The branch stable/14 has been updated by andrew: URL: https://cgit.FreeBSD.org/src/commit/?id=5b364c721f8e85c54f1bcfa073f7c59f29e494ba
commit 5b364c721f8e85c54f1bcfa073f7c59f29e494ba Author: Andrew Turner <[email protected]> AuthorDate: 2025-09-19 10:05:47 +0000 Commit: Andrew Turner <[email protected]> CommitDate: 2026-01-14 21:14:14 +0000 arm64: Read the CPU feature tunables once Rather than reading the CPU tunables each time we enable a feature just read them once on boot. Reading them early on non-boot CPUs causes issues where they try to allocate memory before the core is set up to do so. As they don't change it is safe to cache the state of them. Sponsored by: Arm Ltd Differential Revision: https://reviews.freebsd.org/D52578 (cherry picked from commit 5e0e2565288f3d1f1b4223d8bb53c7d70e0aa92c) --- sys/arm64/arm64/cpu_feat.c | 35 +++++++++++++++++++++++++---------- sys/arm64/include/cpu_feat.h | 3 +++ 2 files changed, 28 insertions(+), 10 deletions(-) diff --git a/sys/arm64/arm64/cpu_feat.c b/sys/arm64/arm64/cpu_feat.c index 11d42d5f3561..94114d47f846 100644 --- a/sys/arm64/arm64/cpu_feat.c +++ b/sys/arm64/arm64/cpu_feat.c @@ -54,6 +54,21 @@ enable_cpu_feat(uint32_t stage) SET_FOREACH(featp, cpu_feat_set) { feat = *featp; + /* Read any tunable the user may have set */ + if (stage == CPU_FEAT_EARLY_BOOT && PCPU_GET(cpuid) == 0) { + snprintf(tunable, sizeof(tunable), "hw.feat.%s", + feat->feat_name); + if (TUNABLE_BOOL_FETCH(tunable, &val)) { + if (val) { + feat->feat_flags |= + CPU_FEAT_USER_ENABLED; + } else { + feat->feat_flags |= + CPU_FEAT_USER_DISABLED; + } + } + } + /* Run the enablement code at the correct stage of boot */ if ((feat->feat_flags & CPU_FEAT_STAGE_MASK) != stage) continue; @@ -72,17 +87,17 @@ enable_cpu_feat(uint32_t stage) if (check_status == FEAT_ALWAYS_DISABLE) goto next; - snprintf(tunable, sizeof(tunable), "hw.feat.%s", - feat->feat_name); - if (TUNABLE_BOOL_FETCH(tunable, &val)) { - /* Is the feature disabled by the tunable? */ - if (!val) - goto next; - /* If enabled by the tunable then enable it */ - } else if (check_status == FEAT_DEFAULT_DISABLE) { - /* No tunable set and disabled by default */ + /* The user disabled the feature */ + if ((feat->feat_flags & CPU_FEAT_USER_DISABLED) != 0) + goto next; + + /* + * The feature was disabled by default and the user + * didn't enable it then skip. + */ + if (check_status == FEAT_DEFAULT_DISABLE && + (feat->feat_flags & CPU_FEAT_USER_ENABLED) == 0) goto next; - } /* * Check if the feature has any errata that may need a diff --git a/sys/arm64/include/cpu_feat.h b/sys/arm64/include/cpu_feat.h index 20c743a7e507..6a311d4000bb 100644 --- a/sys/arm64/include/cpu_feat.h +++ b/sys/arm64/include/cpu_feat.h @@ -73,6 +73,9 @@ typedef enum { #define CPU_FEAT_PER_CPU 0x00000000 #define CPU_FEAT_SYSTEM 0x00000010 +#define CPU_FEAT_USER_ENABLED 0x40000000 +#define CPU_FEAT_USER_DISABLED 0x80000000 + struct cpu_feat; typedef cpu_feat_en (cpu_feat_check)(const struct cpu_feat *, u_int);
