[PATCH 1/3] dt-bindings: riscv: Add Supm extension description

[Guodong Xu]

Add description for the Supm extension. Supm indicates support for pointer
masking in user mode. Supm is mandatory for RVA23S64.

The Supm extension is ratified in commit d70011dde6c2 ("Update to ratified
state") of riscv-j-extension.

Signed-off-by: Guodong Xu <guodong at riscstar.com>
---
 Documentation/devicetree/bindings/riscv/extensions.yaml | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/Documentation/devicetree/bindings/riscv/extensions.yaml b/Documentation/devicetree/bindings/riscv/extensions.yaml
index 4ffd61926505..1922dff03787 100644
--- a/Documentation/devicetree/bindings/riscv/extensions.yaml
+++ b/Documentation/devicetree/bindings/riscv/extensions.yaml
@@ -262,6 +262,23 @@ properties:
             ratified in RISC-V Profiles Version 1.0, with commit b1d806605f87
             ("Updated to ratified state.")
 
+        - const: supm
+          description: |
+            The standard Supm extension for pointer masking support in user
+            mode (U-mode) as ratified at commit d70011dde6c2 ("Update to
+            ratified state") of riscv-j-extension.
+
+            Supm represents a combination of underlying hardware capability
+            (Smnpm or Ssnpm), U-mode consumer privilege level, and M/S-mode
+            software configuration that enables pointer masking for U-mode.
+
+            DO NOT include this property in device trees targeting privileged
+            system software (S-mode or M-mode).
+
+            This property is only appropriate in device trees provided to
+            U-mode software where the next-higher-privilege-mode supports
+            Smnpm or Ssnpm and enables it for U-mode.
+
         - const: svade
           description: |
             The standard Svade supervisor-level extension for SW-managed PTE A/D

-- 
2.43.0