[PATCH v9 08/12] arm64: Add support for ACPI based firmware tables

Jeremy Linton
2018-05-11T23:58:03Z

The /sys cache entries should support ACPI/PPTT generated cache
topology information. For arm64, if ACPI is enabled, determine
the max number of cache levels and populate them using the PPTT
table if one is available.

Signed-off-by: Jeremy Linton <jeremy.linton@arm.com>
Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Tested-by: Vijaya Kumar K <vkilari@codeaurora.org>
Tested-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Tested-by: Tomasz Nowicki <Tomasz.Nowicki@cavium.com>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
---
arch/arm64/kernel/cacheinfo.c | 15 ++++++++++-----
1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/arch/arm64/kernel/cacheinfo.c b/arch/arm64/kernel/cacheinfo.c
index 380f2e2fbed5..0bf0a835122f 100644
--- a/arch/arm64/kernel/cacheinfo.c
+++ b/arch/arm64/kernel/cacheinfo.c
@@ -17,6 +17,7 @@
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/

+#include <linux/acpi.h>
#include <linux/cacheinfo.h>
#include <linux/of.h>

@@ -46,7 +47,7 @@ static void ci_leaf_init(struct cacheinfo *this_leaf,

static int __init_cache_level(unsigned int cpu)
{
- unsigned int ctype, level, leaves, of_level;
+ unsigned int ctype, level, leaves, fw_level;
struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);

for (level = 1, leaves = 0; level <= MAX_CACHE_LEVEL; level++) {
@@ -59,15 +60,19 @@ static int __init_cache_level(unsigned int cpu)
leaves += (ctype == CACHE_TYPE_SEPARATE) ? 2 : 1;
}

- of_level = of_find_last_cache_level(cpu);
- if (level < of_level) {
+ if (acpi_disabled)
+ fw_level = of_find_last_cache_level(cpu);
+ else
+ fw_level = acpi_find_last_cache_level(cpu);
+
+ if (level < fw_level) {
/*
* some external caches not specified in CLIDR_EL1
* the information may be available in the device tree
* only unified external caches are considered here
*/
- leaves += (of_level - level);
- level = of_level;
+ leaves += (fw_level - level);
+ level = fw_level;
}

this_cpu_ci->num_levels = level;
--
2.13.6