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-rw-r--r--arch/arm64/kernel/cpu_errata.c111
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diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c
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+/*
+ * Contains CPU specific errata definitions
+ *
+ * Copyright (C) 2014 ARM Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#define pr_fmt(fmt) "alternatives: " fmt
+
+#include <linux/types.h>
+#include <asm/cpu.h>
+#include <asm/cputype.h>
+#include <asm/cpufeature.h>
+
+#define MIDR_CORTEX_A53 MIDR_CPU_PART(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A53)
+#define MIDR_CORTEX_A57 MIDR_CPU_PART(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A57)
+
+/*
+ * Add a struct or another datatype to the union below if you need
+ * different means to detect an affected CPU.
+ */
+struct arm64_cpu_capabilities {
+ const char *desc;
+ u16 capability;
+ bool (*is_affected)(struct arm64_cpu_capabilities *);
+ union {
+ struct {
+ u32 midr_model;
+ u32 midr_range_min, midr_range_max;
+ };
+ };
+};
+
+#define CPU_MODEL_MASK (MIDR_IMPLEMENTOR_MASK | MIDR_PARTNUM_MASK | \
+ MIDR_ARCHITECTURE_MASK)
+
+static bool __maybe_unused
+is_affected_midr_range(struct arm64_cpu_capabilities *entry)
+{
+ u32 midr = read_cpuid_id();
+
+ if ((midr & CPU_MODEL_MASK) != entry->midr_model)
+ return false;
+
+ midr &= MIDR_REVISION_MASK | MIDR_VARIANT_MASK;
+
+ return (midr >= entry->midr_range_min && midr <= entry->midr_range_max);
+}
+
+#define MIDR_RANGE(model, min, max) \
+ .is_affected = is_affected_midr_range, \
+ .midr_model = model, \
+ .midr_range_min = min, \
+ .midr_range_max = max
+
+struct arm64_cpu_capabilities arm64_errata[] = {
+#if defined(CONFIG_ARM64_ERRATUM_826319) || \
+ defined(CONFIG_ARM64_ERRATUM_827319) || \
+ defined(CONFIG_ARM64_ERRATUM_824069)
+ {
+ /* Cortex-A53 r0p[012] */
+ .desc = "ARM errata 826319, 827319, 824069",
+ .capability = ARM64_WORKAROUND_CLEAN_CACHE,
+ MIDR_RANGE(MIDR_CORTEX_A53, 0x00, 0x02),
+ },
+#endif
+#ifdef CONFIG_ARM64_ERRATUM_819472
+ {
+ /* Cortex-A53 r0p[01] */
+ .desc = "ARM errata 819472",
+ .capability = ARM64_WORKAROUND_CLEAN_CACHE,
+ MIDR_RANGE(MIDR_CORTEX_A53, 0x00, 0x01),
+ },
+#endif
+#ifdef CONFIG_ARM64_ERRATUM_832075
+ {
+ /* Cortex-A57 r0p0 - r1p2 */
+ .desc = "ARM erratum 832075",
+ .capability = ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE,
+ MIDR_RANGE(MIDR_CORTEX_A57, 0x00, 0x12),
+ },
+#endif
+ {
+ }
+};
+
+void check_local_cpu_errata(void)
+{
+ struct arm64_cpu_capabilities *cpus = arm64_errata;
+ int i;
+
+ for (i = 0; cpus[i].desc; i++) {
+ if (!cpus[i].is_affected(&cpus[i]))
+ continue;
+
+ if (!cpus_have_cap(cpus[i].capability))
+ pr_info("enabling workaround for %s\n", cpus[i].desc);
+ cpus_set_cap(cpus[i].capability);
+ }
+}