summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--arch/arm64/include/asm/barrier.h12
-rw-r--r--arch/arm64/include/asm/daifflags.h3
-rw-r--r--arch/arm64/include/asm/irqflags.h19
-rw-r--r--arch/arm64/include/asm/kvm_host.h3
-rw-r--r--arch/arm64/kernel/entry.S6
-rw-r--r--arch/arm64/kvm/hyp/switch.c4
-rw-r--r--drivers/irqchip/irq-gic-v3.c20
-rw-r--r--include/linux/irqchip/arm-gic-v3.h2
8 files changed, 53 insertions, 16 deletions
diff --git a/arch/arm64/include/asm/barrier.h b/arch/arm64/include/asm/barrier.h
index e0e2b1946f42..7d9cc5ec4971 100644
--- a/arch/arm64/include/asm/barrier.h
+++ b/arch/arm64/include/asm/barrier.h
@@ -29,6 +29,18 @@
SB_BARRIER_INSN"nop\n", \
ARM64_HAS_SB))
+#ifdef CONFIG_ARM64_PSEUDO_NMI
+#define pmr_sync() \
+ do { \
+ extern struct static_key_false gic_pmr_sync; \
+ \
+ if (static_branch_unlikely(&gic_pmr_sync)) \
+ dsb(sy); \
+ } while(0)
+#else
+#define pmr_sync() do {} while (0)
+#endif
+
#define mb() dsb(sy)
#define rmb() dsb(ld)
#define wmb() dsb(st)
diff --git a/arch/arm64/include/asm/daifflags.h b/arch/arm64/include/asm/daifflags.h
index 063c964af705..53cd5fab79a8 100644
--- a/arch/arm64/include/asm/daifflags.h
+++ b/arch/arm64/include/asm/daifflags.h
@@ -8,6 +8,7 @@
#include <linux/irqflags.h>
#include <asm/arch_gicv3.h>
+#include <asm/barrier.h>
#include <asm/cpufeature.h>
#define DAIF_PROCCTX 0
@@ -65,7 +66,7 @@ static inline void local_daif_restore(unsigned long flags)
if (system_uses_irq_prio_masking()) {
gic_write_pmr(GIC_PRIO_IRQON);
- dsb(sy);
+ pmr_sync();
}
} else if (system_uses_irq_prio_masking()) {
u64 pmr;
diff --git a/arch/arm64/include/asm/irqflags.h b/arch/arm64/include/asm/irqflags.h
index 1a59f0ed1ae3..aa4b6521ef14 100644
--- a/arch/arm64/include/asm/irqflags.h
+++ b/arch/arm64/include/asm/irqflags.h
@@ -6,6 +6,7 @@
#define __ASM_IRQFLAGS_H
#include <asm/alternative.h>
+#include <asm/barrier.h>
#include <asm/ptrace.h>
#include <asm/sysreg.h>
@@ -34,14 +35,14 @@ static inline void arch_local_irq_enable(void)
}
asm volatile(ALTERNATIVE(
- "msr daifclr, #2 // arch_local_irq_enable\n"
- "nop",
- __msr_s(SYS_ICC_PMR_EL1, "%0")
- "dsb sy",
+ "msr daifclr, #2 // arch_local_irq_enable",
+ __msr_s(SYS_ICC_PMR_EL1, "%0"),
ARM64_HAS_IRQ_PRIO_MASKING)
:
: "r" ((unsigned long) GIC_PRIO_IRQON)
: "memory");
+
+ pmr_sync();
}
static inline void arch_local_irq_disable(void)
@@ -116,14 +117,14 @@ static inline unsigned long arch_local_irq_save(void)
static inline void arch_local_irq_restore(unsigned long flags)
{
asm volatile(ALTERNATIVE(
- "msr daif, %0\n"
- "nop",
- __msr_s(SYS_ICC_PMR_EL1, "%0")
- "dsb sy",
- ARM64_HAS_IRQ_PRIO_MASKING)
+ "msr daif, %0",
+ __msr_s(SYS_ICC_PMR_EL1, "%0"),
+ ARM64_HAS_IRQ_PRIO_MASKING)
:
: "r" (flags)
: "memory");
+
+ pmr_sync();
}
#endif /* __ASM_IRQFLAGS_H */
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index f656169db8c3..5ecb091c8576 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -600,8 +600,7 @@ static inline void kvm_arm_vhe_guest_enter(void)
* local_daif_mask() already sets GIC_PRIO_PSR_I_SET, we just need a
* dsb to ensure the redistributor is forwards EL2 IRQs to the CPU.
