diff options
Diffstat (limited to 'arch/arm64/kernel/cpuinfo.c')
| -rw-r--r-- | arch/arm64/kernel/cpuinfo.c | 28 |
1 files changed, 26 insertions, 2 deletions
diff --git a/arch/arm64/kernel/cpuinfo.c b/arch/arm64/kernel/cpuinfo.c index 177169623026..504fdaa8367e 100644 --- a/arch/arm64/kernel/cpuinfo.c +++ b/arch/arm64/kernel/cpuinfo.c @@ -20,8 +20,10 @@ #include <asm/cputype.h> #include <linux/bitops.h> +#include <linux/bug.h> #include <linux/init.h> #include <linux/kernel.h> +#include <linux/preempt.h> #include <linux/printk.h> #include <linux/smp.h> @@ -47,8 +49,18 @@ static void cpuinfo_detect_icache_policy(struct cpuinfo_arm64 *info) unsigned int cpu = smp_processor_id(); u32 l1ip = CTR_L1IP(info->reg_ctr); - if (l1ip != ICACHE_POLICY_PIPT) - set_bit(ICACHEF_ALIASING, &__icache_flags); + if (l1ip != ICACHE_POLICY_PIPT) { + /* + * VIPT caches are non-aliasing if the VA always equals the PA + * in all bit positions that are covered by the index. This is + * the case if the size of a way (# of sets * line size) does + * not exceed PAGE_SIZE. + */ + u32 waysize = icache_get_numsets() * icache_get_linesize(); + + if (l1ip != ICACHE_POLICY_VIPT || waysize > PAGE_SIZE) + set_bit(ICACHEF_ALIASING, &__icache_flags); + } if (l1ip == ICACHE_POLICY_AIVIVT) set_bit(ICACHEF_AIVIVT, &__icache_flags); @@ -190,3 +202,15 @@ void __init cpuinfo_store_boot_cpu(void) boot_cpu_data = *info; } + +u64 __attribute_const__ icache_get_ccsidr(void) +{ + u64 ccsidr; + + WARN_ON(preemptible()); + + /* Select L1 I-cache and read its size ID register */ + asm("msr csselr_el1, %1; isb; mrs %0, ccsidr_el1" + : "=r"(ccsidr) : "r"(1L)); + return ccsidr; +} |