From b8d481671703c4ba24bb250a99225e0e3d8aedac Mon Sep 17 00:00:00 2001 From: Yong-Xuan Wang Date: Fri, 26 Jul 2024 16:49:27 +0800 Subject: [PATCH] dt-bindings: riscv: Add Svade and Svadu Entries Add entries for the Svade and Svadu extensions to the riscv,isa-extensions property. Signed-off-by: Yong-Xuan Wang Acked-by: Conor Dooley Reviewed-by: Alexandre Ghiti Reviewed-by: Samuel Holland Acked-by: Palmer Dabbelt Link: https://lore.kernel.org/r/20240726084931.28924-3-yongxuan.wang@sifive.com Signed-off-by: Anup Patel --- .../devicetree/bindings/riscv/extensions.yaml | 28 +++++++++++++++++++ 1 file changed, 28 insertions(+) diff --git a/Documentation/devicetree/bindings/riscv/extensions.yaml b/Documentation/devicetree/bindings/riscv/extensions.yaml index 2cf2026cff574..c5a8d154bb24e 100644 --- a/Documentation/devicetree/bindings/riscv/extensions.yaml +++ b/Documentation/devicetree/bindings/riscv/extensions.yaml @@ -153,6 +153,34 @@ properties: ratified at commit 3f9ed34 ("Add ability to manually trigger workflow. (#2)") of riscv-time-compare. + - const: svade + description: | + The standard Svade supervisor-level extension for SW-managed PTE A/D + bit updates as ratified in the 20240213 version of the privileged + ISA specification. + + Both Svade and Svadu extensions control the hardware behavior when + the PTE A/D bits need to be set. The default behavior for the four + possible combinations of these extensions in the device tree are: + 1) Neither Svade nor Svadu present in DT => It is technically + unknown whether the platform uses Svade or Svadu. Supervisor + software should be prepared to handle either hardware updating + of the PTE A/D bits or page faults when they need updated. + 2) Only Svade present in DT => Supervisor must assume Svade to be + always enabled. + 3) Only Svadu present in DT => Supervisor must assume Svadu to be + always enabled. + 4) Both Svade and Svadu present in DT => Supervisor must assume + Svadu turned-off at boot time. To use Svadu, supervisor must + explicitly enable it using the SBI FWFT extension. + + - const: svadu + description: | + The standard Svadu supervisor-level extension for hardware updating + of PTE A/D bits as ratified in the 20240528 version of the + privileged ISA specification. Please refer to Svade dt-binding + description for more details. + - const: svinval description: The standard Svinval supervisor-level extension for fine-grained