Merge remote-tracking branch 'drm/drm-next'

[karo-tx-linux.git] / arch / arm64 / kernel / cpufeature.c

diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index 5c90aa490a2bee2368ae45bba2628603afe1c659..3615d7d7c9af65520c5b835d4e58d130ae6c061e 100644 (file)
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -621,6 +621,18 @@ static bool has_useable_gicv3_cpuif(const struct arm64_cpu_capabilities *entry)
        return has_sre;
 }
 
+static bool has_no_hw_prefetch(const struct arm64_cpu_capabilities *entry)
+{
+       u32 midr = read_cpuid_id();
+       u32 rv_min, rv_max;
+
+       /* Cavium ThunderX pass 1.x and 2.x */
+       rv_min = 0;
+       rv_max = (1 << MIDR_VARIANT_SHIFT) | MIDR_REVISION_MASK;
+
+       return MIDR_IS_CPU_MODEL_RANGE(midr, MIDR_THUNDERX, rv_min, rv_max);
+}
+
 static const struct arm64_cpu_capabilities arm64_features[] = {
        {
                .desc = "GIC system register CPU interface",
@@ -651,6 +663,11 @@ static const struct arm64_cpu_capabilities arm64_features[] = {
                .min_field_value = 2,
        },
 #endif /* CONFIG_AS_LSE && CONFIG_ARM64_LSE_ATOMICS */
+       {
+               .desc = "Software prefetching using PRFM",
+               .capability = ARM64_HAS_NO_HW_PREFETCH,
+               .matches = has_no_hw_prefetch,
+       },
        {},
 };