Commit b8d48167 authored by Yong-Xuan Wang's avatar Yong-Xuan Wang Committed by Anup Patel
Browse files

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: default avatarYong-Xuan Wang <yongxuan.wang@sifive.com>
Acked-by: default avatarConor Dooley <conor.dooley@microchip.com>
Reviewed-by: default avatarAlexandre Ghiti <alexghiti@rivosinc.com>
Reviewed-by: default avatarSamuel Holland <samuel.holland@sifive.com>
Acked-by: default avatarPalmer Dabbelt <palmer@rivosinc.com>
Link: https://lore.kernel.org/r/20240726084931.28924-3-yongxuan.wang@sifive.com


Signed-off-by: default avatarAnup Patel <anup@brainfault.org>
parent 94a7734d

Documentation/devicetree/bindings/riscv/extensions.yaml

+28 −0
Original line number Diff line number Diff line
@@ -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