diff options
Diffstat (limited to 'drivers/base/cacheinfo.c')
| -rw-r--r-- | drivers/base/cacheinfo.c | 142 |
1 files changed, 109 insertions, 33 deletions
diff --git a/drivers/base/cacheinfo.c b/drivers/base/cacheinfo.c index f6573c335f4c..bba3482ddeb8 100644 --- a/drivers/base/cacheinfo.c +++ b/drivers/base/cacheinfo.c @@ -14,7 +14,7 @@ #include <linux/cpu.h> #include <linux/device.h> #include <linux/init.h> -#include <linux/of_device.h> +#include <linux/of.h> #include <linux/sched.h> #include <linux/slab.h> #include <linux/smp.h> @@ -28,6 +28,9 @@ static DEFINE_PER_CPU(struct cpu_cacheinfo, ci_cpu_cacheinfo); #define per_cpu_cacheinfo_idx(cpu, idx) \ (per_cpu_cacheinfo(cpu) + (idx)) +/* Set if no cache information is found in DT/ACPI. */ +static bool use_arch_info; + struct cpu_cacheinfo *get_cpu_cacheinfo(unsigned int cpu) { return ci_cacheinfo(cpu); @@ -38,11 +41,11 @@ static inline bool cache_leaves_are_shared(struct cacheinfo *this_leaf, { /* * For non DT/ACPI systems, assume unique level 1 caches, - * system-wide shared caches for all other levels. This will be used - * only if arch specific code has not populated shared_cpu_map + * system-wide shared caches for all other levels. */ - if (!(IS_ENABLED(CONFIG_OF) || IS_ENABLED(CONFIG_ACPI))) - return !(this_leaf->level == 1); + if (!(IS_ENABLED(CONFIG_OF) || IS_ENABLED(CONFIG_ACPI)) || + use_arch_info) + return (this_leaf->level != 1) && (sib_leaf->level != 1); if ((sib_leaf->attributes & CACHE_ID) && (this_leaf->attributes & CACHE_ID)) @@ -79,6 +82,9 @@ bool last_level_cache_is_shared(unsigned int cpu_x, unsigned int cpu_y) } #ifdef CONFIG_OF + +static bool of_check_cache_nodes(struct device_node *np); + /* OF properties to query for a given cache type */ struct cache_type_info { const char *size_prop; @@ -206,6 +212,11 @@ static int cache_setup_of_node(unsigned int cpu) return -ENOENT; } + if (!of_check_cache_nodes(np)) { + of_node_put(np); + return -ENOENT; + } + prev = np; while (index < cache_leaves(cpu)) { @@ -230,6 +241,25 @@ static int cache_setup_of_node(unsigned int cpu) return 0; } +static bool of_check_cache_nodes(struct device_node *np) +{ + struct device_node *next; + + if (of_property_present(np, "cache-size") || + of_property_present(np, "i-cache-size") || + of_property_present(np, "d-cache-size") || + of_property_present(np, "cache-unified")) + return true; + + next = of_find_next_cache_node(np); + if (next) { + of_node_put(next); + return true; + } + + return false; +} + static int of_count_cache_leaves(struct device_node *np) { unsigned int leaves = 0; @@ -261,6 +291,11 @@ int init_of_cache_level(unsigned int cpu) struct device_node *prev = NULL; unsigned int levels = 0, leaves, level; + if (!of_check_cache_nodes(np)) { + of_node_put(np); + return -ENOENT; + } + leaves = of_count_cache_leaves(np); if (leaves > 0) levels = 1; @@ -312,6 +347,10 @@ static int cache_setup_properties(unsigned int cpu) else if (!acpi_disabled) ret = cache_setup_acpi(cpu); + // Assume there is no cache information available in DT/ACPI from now. + if (ret && use_arch_cache_info()) + use_arch_info = true; + return ret; } @@ -330,7 +369,7 @@ static int cache_shared_cpu_map_setup(unsigned int cpu) * to update the shared cpu_map if the cache attributes were * populated early before all the cpus are brought online */ - if (!last_level_cache_is_valid(cpu)) { + if (!last_level_cache_is_valid(cpu) && !use_arch_info) { ret = cache_setup_properties(cpu); if (ret) return ret; @@ -398,6 +437,11 @@ static void free_cache_attributes(unsigned