BOOK3S_64))
+		__mtmsrd(MSR_RI, 1);
+	else
+		mtmsr(mfmsr() & ~MSR_EE);
+}
+
+static inline void __hard_EE_RI_disable(void)
+{
+	if (IS_ENABLED(CONFIG_BOOKE_OR_40x))
+		wrtee(0);
+	else if (IS_ENABLED(CONFIG_PPC_8xx))
+		wrtspr(SPRN_NRI);
+	else if (IS_ENABLED(CONFIG_PPC_BOOK3S_64))
+		__mtmsrd(0, 1);
+	else
+		mtmsr(mfmsr() & ~(MSR_EE | MSR_RI));
+}
+
+static inline void __hard_RI_enable(void)
+{
+	if (IS_ENABLED(CONFIG_BOOKE_OR_40x))
+		return;
+
+	if (IS_ENABLED(CONFIG_PPC_8xx))
+		wrtspr(SPRN_EID);
+	else if (IS_ENABLED(CONFIG_PPC_BOOK3S_64))
+		__mtmsrd(MSR_RI, 1);
+	else
+		mtmsr(mfmsr() | MSR_RI);
+}
 
 #ifdef CONFIG_PPC64
 #include <asm/paca.h>
@@ -82,7 +132,6 @@ static inline notrace unsigned long irq_soft_mask_return(void)
  */
 static inline notrace void irq_soft_mask_set(unsigned long mask)
 {
-#ifdef CONFIG_PPC_IRQ_SOFT_MASK_DEBUG
 	/*
 	 * The irq mask must always include the STD bit if any are set.
 	 *
@@ -97,8 +146,8 @@ static inline notrace void irq_soft_mask_set(unsigned long mask)
 	 * unmasks to be replayed, among other things. For now, take
 	 * the simple approach.
 	 */
-	WARN_ON(mask && !(mask & IRQS_DISABLED));
-#endif
+	if (IS_ENABLED(CONFIG_PPC_IRQ_SOFT_MASK_DEBUG))
+		WARN_ON(mask && !(mask & IRQS_DISABLED));
 
 	asm volatile(
 		"stb %0,%1(13)"
@@ -110,36 +159,27 @@ static inline notrace void irq_soft_mask_set(unsigned long mask)
 
 static inline notrace unsigned long irq_soft_mask_set_return(unsigned long mask)
 {
-	unsigned long flags;
+	unsigned long flags = irq_soft_mask_return();
 
-#ifdef CONFIG_PPC_IRQ_SOFT_MASK_DEBUG
-	WARN_ON(mask && !(mask & IRQS_DISABLED));
-#endif
-
-	asm volatile(
-		"lbz %0,%1(13); stb %2,%1(13)"
-		: "=&r" (flags)
-		: "i" (offsetof(struct paca_struct, irq_soft_mask)),
-		  "r" (mask)
-		: "memory");
+	irq_soft_mask_set(mask);
 
 	return flags;
 }
 
 static inline notrace unsigned long irq_soft_mask_or_return(unsigned long mask)
 {
-	unsigned long flags, tmp;
+	unsigned long flags = irq_soft_mask_return();
 
-	asm volatile(
-		"lbz %0,%2(13); or %1,%0,%3; stb %1,%2(13)"
-		: "=&r" (flags), "=r" (tmp)
-		: "i" (offsetof(struct paca_struct, irq_soft_mask)),
-		  "r" (mask)
-		: "memory");
+	irq_soft_mask_set(flags | mask);
 
