diff options
| -rw-r--r-- | arch/arm/include/asm/arch_gicv3.h | 7 | ||||
| -rw-r--r-- | arch/arm64/include/asm/arch_gicv3.h | 6 | ||||
| -rw-r--r-- | drivers/irqchip/irq-gic-v3.c | 43 |
3 files changed, 34 insertions, 22 deletions
diff --git a/arch/arm/include/asm/arch_gicv3.h b/arch/arm/include/asm/arch_gicv3.h index 413abfb42989..f82a819eb0db 100644 --- a/arch/arm/include/asm/arch_gicv3.h +++ b/arch/arm/include/asm/arch_gicv3.h @@ -48,6 +48,7 @@ static inline u32 read_ ## a64(void) \ return read_sysreg(a32); \ } \ +CPUIF_MAP(ICC_EOIR1, ICC_EOIR1_EL1) CPUIF_MAP(ICC_PMR, ICC_PMR_EL1) CPUIF_MAP(ICC_AP0R0, ICC_AP0R0_EL1) CPUIF_MAP(ICC_AP0R1, ICC_AP0R1_EL1) @@ -63,12 +64,6 @@ CPUIF_MAP(ICC_AP1R3, ICC_AP1R3_EL1) /* Low-level accessors */ -static inline void gic_write_eoir(u32 irq) -{ - write_sysreg(irq, ICC_EOIR1); - isb(); -} - static inline void gic_write_dir(u32 val) { write_sysreg(val, ICC_DIR); diff --git a/arch/arm64/include/asm/arch_gicv3.h b/arch/arm64/include/asm/arch_gicv3.h index 8bd5afc7b692..48d4473e8eee 100644 --- a/arch/arm64/include/asm/arch_gicv3.h +++ b/arch/arm64/include/asm/arch_gicv3.h @@ -26,12 +26,6 @@ * sets the GP register's most significant bits to 0 with an explicit cast. */ -static inline void gic_write_eoir(u32 irq) -{ - write_sysreg_s(irq, SYS_ICC_EOIR1_EL1); - isb(); -} - static __always_inline void gic_write_dir(u32 irq) { write_sysreg_s(irq, SYS_ICC_DIR_EL1); diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c index 7305d84f2df5..0cbc4e25c48d 100644 --- a/drivers/irqchip/irq-gic-v3.c +++ b/drivers/irqchip/irq-gic-v3.c @@ -556,7 +556,8 @@ static void gic_irq_nmi_teardown(struct irq_data *d) static void gic_eoi_irq(struct irq_data *d) { - gic_write_eoir(gic_irq(d)); + write_gicreg(gic_irq(d), ICC_EOIR1_EL1); + isb(); } static void gic_eoimode1_eoi_irq(struct irq_data *d) @@ -640,10 +641,38 @@ static void gic_deactivate_unhandled(u32 irqnr) if (irqnr < 8192) gic_write_dir(irqnr); } else { - gic_write_eoir(irqnr); + write_gicreg(irqnr, ICC_EOIR1_EL1); + isb(); } } +/* + * Follow a read of the IAR with any HW maintenance that needs to happen prior + * to invoking the relevant IRQ handler. We must do two things: + * + * (1) Ensure instruction ordering between a read of IAR and subsequent + * instructions in the IRQ handler using an ISB. + * + * It is possible for the IAR to report an IRQ which was signalled *after* + * the CPU took an IRQ exception as multiple interrupts can race to be + * recognized by the GIC, earlier interrupts could be withdrawn, and/or + * later interrupts could be prioritized by the GIC. + * + * For devices which are tightly coupled to the CPU, such as PMUs, a + * context synchronization event is necessary to ensure that system + * register state is not stale, as these may have been indirectly written + * *after* exception entry. + * + * (2) Deactivate the interrupt when EOI mode 1 is in use. + */ +static inline void gic_complete_ack(u32 irqnr) +{ + if (static_branch_likely(&supports_deactivate_key)) + write_gicreg(irqnr, ICC_EOIR1_EL1); + + isb(); +} + static inline void gic_handle_nmi(u32 irqnr, struct pt_regs *regs) { bool irqs_enabled = interrupts_enabled(regs); @@ -652,10 +681,7 @@ static inline void gic_handle_nmi(u32 irqnr, struct pt_regs *regs) if (irqs_enabled) nmi_enter(); - if (static_branch_likely(&supports_deactivate_key)) - gic_write_eoir(irqnr); - else - isb() + gic_complete_ack(irqnr); /* * Leave the PSR.I bit set to prevent other NMIs to be @@ -726,10 +752,7 @@ static asmlinkage void __exception_irq_entry gic_handle_irq(struct pt_regs *regs gic_arch_enable_irqs(); } - if (static_branch_likely(&supports_deactivate_key)) - gic_write_eoir(irqnr); - else - isb(); + gic_complete_ack(irqnr); if (generic_handle_domain_irq(gic_data.domain, irqnr)) { WARN_ONCE(true, "Unexpected interrupt received!\n"); |