Or in other words, make fail_incapable_cpu() reusable. We use fail_incapable_cpu() to kill a secondary CPU early during the bringup, which doesn't have the system advertised capabilities. This patch makes the routine more generic, to kill a secondary booting CPU, getting rid of the dependency on capability struct. This can be used by checks which are not necessarily attached to a capability struct (e.g, cpu ASIDBits).
In that process, renames the function to cpu_die_early() to better match its functionality. This will be later moved to arch/arm64/kernel/smp.c. Cc: Will Deacon <will.dea...@arm.com> Cc: Mark Rutland <mark.rutl...@arm.com> Cc: Catalin Marinas <catalin.mari...@arm.com> Signed-off-by: Suzuki K. Poulose <suzuki.poul...@arm.com> --- arch/arm64/kernel/cpufeature.c | 33 ++++++++++++++++++++------------- 1 file changed, 20 insertions(+), 13 deletions(-) diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index 0669c63..581b779 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -826,25 +826,26 @@ static u64 __raw_read_system_reg(u32 sys_id) } /* - * Park the CPU which doesn't have the capability as advertised - * by the system. + * Kill the calling secondary CPU, early in bringup before it is turned + * online. */ -static void fail_incapable_cpu(char *cap_type, - const struct arm64_cpu_capabilities *cap) +void cpu_die_early(void) { int cpu = smp_processor_id(); - pr_crit("CPU%d: missing %s : %s\n", cpu, cap_type, cap->desc); + pr_crit("CPU%d: will not boot\n", cpu); + /* 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"); + + for (;;) { + wfe(); + wfi(); + } } /* @@ -875,8 +876,11 @@ void verify_local_cpu_capabilities(void) * If the new CPU misses an advertised feature, we cannot proceed * further, park the cpu. */ - if (!feature_matches(__raw_read_system_reg(caps[i].sys_reg), &caps[i])) - fail_incapable_cpu("arm64_features", &caps[i]); + if (!feature_matches(__raw_read_system_reg(caps[i].sys_reg), &caps[i])) { + pr_crit("CPU%d: missing feature: %s\n", + smp_processor_id(), caps[i].desc); + cpu_die_early(); + } if (caps[i].enable) caps[i].enable(NULL); } @@ -884,8 +888,11 @@ void verify_local_cpu_capabilities(void) for (i = 0, caps = arm64_hwcaps; caps[i].desc; i++) { if (!cpus_have_hwcap(&caps[i])) continue; - if (!feature_matches(__raw_read_system_reg(caps[i].sys_reg), &caps[i])) - fail_incapable_cpu("arm64_hwcaps", &caps[i]); + if (!feature_matches(__raw_read_system_reg(caps[i].sys_reg), &caps[i])) { + pr_crit("CPU%d: missing HWCAP: %s\n", + smp_processor_id(), caps[i].desc); + cpu_die_early(); + } } } -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/