diff options
Diffstat (limited to 'arch/arm64')
| -rw-r--r-- | arch/arm64/include/asm/cpufeature.h | 11 | ||||
| -rw-r--r-- | arch/arm64/include/asm/processor.h | 2 | ||||
| -rw-r--r-- | arch/arm64/kernel/cpufeature.c | 97 | ||||
| -rw-r--r-- | arch/arm64/kernel/cpuinfo.c | 1 | ||||
| -rw-r--r-- | arch/arm64/kernel/smp.c | 7 | ||||
| -rw-r--r-- | arch/arm64/mm/fault.c | 2 |
6 files changed, 111 insertions, 9 deletions
diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h index 12d883a067c4..1603ae84ea45 100644 --- a/arch/arm64/include/asm/cpufeature.h +++ b/arch/arm64/include/asm/cpufeature.h @@ -70,7 +70,7 @@ struct arm64_cpu_capabilities { const char *desc; u16 capability; bool (*matches)(const struct arm64_cpu_capabilities *); - void (*enable)(void); + void (*enable)(void *); /* Called on all active CPUs */ union { struct { /* To be used for erratum handling only */ u32 midr_model; @@ -140,7 +140,14 @@ void __init setup_cpu_features(void); void update_cpu_capabilities(const struct arm64_cpu_capabilities *caps, const char *info); void check_local_cpu_errata(void); -void check_local_cpu_features(void); + +#ifdef CONFIG_HOTPLUG_CPU +void verify_local_cpu_capabilities(void); +#else +static inline void verify_local_cpu_capabilities(void) +{ +} +#endif u64 read_system_reg(u32 id); diff --git a/arch/arm64/include/asm/processor.h b/arch/arm64/include/asm/processor.h index 98f32355dc97..4acb7ca94fcd 100644 --- a/arch/arm64/include/asm/processor.h +++ b/arch/arm64/include/asm/processor.h @@ -186,6 +186,6 @@ static inline void spin_lock_prefetch(const void *x) #endif -void cpu_enable_pan(void); +void cpu_enable_pan(void *__unused); #endif /* __ASM_PROCESSOR_H */ diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index 78c4cb7af20e..e002cadf84bf 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -23,6 +23,7 @@ #include <linux/types.h> #include <asm/cpu.h> #include <asm/cpufeature.h> +#include <asm/cpu_ops.h> #include <asm/processor.h> #include <asm/sysreg.h> @@ -645,19 +646,101 @@ void update_cpu_capabilities(const struct arm64_cpu_capabilities *caps, } /* - * Run through the enabled capabilities and enable() it on the CPUs + * Run through the enabled capabilities and enable() it on all active + * CPUs */ void enable_cpu_capabilities(const struct arm64_cpu_capabilities *caps) { int i; + for (i = 0; caps[i].desc; i++) + if (caps[i].enable && cpus_have_cap(caps[i].capability)) + on_each_cpu(caps[i].enable, NULL, true); +} + +#ifdef CONFIG_HOTPLUG_CPU + +/* + * Flag to indicate if we have computed the system wide + * capabilities based on the boot time active CPUs. This + * will be used to determine if a new booting CPU should + * go through the verification process to make sure that it + * supports the system capabilities, without using a hotplug + * notifier. + */ +static bool sys_caps_initialised; + +static inline void set_sys_caps_initialised(void) +{ + sys_caps_initialised = true; +} + +/* + * Park the CPU which doesn't have the capability as advertised + * by the system. + */ +static void fail_incapable_cpu(char *cap_type, + const struct arm64_cpu_capabilities *cap) +{ + int cpu = smp_processor_id(); + + pr_crit("CPU%d: missing %s : %s\n", cpu, cap_type, cap->desc); + /* Mark this CPU absent */ + set_cpu_present(cpu, 0); + + /* Check if we can park ourselves */ + if (cpu_ops[cpu] && cpu_ops[cpu]->cpu_die) + cpu_ops[cpu]->cpu_die(cpu); + asm( + "1: wfe\n" + " wfi\n" + " b 1b"); +} + +/* + * Run through the enabled system capabilities and enable() it on this CPU. + * The capabilities were decided based on the available CPUs at the boot time. + * Any new CPU should match the system wide status of the capability. If the + * new CPU doesn't have a capability which the system now has enabled, we + * cannot do anything to fix it up and could cause unexpected failures. So + * we park the CPU. + */ +void verify_local_cpu_capabilities(void) +{ + int i; + const struct arm64_cpu_capabilities *caps; + + /* + * If we haven't computed the system capabilities, there is nothing + * to verify. + */ + if (!sys_caps_initialised) + return; + + caps = arm64_features; for (i = 0; caps[i].desc; i++) { - if (cpus_have_cap(caps[i].capability) && caps[i].enable) - caps[i].enable(); + if (!cpus_have_cap(caps[i].capability)) + continue; + /* + * If the new CPU misses an advertised feature, we cannot proceed + * further, park the cpu. + */ + if (!caps[i].matches(&caps[i])) + fail_incapable_cpu("arm64_features", &caps[i]); + if (caps[i].enable) + caps[i].enable(NULL); } } -void check_local_cpu_features(void) +#else /* !CONFIG_HOTPLUG_CPU */ + +static inline void set_sys_caps_initialised(void) +{ +} + +#endif /* CONFIG_HOTPLUG_CPU */ + +static void setup_feature_capabilities(void) { update_cpu_capabilities(arm64_features, "detected feature:"); enable_cpu_capabilities(arm64_features); @@ -670,6 +753,12 @@ void __init setup_cpu_features(void) u32 cwg; int cls; + /* Set the CPU feature capabilies */ + setup_feature_capabilities(); + + /* Advertise that we have computed the system capabilities */ + set_sys_caps_initialised(); + /* * Check for sane CTR_EL0.CWG value. */ diff --git a/arch/arm64/kernel/cpuinfo.c b/arch/arm64/kernel/cpuinfo.c index f25869ea2646..789fbea92b79 100644 --- a/arch/arm64/kernel/cpuinfo.c +++ b/arch/arm64/kernel/cpuinfo.c @@ -229,7 +229,6 @@ static void __cpuinfo_store_cpu(struct cpuinfo_arm64 *info) cpuinfo_detect_icache_policy(info); check_local_cpu_errata(); - check_local_cpu_features(); } void cpuinfo_store_cpu(void) diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index d1d00499f0cf..2bbdc0e4fd14 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -156,6 +156,13 @@ asmlinkage void secondary_start_kernel(void) preempt_disable(); trace_hardirqs_off(); + /* + * If the system has established the capabilities, make sure + * this CPU ticks all of those. If it doesn't, the CPU will + * fail to come online. + */ + verify_local_cpu_capabilities(); + if (cpu_ops[cpu]->cpu_postboot) cpu_ops[cpu]->cpu_postboot(); diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c index aba9ead1384c..066d5aea16c6 100644 --- a/arch/arm64/mm/fault.c +++ b/arch/arm64/mm/fault.c @@ -555,7 +555,7 @@ asmlinkage int __exception do_debug_exception(unsigned long addr, } #ifdef CONFIG_ARM64_PAN -void cpu_enable_pan(void) +void cpu_enable_pan(void *__unused) { config_sctlr_el1(SCTLR_EL1_SPAN, 0); } |