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

Pull arm64 fixes from Will Deacon:
 "A typo fix for a PMU driver, a workround for a side-channel erratum on
  Cortex-A520 and a fix for the local timer save/restore when using ACPI
  with Qualcomm's custom CPUs:

   - Workaround for Cortex-A520 erratum #2966298

   - Fix typo in Arm CMN PMU driver that breaks counter overflow handling

   - Fix timer handling across idle for Qualcomm custom CPUs"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  cpuidle, ACPI: Evaluate LPI arch_flags for broadcast timer
  arm64: errata: Add Cortex-A520 speculative unprivileged load workaround
  arm64: Add Cortex-A520 CPU part definition
  perf/arm-cmn: Fix the unhandled overflow status of counter 4 to 7

6 files changed, 47 insertions, 0 deletions

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index b10515c0200b..78f20e632712 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -1037,6 +1037,19 @@ config ARM64_ERRATUM_2645198
 
 	  If unsure, say Y.
 
+config ARM64_ERRATUM_2966298
+	bool "Cortex-A520: 2966298: workaround for speculatively executed unprivileged load"
+	default y
+	help
+	  This option adds the workaround for ARM Cortex-A520 erratum 2966298.
+
+	  On an affected Cortex-A520 core, a speculatively executed unprivileged
+	  load might leak data from a privileged level via a cache side channel.
+
+	  Work around this problem by executing a TLBI before returning to EL0.
+
+	  If unsure, say Y.
+
 config CAVIUM_ERRATUM_22375
 	bool "Cavium erratum 22375, 24313"
 	default y
diff --git a/arch/arm64/include/asm/acpi.h b/arch/arm64/include/asm/acpi.h
index 4d537d56eb84..6792a1f83f2a 100644
--- a/arch/arm64/include/asm/acpi.h
+++ b/arch/arm64/include/asm/acpi.h
@@ -9,6 +9,7 @@
 #ifndef _ASM_ACPI_H
 #define _ASM_ACPI_H
 
+#include <linux/cpuidle.h>
 #include <linux/efi.h>
 #include <linux/memblock.h>
 #include <linux/psci.h>
@@ -44,6 +45,24 @@
 
 #define ACPI_MADT_GICC_TRBE  (offsetof(struct acpi_madt_generic_interrupt, \
 	trbe_interrupt) + sizeof(u16))
+/*
+ * Arm® Functional Fixed Hardware Specification Version 1.2.
+ * Table 2: Arm Architecture context loss flags
+ */
+#define CPUIDLE_CORE_CTXT		BIT(0) /* Core context Lost */
+
+static inline unsigned int arch_get_idle_state_flags(u32 arch_flags)
+{
+	if (arch_flags & CPUIDLE_CORE_CTXT)
+		return CPUIDLE_FLAG_TIMER_STOP;
+
+	return 0;
+}
+#define arch_get_idle_state_flags arch_get_idle_state_flags
+
+#define CPUIDLE_TRACE_CTXT		BIT(1) /* Trace context loss */
+#define CPUIDLE_GICR_CTXT		BIT(2) /* GICR */
+#define CPUIDLE_GICD_CTXT		BIT(3) /* GICD */
 
 /* Basic configuration for ACPI */
 #ifdef	CONFIG_ACPI
diff --git a/arch/arm64/include/asm/cputype.h b/arch/arm64/include/asm/cputype.h
index 5f6f84837a49..74d00feb62f0 100644
--- a/arch/arm64/include/asm/cputype.h
+++ b/arch/arm64/include/asm/cputype.h
@@ -79,6 +79,7 @@
 #define ARM_CPU_PART_CORTEX_A78AE	0xD42
 #define ARM_CPU_PART_CORTEX_X1		0xD44
 #define ARM_CPU_PART_CORTEX_A510	0xD46
+#define ARM_CPU_PART_CORTEX_A520	0xD80
 #define ARM_CPU_PART_CORTEX_A710	0xD47
 #define ARM_CPU_PART_CORTEX_A715	0xD4D
 #define ARM_CPU_PART_CORTEX_X2		0xD48
@@ -148,6 +149,7 @@
 #define MIDR_CORTEX_A78AE	MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A78AE)
 #define MIDR_CORTEX_X1	MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_X1)
 #define MIDR_CORTEX_A510 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A510)
+#define MIDR_CORTEX_A520 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A520)
 #define MIDR_CORTEX_A710 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A710)
 #define MIDR_CORTEX_A715 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A715)
 #define MIDR_CORTEX_X2 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_X2)
diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c
index be66e94a21bd..5706e74c5578 100644
--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -730,6 +730,14 @@ const struct arm64_cpu_capabilities arm64_errata[] = {
 		.cpu_enable = cpu_clear_bf16_from_user_emulation,
 	},
 #endif
+#ifdef CONFIG_ARM64_ERRATUM_2966298
+	{
+		.desc = "ARM erratum 2966298",
+		.capability = ARM64_WORKAROUND_2966298,
+		/* Cortex-A520 r0p0 - r0p1 */
+		ERRATA_MIDR_REV_RANGE(MIDR_CORTEX_A520, 0, 0, 1),
+	},
+#endif
 #ifdef CONFIG_AMPERE_ERRATUM_AC03_CPU_38
 	{
 		.desc = "AmpereOne erratum AC03_CPU_38",
diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S
index 6ad61de03d0a..a6030913cd58 100644
--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -428,6 +428,10 @@ alternative_else_nop_endif
 	ldp	x28, x29, [sp, #16 * 14]
 
 	.if	\el == 0
+alternative_if ARM64_WORKAROUND_2966298
+	tlbi	vale1, xzr
+	dsb	nsh
+alternative_else_nop_endif
 alternative_if_not ARM64_UNMAP_KERNEL_AT_EL0
 	ldr	lr, [sp, #S_LR]
 	add	sp, sp, #PT_REGS_SIZE		// restore sp
diff --git a/arch/arm64/tools/cpucaps b/arch/arm64/tools/cpucaps
index c3f06fdef609..dea3dc89234b 100644
--- a/arch/arm64/tools/cpucaps
+++ b/arch/arm64/tools/cpucaps
@@ -84,6 +84,7 @@ WORKAROUND_2077057
 WORKAROUND_2457168
 WORKAROUND_2645198
 WORKAROUND_2658417
+WORKAROUND_2966298
 WORKAROUND_AMPERE_AC03_CPU_38
 WORKAROUND_TRBE_OVERWRITE_FILL_MODE
 WORKAROUND_TSB_FLUSH_FAILURE