[PATCH 2/2] dt-bindings: arm: cpus: Add edac-enabled property

[Sascha Hauer]

Some CPUs like the Cortex-A53 and Cortex-A57 have Error Detection And
Correction (EDAC) support on their L1 and L2 caches. This is implemented
in implementation defined registers, so usage of this functionality is
not safe in virtualized environments or when EL3 already uses these
registers.
This patch adds a edac-enabled flag which can be explicitly set when
EDAC can be used.

Signed-off-by: Sascha Hauer <s.hauer at pengutronix.de>
---
 Documentation/devicetree/bindings/arm/cpus.yaml | 6 ++++++
 drivers/edac/cortex_arm64_l1_l2.c               | 7 +++++--
 2 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/arm/cpus.yaml b/Documentation/devicetree/bindings/arm/cpus.yaml
index f02fd10de604..80dcf90f3e78 100644
--- a/Documentation/devicetree/bindings/arm/cpus.yaml
+++ b/Documentation/devicetree/bindings/arm/cpus.yaml
@@ -269,6 +269,12 @@ properties:
       For PSCI based platforms, the name corresponding to the index of the PSCI
       PM domain provider, must be "psci".
 
+  edac-enabled:
+    $ref: '/schemas/types.yaml#/definitions/flag'
+    description:
+      Some CPUs support Error Detection And Correction (EDAC) on their L1 and
+      L2 caches. This flag marks this function as usable.
+
   qcom,saw:
     $ref: '/schemas/types.yaml#/definitions/phandle'
     description: |
diff --git a/drivers/edac/cortex_arm64_l1_l2.c b/drivers/edac/cortex_arm64_l1_l2.c
index 3b1e2f3ccab6..6d5355bae80c 100644
--- a/drivers/edac/cortex_arm64_l1_l2.c
+++ b/drivers/edac/cortex_arm64_l1_l2.c
@@ -190,8 +190,11 @@ static int __init cortex_arm64_edac_driver_init(void)
 	for_each_possible_cpu(cpu) {
 		np = of_get_cpu_node(cpu, NULL);
 
-		if (of_match_node(cortex_arm64_edac_of_match, np))
-			cpumask_set_cpu(cpu, &compat_mask);
+		if (!of_match_node(cortex_arm64_edac_of_match, np))
+			continue;
+		if (!of_property_read_bool(np, "edac-enabled"))
+			continue;
+		cpumask_set_cpu(cpu, &compat_mask);
 	}
 
 	if (cpumask_empty(&compat_mask))
-- 
2.20.1