[PATCH v5 16/27] arm64: daifflags: Include PMR in daifflags restore operations

From: Julien Thierry
Date: Tue Aug 28 2018 - 11:52:29 EST


The addition of PMR should not bypass the semantics of daifflags.

When DA_F are set, I bit is also set as no interrupts (even of higher
priority) is allowed.

When DA_F are cleared, I bit is cleared and interrupt enabling/disabling
goes through ICC_PMR_EL1.

Signed-off-by: Julien Thierry <julien.thierry@xxxxxxx>
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: Will Deacon <will.deacon@xxxxxxx>
Cc: James Morse <james.morse@xxxxxxx>
---
arch/arm64/include/asm/daifflags.h | 14 ++++++++++++--
1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/include/asm/daifflags.h b/arch/arm64/include/asm/daifflags.h
index 8d91f22..ccd95e8 100644
--- a/arch/arm64/include/asm/daifflags.h
+++ b/arch/arm64/include/asm/daifflags.h
@@ -18,8 +18,14 @@

#include <linux/irqflags.h>

-#define DAIF_PROCCTX 0
-#define DAIF_PROCCTX_NOIRQ PSR_I_BIT
+#include <asm/arch_gicv3.h>
+
+#define DAIF_PROCCTX MAKE_ARCH_FLAGS(0, ICC_PMR_EL1_UNMASKED)
+
+#define DAIF_PROCCTX_NOIRQ \
+ (gic_prio_masking_enabled() ? \
+ MAKE_ARCH_FLAGS(0, ICC_PMR_EL1_MASKED) : \
+ MAKE_ARCH_FLAGS(PSR_I_BIT, ICC_PMR_EL1_UNMASKED))

/* mask/save/unmask/restore all exceptions, including interrupts. */
static inline void local_daif_mask(void)
@@ -51,6 +57,10 @@ static inline void local_daif_unmask(void)
:
:
: "memory");
+
+ /* Unmask IRQs in PMR if needed */
+ if (gic_prio_masking_enabled())
+ arch_local_irq_enable();
}

static inline void local_daif_restore(unsigned long flags)
--
1.9.1