Commit e8002e02 authored by Ard Biesheuvel's avatar Ard Biesheuvel Committed by Will Deacon

arm64/errata: add REVIDR handling to framework

In some cases, core variants that are affected by a certain erratum
also exist in versions that have the erratum fixed, and this fact is
recorded in a dedicated bit in system register REVIDR_EL1.

Since the architecture does not require that a certain bit retains
its meaning across different variants of the same model, each such
REVIDR bit is tightly coupled to a certain revision/variant value,
and so we need a list of revidr_mask/midr pairs to carry this

So add the struct member and the associated macros and handling to
allow REVIDR fixes to be taken into account.
Signed-off-by: default avatarArd Biesheuvel <>
Signed-off-by: default avatarWill Deacon <>
parent a257e025
......@@ -105,6 +105,10 @@ struct arm64_cpu_capabilities {
struct { /* To be used for erratum handling only */
u32 midr_model;
u32 midr_range_min, midr_range_max;
const struct arm64_midr_revidr {
u32 midr_rv; /* revision/variant */
u32 revidr_mask;
} * const fixed_revs;
struct { /* Feature register checking */
......@@ -24,10 +24,22 @@
static bool __maybe_unused
is_affected_midr_range(const struct arm64_cpu_capabilities *entry, int scope)
const struct arm64_midr_revidr *fix;
u32 midr = read_cpuid_id(), revidr;
WARN_ON(scope != SCOPE_LOCAL_CPU || preemptible());
return MIDR_IS_CPU_MODEL_RANGE(read_cpuid_id(), entry->midr_model,
if (!MIDR_IS_CPU_MODEL_RANGE(midr, entry->midr_model,
return false;
revidr = read_cpuid(REVIDR_EL1);
for (fix = entry->fixed_revs; fix && fix->revidr_mask; fix++)
if (midr == fix->midr_rv && (revidr & fix->revidr_mask))
return false;
return true;
static bool __maybe_unused
......@@ -242,6 +254,9 @@ static int qcom_enable_link_stack_sanitization(void *data)
.midr_range_min = 0, \
#define MIDR_FIXED(rev, revidr_mask) \
.fixed_revs = (struct arm64_midr_revidr[]){{ (rev), (revidr_mask) }, {}}
const struct arm64_cpu_capabilities arm64_errata[] = {
#if defined(CONFIG_ARM64_ERRATUM_826319) || \
defined(CONFIG_ARM64_ERRATUM_827319) || \
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