*/
- if (system_uses_irq_prio_masking())
- dsb(sy);
+ pmr_sync();
}
static inline void kvm_arm_vhe_guest_exit(void)
diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S
index e304fe04b098..0a44f21bf087 100644
--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -269,8 +269,10 @@ alternative_else_nop_endif
alternative_if ARM64_HAS_IRQ_PRIO_MASKING
ldr x20, [sp, #S_PMR_SAVE]
msr_s SYS_ICC_PMR_EL1, x20
- /* Ensure priority change is seen by redistributor */
- dsb sy
+ mrs_s x21, SYS_ICC_CTLR_EL1
+ tbz x21, #6, .L__skip_pmr_sync\@ // Check for ICC_CTLR_EL1.PMHE
+ dsb sy // Ensure priority change is seen by redistributor
+.L__skip_pmr_sync\@:
alternative_else_nop_endif
ldp x21, x22, [sp, #S_PC] // load ELR, SPSR
diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c
index 3d3815020e36..402f18664f25 100644
--- a/arch/arm64/kvm/hyp/switch.c
+++ b/arch/arm64/kvm/hyp/switch.c
@@ -12,7 +12,7 @@
#include <kvm/arm_psci.h>
-#include <asm/arch_gicv3.h>
+#include <asm/barrier.h>
#include <asm/cpufeature.h>
#include <asm/kprobes.h>
#include <asm/kvm_asm.h>
@@ -592,7 +592,7 @@ int __hyp_text __kvm_vcpu_run_nvhe(struct kvm_vcpu *vcpu)
*/
if (system_uses_irq_prio_masking()) {
gic_write_pmr(GIC_PRIO_IRQON | GIC_PRIO_PSR_I_SET);
- dsb(sy);
+ pmr_sync();
}
vcpu = kern_hyp_va(vcpu);
diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c
index 422664ac5f53..0abc5a13adaa 100644
--- a/drivers/irqchip/irq-gic-v3.c
+++ b/drivers/irqchip/irq-gic-v3.c
@@ -87,6 +87,15 @@ static DEFINE_STATIC_KEY_TRUE(supports_deactivate_key);
*/
static DEFINE_STATIC_KEY_FALSE(supports_pseudo_nmis);
+/*
+ * Global static key controlling whether an update to PMR allowing more
+ * interrupts requires to be propagated to the redistributor (DSB SY).
+ * And this needs to be exported for modules to be able to enable
+ * interrupts...
+ */
+DEFINE_STATIC_KEY_FALSE(gic_pmr_sync);
+EXPORT_SYMBOL(gic_pmr_sync);
+
/* ppi_nmi_refs[n] == number of cpus having ppi[n + 16] set as NMI */
static refcount_t *ppi_nmi_refs;
@@ -1502,6 +1511,17 @@ static void gic_enable_nmi_support(void)
for (i = 0; i < gic_data.ppi_nr; i++)
refcount_set(&ppi_nmi_refs[i], 0);
+ /*
+ * Linux itself doesn't use 1:N distribution, so has no need to
+ * set PMHE. The only reason to have it set is if EL3 requires it
+ * (and we can't change it).
+ */
+ if (gic_read_ctlr() & ICC_CTLR_EL1_PMHE_MASK)
+ static_branch_enable(&gic_pmr_sync);
+
+ pr_info("%s ICC_PMR_EL1 synchronisation\n",
+ static_branch_unlikely(&gic_pmr_sync) ? "Forcing" : "Relaxing");
+
static_branch_enable(&supports_pseudo_nmis);
if (static_branch_likely(&supports_deactivate_key))
diff --git a/include/linux/irqchip/arm-gic-v3.h b/include/linux/irqchip/arm-gic-v3.h
index 5cc10cf7cb3e..a0bde9e12efa 100644
--- a/include/linux/irqchip/arm-gic-v3.h
+++ b/include/linux/irqchip/arm-gic-v3.h
@@ -487,6 +487,8 @@
#define ICC_CTLR_EL1_EOImode_MASK (1 << ICC_CTLR_EL1_EOImode_SHIFT)
#define ICC_CTLR_EL1_CBPR_SHIFT 0
#define ICC_CTLR_EL1_CBPR_MASK (1 << ICC_CTLR_EL1_CBPR_SHIFT)
+#define ICC_CTLR_EL1_PMHE_SHIFT 6
+#define ICC_CTLR_EL1_PMHE_MASK (1 << ICC_CTLR_EL1_PMHE_SHIFT)
#define ICC_CTLR_EL1_PRI_BITS_SHIFT 8
#define ICC_CTLR_EL1_PRI_BITS_MASK (0x7 << ICC_CTLR_EL1_PRI_BITS_SHIFT)
#define ICC_CTLR_EL1_ID_BITS_SHIFT 11