-#ifdef CONFIG_PPC_IRQ_SOFT_MASK_DEBUG
-	WARN_ON((mask | flags) && !((mask | flags) & IRQS_DISABLED));
-#endif
+	return flags;
+}
+
+static inline notrace unsigned long irq_soft_mask_andc_return(unsigned long mask)
+{
+	unsigned long flags = irq_soft_mask_return();
+
+	irq_soft_mask_set(flags & ~mask);
 
 	return flags;
 }
@@ -163,7 +203,7 @@ static inline void arch_local_irq_enable(void)
 
 static inline unsigned long arch_local_irq_save(void)
 {
-	return irq_soft_mask_set_return(IRQS_DISABLED);
+	return irq_soft_mask_or_return(IRQS_DISABLED);
 }
 
 static inline bool arch_irqs_disabled_flags(unsigned long flags)
@@ -176,6 +216,42 @@ static inline bool arch_irqs_disabled(void)
 	return arch_irqs_disabled_flags(arch_local_save_flags());
 }
 
+static inline void set_pmi_irq_pending(void)
+{
+	/*
+	 * Invoked from PMU callback functions to set PMI bit in the paca.
+	 * This has to be called with irq's disabled (via hard_irq_disable()).
+	 */
+	if (IS_ENABLED(CONFIG_PPC_IRQ_SOFT_MASK_DEBUG))
+		WARN_ON_ONCE(mfmsr() & MSR_EE);
+
+	get_paca()->irq_happened |= PACA_IRQ_PMI;
+}
+
+static inline void clear_pmi_irq_pending(void)
+{
+	/*
+	 * Invoked from PMU callback functions to clear the pending PMI bit
+	 * in the paca.
+	 */
+	if (IS_ENABLED(CONFIG_PPC_IRQ_SOFT_MASK_DEBUG))
+		WARN_ON_ONCE(mfmsr() & MSR_EE);
+
+	get_paca()->irq_happened &= ~PACA_IRQ_PMI;
+}
+
+static inline bool pmi_irq_pending(void)
+{
+	/*
+	 * Invoked from PMU callback functions to check if there is a pending
+	 * PMI bit in the paca.
+	 */
+	if (get_paca()->irq_happened & PACA_IRQ_PMI)
+		return true;
+
+	return false;
+}
+
 #ifdef CONFIG_PPC_BOOK3S
 /*
  * To support disabling and enabling of irq with PMI, set of
@@ -200,17 +276,14 @@ static inline bool arch_irqs_disabled(void)
 #define powerpc_local_irq_pmu_save(flags)			\
 	 do {							\
 		raw_local_irq_pmu_save(flags);			\
-		trace_hardirqs_off();				\
+		if (!raw_irqs_disabled_flags(flags))		\
+			trace_hardirqs_off();			\
 	} while(0)
 #define powerpc_local_irq_pmu_restore(flags)			\
 	do {							\
-		if (raw_irqs_disabled_flags(flags)) {		\
-			raw_local_irq_pmu_restore(flags);	\
-			trace_hardirqs_off();			\
-		} else {					\
+		if (!raw_irqs_disabled_flags(flags))		\
 			trace_hardirqs_on();			\
-			raw_local_irq_pmu_restore(flags);	\
-		}						\
+		raw_local_irq_pmu_restore(flags);		\
 	} while(0)
 #else
 #define powerpc_local_irq_pmu_save(flags)			\
@@ -225,44 +298,99 @@ static inline bool arch_irqs_disabled(void)
 
 #endif /* CONFIG_PPC_BOOK3S */
 
-#ifdef CONFIG_PPC_BOOK3E
-#define __hard_irq_enable()	wrtee(MSR_EE)
-#define __hard_irq_disable()	wrtee(0)
-#else
-#define __hard_irq_enable()	__mtmsrd(MSR_EE|MSR_RI, 1)
-#define __hard_irq_disable()	__mtmsrd(MSR_RI, 1)
-#endif
-
 #define hard_irq_disable()	do {					\
 	unsigned long flags;						\
 	__hard_irq_disable();						\
 	flags = irq_soft_mask_set_return(IRQS_ALL_DISABLED);		\
 	local_paca->irq_happened |= PACA_IRQ_HARD_DIS;			\
 	if (!arch_irqs_disabled_flags(flags)) {				\
-		asm ("stdx %%r1, 0, %1 ;"				\
-		     : "=m" (local_paca->saved_r1)			\
-		     : "b" (&local_paca->saved_r1));			\
+		asm volatile("std%X0 %1,%0" : "=m" (local_paca->saved_r1) \
+					    : "r" (current_stack_pointer)); \
 		trace_hardirqs_off();					\
 	}								\
 } while(0)
 
