Re: [PATCH v3 5/5] dt-bindings: Update the riscv,isa string description
From: Atish Patra
Date: Thu Aug 01 2019 - 19:07:44 EST
On Thu, 2019-08-01 at 09:50 -0600, Rob Herring wrote:
> On Wed, Jul 31, 2019 at 6:58 PM Atish Patra <atish.patra@xxxxxxx>
> wrote:
> > Since the RISC-V specification states that ISA description strings
> > are
> > case-insensitive, there's no functional difference between mixed-
> > case,
> > upper-case, and lower-case ISA strings. Thus, to simplify parsing,
> > specify that the letters present in "riscv,isa" must be all
> > lowercase.
> >
> > Suggested-by: Paul Walmsley <paul.walmsley@xxxxxxxxxx>
> > Signed-off-by: Atish Patra <atish.patra@xxxxxxx>
> > ---
> > Documentation/devicetree/bindings/riscv/cpus.yaml | 4 +++-
> > 1 file changed, 3 insertions(+), 1 deletion(-)
> >
> > diff --git a/Documentation/devicetree/bindings/riscv/cpus.yaml
> > b/Documentation/devicetree/bindings/riscv/cpus.yaml
> > index c899111aa5e3..4f0acb00185a 100644
> > --- a/Documentation/devicetree/bindings/riscv/cpus.yaml
> > +++ b/Documentation/devicetree/bindings/riscv/cpus.yaml
> > @@ -46,10 +46,12 @@ properties:
> > - rv64imafdc
> > description:
> > Identifies the specific RISC-V instruction set architecture
> > - supported by the hart. These are documented in the RISC-V
> > + supported by the hart. These are documented in the RISC-V
> > User-Level ISA document, available from
> > https://riscv.org/specifications/
> >
> > + Letters in the riscv,isa string must be all lowercase.
> > +
>
> The schemas are case sensitive this looks pretty pointless without
> the
> context of the commit msg. Can you prefix with 'While the
> specification is case insensitive, "
>
Sure. How about this ?
"While the above isa strings in ISA specification are case insensitive,
letters in the riscv,isa string must be all lowercase to simplify
parsing."
> For some background, FDT generally always has been case sensitive too
> (dtc won't merge/override nodes/properties with differing case). It's
> really only some older true OF systems that were case insensitive.
> The
> kernel had a mixture of case sensitive and insensitive comparisons
> somewhat depending on the arch and whether of_prop_cmp/of_node_cmp or
> str*cmp functions were used. There's been a lot of clean-up and now
> most comparisons are case sensitive with only Sparc having some
> deviation.
>
> Rob
--
Regards,
Atish