[PATCH v5 2/4] dt-bindings: arm: Document reboot mode magic

Elliot Berman quic_eberman at quicinc.com
Mon Jun 17 10:18:08 PDT 2024


Add bindings to describe vendor-specific reboot modes. Values here
correspond to valid parameters to vendor-specific reset types in PSCI
SYSTEM_RESET2 call.

Signed-off-by: Elliot Berman <quic_eberman at quicinc.com>
---
 Documentation/devicetree/bindings/arm/psci.yaml | 43 +++++++++++++++++++++++++
 1 file changed, 43 insertions(+)

diff --git a/Documentation/devicetree/bindings/arm/psci.yaml b/Documentation/devicetree/bindings/arm/psci.yaml
index cbb012e217ab..5e07c62fe5d7 100644
--- a/Documentation/devicetree/bindings/arm/psci.yaml
+++ b/Documentation/devicetree/bindings/arm/psci.yaml
@@ -98,6 +98,27 @@ properties:
       [1] Kernel documentation - ARM idle states bindings
         Documentation/devicetree/bindings/cpu/idle-states.yaml
 
+  reset-types:
+    type: object
+    $ref: /schemas/power/reset/reboot-mode.yaml#
+    unevaluatedProperties: false
+    properties:
+      # "mode-normal" is just SYSTEM_RESET
+      mode-normal: false
+    patternProperties:
+      "^mode-.*$":
+        minItems: 1
+        maxItems: 2
+        description: |
+          Describes a vendor-specific reset type. The string after "mode-"
+          maps a reboot mode to the parameters in the PSCI SYSTEM_RESET2 call.
+
+          Parameters are named mode-xxx = <type[, cookie]>, where xxx
+          is the name of the magic reboot mode, type is the lower 31 bits
+          of the reset_type, and, optionally, the cookie value. If the cookie
+          is not provided, it is defaulted to zero.
+          The 31st bit (vendor-resets) will be implicitly set by the driver.
+
 patternProperties:
   "^power-domain-":
     $ref: /schemas/power/power-domain.yaml#
@@ -137,6 +158,15 @@ allOf:
       required:
         - cpu_off
         - cpu_on
+  - if:
+      not:
+        properties:
+          compatible:
+            contains:
+              const: arm,psci-1.0
+    then:
+      properties:
+        reset-types: false
 
 additionalProperties: false
 
@@ -261,4 +291,17 @@ examples:
         domain-idle-states = <&CLUSTER_RET>, <&CLUSTER_PWRDN>;
       };
     };
+
+  - |+
+
+    // Case 5: SYSTEM_RESET2 vendor resets
+    psci {
+      compatible = "arm,psci-1.0";
+      method = "smc";
+
+      reset-types {
+        mode-edl = <0>;
+        mode-bootloader = <1 2>;
+      };
+    };
 ...

-- 
2.34.1




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