+static inline bool __lazy_irq_pending(u8 irq_happened)
+{
+	return !!(irq_happened & ~PACA_IRQ_HARD_DIS);
+}
+
+/*
+ * Check if a lazy IRQ is pending. Should be called with IRQs hard disabled.
+ */
 static inline bool lazy_irq_pending(void)
 {
-	return !!(get_paca()->irq_happened & ~PACA_IRQ_HARD_DIS);
+	return __lazy_irq_pending(get_paca()->irq_happened);
 }
 
 /*
- * This is called by asynchronous interrupts to conditionally
- * re-enable hard interrupts after having cleared the source
- * of the interrupt. They are kept disabled if there is a different
- * soft-masked interrupt pending that requires hard masking.
+ * Check if a lazy IRQ is pending, with no debugging checks.
+ * Should be called with IRQs hard disabled.
+ * For use in RI disabled code or other constrained situations.
  */
-static inline void may_hard_irq_enable(void)
+static inline bool lazy_irq_pending_nocheck(void)
 {
-	if (!(get_paca()->irq_happened & PACA_IRQ_MUST_HARD_MASK)) {
-		get_paca()->irq_happened &= ~PACA_IRQ_HARD_DIS;
-		__hard_irq_enable();
+	return __lazy_irq_pending(local_paca->irq_happened);
+}
+
+bool power_pmu_wants_prompt_pmi(void);
+
+/*
+ * This is called by asynchronous interrupts to check whether to
+ * conditionally re-enable hard interrupts after having cleared
+ * the source of the interrupt. They are kept disabled if there
+ * is a different soft-masked interrupt pending that requires hard
+ * masking.
+ */
+static inline bool should_hard_irq_enable(struct pt_regs *regs)
+{
+	if (IS_ENABLED(CONFIG_PPC_IRQ_SOFT_MASK_DEBUG)) {
+		WARN_ON(irq_soft_mask_return() != IRQS_ALL_DISABLED);
+		WARN_ON(!(get_paca()->irq_happened & PACA_IRQ_HARD_DIS));
+		WARN_ON(mfmsr() & MSR_EE);
 	}
+
+	if (!IS_ENABLED(CONFIG_PERF_EVENTS))
+		return false;
+	/*
+	 * If the PMU is not running, there is not much reason to enable
+	 * MSR[EE] in irq handlers because any interrupts would just be
+	 * soft-masked.
+	 *
+	 * TODO: Add test for 64e
+	 */
+	if (IS_ENABLED(CONFIG_PPC_BOOK3S_64)) {
+		if (!power_pmu_wants_prompt_pmi())
+			return false;
+		/*
+		 * If PMIs are disabled then IRQs should be disabled as well,
+		 * so we shouldn't see this condition, check for it just in
+		 * case because we are about to enable PMIs.
+		 */
+		if (WARN_ON_ONCE(regs->softe & IRQS_PMI_DISABLED))
+			return false;
+	}
+
+	if (get_paca()->irq_happened & PACA_IRQ_MUST_HARD_MASK)
+		return false;
+
+	return true;
+}
+
+/*
+ * Do the hard enabling, only call this if should_hard_irq_enable is true.
+ * This allows PMI interrupts to profile irq handlers.
+ */
+static inline void do_hard_irq_enable(void)
+{
+	/*
+	 * Asynch interrupts come in with IRQS_ALL_DISABLED,
+	 * PACA_IRQ_HARD_DIS, and MSR[EE]=0.
+	 */
+	if (IS_ENABLED(CONFIG_PPC_BOOK3S_64))
+		irq_soft_mask_andc_return(IRQS_PMI_DISABLED);
+	get_paca()->irq_happened &= ~PACA_IRQ_HARD_DIS;
+	__hard_irq_enable();
 }
 
 static inline bool arch_irq_disabled_regs(struct pt_regs *regs)
@@ -278,8 +406,17 @@ extern void irq_set_pending_from_srr1(unsigned long srr1);
 
 extern void force_external_irq_replay(void);
 
