Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 fixes from Catalin Marinas:
 "Mostly PMU fixes and a reworking of the pseudo-NMI disabling on broken
  MediaTek firmware:

   - Move the MediaTek GIC quirk handling from irqchip to core. Before
     the merging window commit 44bd78dd2b88 ("irqchip/gic-v3: Disable
     pseudo NMIs on MediaTek devices w/ firmware issues") temporarily
     addressed this issue. Fixed now at a deeper level in the arch code

   - Reject events meant for other PMUs in the CoreSight PMU driver,
     otherwise some of the core PMU events would disappear

   - Fix the Armv8 PMUv3 driver driver to not truncate 64-bit registers,
     causing some events to be invisible

   - Remove duplicate declaration of __arm64_sys##name following the
     patch to avoid prototype warning for syscalls

   - Typos in the elf_hwcap documentation"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64/syscall: Remove duplicate declaration
  Revert "arm64: smp: avoid NMI IPIs with broken MediaTek FW"
  arm64: Move MediaTek GIC quirk handling from irqchip to core
  arm64/arm: arm_pmuv3: perf: Don't truncate 64-bit registers
  perf: arm_cspmu: Reject events meant for other PMUs
  Documentation/arm64: Fix typos in elf_hwcaps

2 files changed, 39 insertions, 12 deletions

diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index f6b2e2906fc9..646591c67e7a 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -999,6 +999,37 @@ static void init_32bit_cpu_features(struct cpuinfo_32bit *info)
 	init_cpu_ftr_reg(SYS_MVFR2_EL1, info->reg_mvfr2);
 }
 
+#ifdef CONFIG_ARM64_PSEUDO_NMI
+static bool enable_pseudo_nmi;
+
+static int __init early_enable_pseudo_nmi(char *p)
+{
+	return kstrtobool(p, &enable_pseudo_nmi);
+}
+early_param("irqchip.gicv3_pseudo_nmi", early_enable_pseudo_nmi);
+
+static __init void detect_system_supports_pseudo_nmi(void)
+{
+	struct device_node *np;
+
+	if (!enable_pseudo_nmi)
+		return;
+
+	/*
+	 * Detect broken MediaTek firmware that doesn't properly save and
+	 * restore GIC priorities.
+	 */
+	np = of_find_compatible_node(NULL, NULL, "arm,gic-v3");
+	if (np && of_property_read_bool(np, "mediatek,broken-save-restore-fw")) {
+		pr_info("Pseudo-NMI disabled due to MediaTek Chromebook GICR save problem\n");
+		enable_pseudo_nmi = false;
+	}
+	of_node_put(np);
+}
+#else /* CONFIG_ARM64_PSEUDO_NMI */
+static inline void detect_system_supports_pseudo_nmi(void) { }
+#endif
+
 void __init init_cpu_features(struct cpuinfo_arm64 *info)
 {
 	/* Before we start using the tables, make sure it is sorted */
@@ -1058,6 +1089,13 @@ void __init init_cpu_features(struct cpuinfo_arm64 *info)
 	init_cpucap_indirect_list();
 
 	/*
+	 * Detect broken pseudo-NMI. Must be called _before_ the call to
+	 * setup_boot_cpu_capabilities() since it interacts with
+	 * can_use_gic_priorities().
+	 */
+	detect_system_supports_pseudo_nmi();
+
+	/*
 	 * Detect and enable early CPU capabilities based on the boot CPU,
 	 * after we have initialised the CPU feature infrastructure.
 	 */
@@ -2085,14 +2123,6 @@ static void cpu_enable_e0pd(struct arm64_cpu_capabilities const *cap)
 #endif /* CONFIG_ARM64_E0PD */
 
 #ifdef CONFIG_ARM64_PSEUDO_NMI
-static bool enable_pseudo_nmi;
-
-static int __init early_enable_pseudo_nmi(char *p)
-{
-	return kstrtobool(p, &enable_pseudo_nmi);
-}
-early_param("irqchip.gicv3_pseudo_nmi", early_enable_pseudo_nmi);
-
 static bool can_use_gic_priorities(const struct arm64_cpu_capabilities *entry,
 				   int scope)
 {
diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
index be95b523c101..defbab84e9e5 100644
--- a/arch/arm64/kernel/smp.c
+++ b/arch/arm64/kernel/smp.c
@@ -965,10 +965,7 @@ static void smp_cross_call(const struct cpumask *target, unsigned int ipinr)
 
 static bool ipi_should_be_nmi(enum ipi_msg_type ipi)
 {
-	DECLARE_STATIC_KEY_FALSE(supports_pseudo_nmis);
-
-	if (!system_uses_irq_prio_masking() ||
-	    !static_branch_likely(&supports_pseudo_nmis))
+	if (!system_uses_irq_prio_masking())
 		return false;
 
 	switch (ipi) {