On Sat, 27 Jul 2019, Anup Patel wrote: > > -----Original Message----- > > From: Paul Walmsley <paul.walms...@sifive.com> > > Sent: Saturday, July 27, 2019 5:00 AM > > > > On Fri, 26 Jul 2019, Atish Patra wrote: > > > > > On 7/26/19 1:47 PM, Paul Walmsley wrote: > > > > On Fri, 26 Jul 2019, Atish Patra wrote: > > > > > > > > > As per riscv specification, ISA naming strings are case > > > > > insensitive. However, currently only lower case strings are parsed > > > > > during cpu procfs. > > > > > > > > > > Support parsing of upper case letters as well. > > > > > > > > > > Signed-off-by: Atish Patra <atish.pa...@wdc.com> > > > > > > > > Is there a use case that's driving this, or > > > > > > Currently, we use all lower case isa string in kvmtool. But somebody > > > can have uppercase letters in future as spec allows it. > > > > > > > > > can we just say, "use > > > > lowercase letters" and leave it at that? > > > > > > > > > > In that case, it will not comply with RISC-V spec. Is that okay ? > > > > I think that section of the specification is mostly concerned with someone > > trying to define "f" as a different extension than "F", or something like > > that. > > I'm not sure that it imposes any constraint that software must accept both > > upper and lower case ISA strings. > > > > What gives me pause here is that this winds up impacting DT schema > > validation: > > > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Docu > > mentation/devicetree/bindings/riscv/cpus.yaml#n41 > > If 'f' and 'F' mean same extension as-per RISC-V spec then software should > also > interpret it that way hence this patch.
The list of valid RISC-V ISA strings is already constrained by the DT schema to be all lowercase. Anything else would violate the schema. I'd take a patch that would pr_warn() or a BUG() if any uppercase letters were found in the riscv,isa DT property, though, in case the developer skipped the DT schema validator. - Paul
