From 5b4747c5dce7a873e1e7fe1608835825f714267a Mon Sep 17 00:00:00 2001 From: Suzuki K Poulose Date: Mon, 26 Mar 2018 15:12:32 +0100 Subject: arm64: capabilities: Add flags to handle the conflicts on late CPU When a CPU is brought up, it is checked against the caps that are known to be enabled on the system (via verify_local_cpu_capabilities()). Based on the state of the capability on the CPU vs. that of System we could have the following combinations of conflict. x-----------------------------x | Type | System | Late CPU | |-----------------------------| | a | y | n | |-----------------------------| | b | n | y | x-----------------------------x Case (a) is not permitted for caps which are system features, which the system expects all the CPUs to have (e.g VHE). While (a) is ignored for all errata work arounds. However, there could be exceptions to the plain filtering approach. e.g, KPTI is an optional feature for a late CPU as long as the system already enables it. Case (b) is not permitted for errata work arounds that cannot be activated after the kernel has finished booting.And we ignore (b) for features. Here, yet again, KPTI is an exception, where if a late CPU needs KPTI we are too late to enable it (because we change the allocation of ASIDs etc). Add two different flags to indicate how the conflict should be handled. ARM64_CPUCAP_PERMITTED_FOR_LATE_CPU - CPUs may have the capability ARM64_CPUCAP_OPTIONAL_FOR_LATE_CPU - CPUs may not have the cappability. Now that we have the flags to describe the behavior of the errata and the features, as we treat them, define types for ERRATUM and FEATURE. Cc: Will Deacon Cc: Mark Rutland Reviewed-by: Dave Martin Signed-off-by: Suzuki K Poulose Signed-off-by: Will Deacon --- arch/arm64/kernel/cpu_errata.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'arch/arm64/kernel/cpu_errata.c') diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c index 2b5233157af1..f5ab9545c5ea 100644 --- a/arch/arm64/kernel/cpu_errata.c +++ b/arch/arm64/kernel/cpu_errata.c @@ -238,14 +238,14 @@ qcom_enable_link_stack_sanitization(const struct arm64_cpu_capabilities *entry) #endif /* CONFIG_HARDEN_BRANCH_PREDICTOR */ #define MIDR_RANGE(model, min, max) \ - .type = ARM64_CPUCAP_SCOPE_LOCAL_CPU, \ + .type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM, \ .matches = is_affected_midr_range, \ .midr_model = model, \ .midr_range_min = min, \ .midr_range_max = max #define MIDR_ALL_VERSIONS(model) \ - .type = ARM64_CPUCAP_SCOPE_LOCAL_CPU, \ + .type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM, \ .matches = is_affected_midr_range, \ .midr_model = model, \ .midr_range_min = 0, \ @@ -361,7 +361,7 @@ const struct arm64_cpu_capabilities arm64_errata[] = { .desc = "Mismatched cache line size", .capability = ARM64_MISMATCHED_CACHE_LINE_SIZE, .matches = has_mismatched_cache_line_size, - .type = ARM64_CPUCAP_SCOPE_LOCAL_CPU, + .type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM, .cpu_enable = cpu_enable_trap_ctr_access, }, #ifdef CONFIG_QCOM_FALKOR_ERRATUM_1003 @@ -375,7 +375,7 @@ const struct arm64_cpu_capabilities arm64_errata[] = { { .desc = "Qualcomm Technologies Kryo erratum 1003", .capability = ARM64_WORKAROUND_QCOM_FALKOR_E1003, - .type = ARM64_CPUCAP_SCOPE_LOCAL_CPU, + .type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM, .midr_model = MIDR_QCOM_KRYO, .matches = is_kryo_midr, }, -- cgit v1.2.3-55-g7522