drivers: base: cacheinfo: Add variable to record max cache line size

Add coherency_max_size variable to record the maximum cache line size
for different cache levels. If it is available, we will synchronize
it as cache line size, otherwise we will use CTR_EL0.CWG reporting
in cache_line_size() for arm64.

Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Jeremy Linton <jeremy.linton@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

diff --git a/drivers/base/cacheinfo.c b/drivers/base/cacheinfo.c
index a7359535caf5dfad5ec0c0a95da54d59174b0159..8827c60f51e25a0cd24bfa5180fca6aa48c3cec3 100644 (file)
--- a/drivers/base/cacheinfo.c
+++ b/drivers/base/cacheinfo.c
@@ -213,6 +213,8 @@ int __weak cache_setup_acpi(unsigned int cpu)
        return -ENOTSUPP;
 }
 
+unsigned int coherency_max_size;
+
 static int cache_shared_cpu_map_setup(unsigned int cpu)
 {
        struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
@@ -251,6 +253,9 @@ static int cache_shared_cpu_map_setup(unsigned int cpu)
                                cpumask_set_cpu(i, &this_leaf->shared_cpu_map);
                        }
                }
+               /* record the maximum cache line size */
+               if (this_leaf->coherency_line_size > coherency_max_size)
+                       coherency_max_size = this_leaf->coherency_line_size;
        }
 
        return 0;

diff --git a/include/linux/cacheinfo.h b/include/linux/cacheinfo.h
index 70e19bc6cc9fc29230a1b5774112414a2f75e89d..46b92cd61d0c8252a354eeb4b2f84965e1513aaf 100644 (file)
--- a/include/linux/cacheinfo.h
+++ b/include/linux/cacheinfo.h
@@ -17,6 +17,8 @@ enum cache_type {
        CACHE_TYPE_UNIFIED = BIT(2),
 };
 
+extern unsigned int coherency_max_size;
+
 /**
  * struct cacheinfo - represent a cache leaf node
  * @id: This cache's id. It is unique among caches with the same (type, level).