On 11/04/2024 13:53, Conor Dooley wrote: > On Thu, Apr 11, 2024 at 11:08:21AM +0200, Clément Léger wrote: >>>> If we consider to have potentially broken isa string (ie extensions >>>> dependencies not correctly handled), then we'll need some way to >>>> validate this within the kernel. >>> >>> No, the DT passed to the kernel should be correct and we by and large we >>> should not have to do validation of it. What I meant above was writing >>> the binding so that something invalid will not pass dtbs_check. >> >> Acked, I was mainly answering Deepak question about dependencies wrt to >> using __RISCV_ISA_EXT_SUPERSET() which does not seems to be relevant >> since we expect a correct isa string to be passed. > > Ahh, okay. > >> But as you stated, DT >> validation clearly make sense. I think a lot of extensions strings would >> benefit such support (All the Zv* depends on V, etc). > > I think it is actually as simple something like this, which makes it > invalid to have "d" without "f": > > | diff --git a/Documentation/devicetree/bindings/riscv/extensions.yaml b/Documentation/devicetree/bindings/riscv/extensions.yaml > | index 468c646247aa..594828700cbe 100644 > | --- a/Documentation/devicetree/bindings/riscv/extensions.yaml > | +++ b/Documentation/devicetree/bindings/riscv/extensions.yaml > | @@ -484,5 +484,20 @@ properties: > | Registers in the AX45MP datasheet. > | https://www.andestech.com/wp-content/uploads/AX45MP-1C-Rev.-5.0.0-Datasheet.pdf > | > | +allOf: > | + - if: > | + properties: > | + riscv,isa-extensions: > | + contains: > | + const: "d" > | + not: > | + contains: > | + const: "f" > | + then: > | + properties: > | + riscv,isa-extensions: > | + false > | + > | + > | additionalProperties: true > | ... > > If you do have d without f, the checker will say: > cpu@2: riscv,isa-extensions: False schema does not allow ['i', 'm', 'a', 'd', 'c'] > > At least that's readable, even though not clear about what to do. I wish That looks really readable indeed but the messages that result from errors are not so informative. It tried playing with various constructs and found this one to yield a comprehensive message: +allOf: + - if: + properties: + riscv,isa-extensions: + contains: + const: zcf + not: + contains: + const: zca + then: + properties: + riscv,isa-extensions: + items: + anyOf: + - const: zca arch/riscv/boot/dts/allwinner/sun20i-d1-dongshan-nezha-stu.dtb: cpu@0: riscv,isa-extensions:10: 'anyOf' conditional failed, one must be fixed: 'zca' was expected from schema $id: http://devicetree.org/schemas/riscv/extensions.yaml Even though dt-bindings-check passed, not sure if this is totally a valid construct though... Thanks, Clément > the former could be said about the wall of text you get for /each/ > undocumented entry in the string.