int cpu) cache_shared_cpu_map_remove(cpu); } +int __weak early_cache_level(unsigned int cpu) +{ + return -ENOENT; +} + int __weak init_cache_level(unsigned int cpu) { return -ENOENT; @@ -423,63 +467,95 @@ int allocate_cache_info(int cpu) int fetch_cache_info(unsigned int cpu) { - struct cpu_cacheinfo *this_cpu_ci; + struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu); unsigned int levels = 0, split_levels = 0; int ret; if (acpi_disabled) { ret = init_of_cache_level(cpu); - if (ret < 0) - return ret; } else { ret = acpi_get_cache_info(cpu, &levels, &split_levels); - if (ret < 0) + if (!ret) { + this_cpu_ci->num_levels = levels; + /* + * This assumes that: + * - there cannot be any split caches (data/instruction) + * above a unified cache + * - data/instruction caches come by pair + */ + this_cpu_ci->num_leaves = levels + split_levels; + } + } + + if (ret || !cache_leaves(cpu)) { + ret = early_cache_level(cpu); + if (ret) return ret; - this_cpu_ci = get_cpu_cacheinfo(cpu); - this_cpu_ci->num_levels = levels; - /* - * This assumes that: - * - there cannot be any split caches (data/instruction) - * above a unified cache - * - data/instruction caches come by pair - */ - this_cpu_ci->num_leaves = levels + split_levels; + if (!cache_leaves(cpu)) + return -ENOENT; + + this_cpu_ci->early_ci_levels = true; } - if (!cache_leaves(cpu)) - return -ENOENT; return allocate_cache_info(cpu); } -int detect_cache_attributes(unsigned int cpu) +static inline int init_level_allocate_ci(unsigned int cpu) { - int ret; + unsigned int early_leaves = cache_leaves(cpu); /* Since early initialization/allocation of the cacheinfo is allowed * via fetch_cache_info() and this also gets called as CPU hotplug * callbacks via cacheinfo_cpu_online, the init/alloc can be skipped * as it will happen only once (the cacheinfo memory is never freed). - * Just populate the cacheinfo. + * Just populate the cacheinfo. However, if the cacheinfo has been + * allocated early through the arch-specific early_cache_level() call, + * there is a chance the info is wrong (this can happen on arm64). In + * that case, call init_cache_level() anyway to give the arch-specific + * code a chance to make things right. */ - if (per_cpu_cacheinfo(cpu)) - goto populate_leaves; + if (per_cpu_cacheinfo(cpu) && !ci_cacheinfo(cpu)->early_ci_levels) + return 0; if (init_cache_level(cpu) || !cache_leaves(cpu)) return -ENOENT; - ret = allocate_cache_info(cpu); + /* + * Now that we have properly initialized the cache level info, make + * sure we don't try to do that again the next time we are called + * (e.g. as CPU hotplug callbacks). + */ + ci_cacheinfo(cpu)->early_ci_levels = false; + + if (cache_leaves(cpu) <= early_leaves) + return 0; + + kfree(per_cpu_cacheinfo(cpu)); + return allocate_cache_info(cpu); +} + +int detect_cache_attributes(unsigned int cpu) +{ + int ret; + + ret = init_level_allocate_ci(cpu); if (ret) return ret; -populate_leaves: /* - * populate_cache_leaves() may completely setup the cache leaves and - * shared_cpu_map or it may leave it partially setup. + * If LLC is valid the cache leaves were already populated so just go to + * update the cpu map. */ - ret = populate_cache_leaves(cpu); - if (ret) - goto free_ci; + if (!last_level_cache_is_valid(cpu)) { + /* + * populate_cache_leaves() may completely setup the cache leaves and + * shared_cpu_map or it may leave it partially setup. + */ + ret = populate_cache_leaves(cpu); + if (ret) + goto free_ci; + } /* * For systems using DT for cache hierarchy, fw_token |