+static inline void irq_soft_mask_regs_set_state(struct pt_regs *regs, unsigned long val)
+{
+	regs->softe = val;
+}
 #else /* CONFIG_PPC64 */
 
+static inline notrace unsigned long irq_soft_mask_return(void)
+{
+	return 0;
+}
+
 static inline unsigned long arch_local_save_flags(void)
 {
 	return mfmsr();
@@ -309,22 +446,12 @@ static inline unsigned long arch_local_irq_save(void)
 
 static inline void arch_local_irq_disable(void)
 {
-	if (IS_ENABLED(CONFIG_BOOKE))
-		wrtee(0);
-	else if (IS_ENABLED(CONFIG_PPC_8xx))
-		wrtspr(SPRN_EID);
-	else
-		mtmsr(mfmsr() & ~MSR_EE);
+	__hard_irq_disable();
 }
 
 static inline void arch_local_irq_enable(void)
 {
-	if (IS_ENABLED(CONFIG_BOOKE))
-		wrtee(MSR_EE);
-	else if (IS_ENABLED(CONFIG_PPC_8xx))
-		wrtspr(SPRN_EIE);
-	else
-		mtmsr(mfmsr() | MSR_EE);
+	__hard_irq_enable();
 }
 
 static inline bool arch_irqs_disabled_flags(unsigned long flags)
@@ -344,17 +471,50 @@ static inline bool arch_irq_disabled_regs(struct pt_regs *regs)
 	return !(regs->msr & MSR_EE);
 }
 
-static inline void may_hard_irq_enable(void) { }
+static __always_inline bool should_hard_irq_enable(struct pt_regs *regs)
+{
+	return false;
+}
+
+static inline void do_hard_irq_enable(void)
+{
+	BUILD_BUG();
+}
+
+static inline void clear_pmi_irq_pending(void) { }
+static inline void set_pmi_irq_pending(void) { }
+static inline bool pmi_irq_pending(void) { return false; }
 
+static inline void irq_soft_mask_regs_set_state(struct pt_regs *regs, unsigned long val)
+{
+}
 #endif /* CONFIG_PPC64 */
 
-#define ARCH_IRQ_INIT_FLAGS	IRQ_NOREQUEST
+static inline unsigned long mtmsr_isync_irqsafe(unsigned long msr)
+{
+#ifdef CONFIG_PPC64
+	if (arch_irqs_disabled()) {
+		/*
+		 * With soft-masking, MSR[EE] can change from 1 to 0
+		 * asynchronously when irqs are disabled, and we don't want to
+		 * set MSR[EE] back to 1 here if that has happened. A race-free
+		 * way to do this is ensure EE is already 0. Another way it
+		 * could be done is with a RESTART_TABLE handler, but that's
+		 * probably overkill here.
+		 */
+		msr &= ~MSR_EE;
+		mtmsr_isync(msr);
+		irq_soft_mask_set(IRQS_ALL_DISABLED);
+		local_paca->irq_happened |= PACA_IRQ_HARD_DIS;
+	} else
+#endif
+		mtmsr_isync(msr);
 
-/*
- * interrupt-retrigger: should we handle this via lost interrupts and IPIs
- * or should we not care like we do now ? --BenH.
- */
-struct irq_chip;
+	return msr;
+}
+
+
+#define ARCH_IRQ_INIT_FLAGS	IRQ_NOREQUEST
 
 #endif  /* __ASSEMBLY__ */
 #endif	/* __KERNEL__ */