From 1a1ebd5fb1e203ee8cc73508cc7a38ac4b804596 Mon Sep 17 00:00:00 2001 From: Tirumalesh Chalamarla Date: Thu, 4 Feb 2016 10:45:25 -0800 Subject: [PATCH] irqchip/gic-v3: Make sure read from ICC_IAR1_EL1 is visible on redestributor The ARM GICv3 specification mentions the need for dsb after a read from the ICC_IAR1_EL1 register: 4.1.1 Physical CPU Interface: The effects of reading ICC_IAR0_EL1 and ICC_IAR1_EL1 on the state of a returned INTID are not guaranteed to be visible until after the execution of a DSB. Not having this could result in missed interrupts, so let's add the required barrier. [Marc: fixed commit message] Acked-by: Marc Zyngier Signed-off-by: Tirumalesh Chalamarla Signed-off-by: Marc Zyngier --- arch/arm64/include/asm/arch_gicv3.h | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/arm64/include/asm/arch_gicv3.h b/arch/arm64/include/asm/arch_gicv3.h index 2731d3b25ed2..8ec88e5b290f 100644 --- a/arch/arm64/include/asm/arch_gicv3.h +++ b/arch/arm64/include/asm/arch_gicv3.h @@ -103,6 +103,7 @@ static inline u64 gic_read_iar_common(void) u64 irqstat; asm volatile("mrs_s %0, " __stringify(ICC_IAR1_EL1) : "=r" (irqstat)); + dsb(sy); return irqstat; } -- 2.39.5