Re: [v1 PATCH 2/2] RISC-V: Consolidate isa correctness check

From: Atish Patra
Date: Wed Oct 09 2019 - 18:02:27 EST


On Tue, 2019-10-08 at 08:44 -0700, Christoph Hellwig wrote:
> > +int riscv_read_check_isa(struct device_node *node, const char
> > **isa)
> > +{
> > + u32 hart;
> > +
> > + if (of_property_read_u32(node, "reg", &hart)) {
> > + pr_warn("Found CPU without hart ID\n");
> > + return -ENODEV;
> > + }
> > +
> > + if (of_property_read_string(node, "riscv,isa", isa)) {
> > + pr_warn("CPU with hartid=%d has no \"riscv,isa\"
> > property\n",
> > + hart);
> > + return -ENODEV;
> > + }
> > +
> > + /*
> > + * Linux doesn't support rv32e or rv128i, and we only support
> > booting
> > + * kernels on harts with the same ISA that the kernel is
> > compiled for.
> > + */
> > +#if defined(CONFIG_32BIT)
> > + if (strncmp(*isa, "rv32i", 5) != 0)
> > + return -ENODEV;
> > +#elif defined(CONFIG_64BIT)
> > + if (strncmp(*isa, "rv64i", 5) != 0)
> > + return -ENODEV;
> > +#endif
>
> Using IS_ENABLED here would clean the checks up a bit.
>
> > diff --git a/arch/riscv/kernel/cpufeature.c
> > b/arch/riscv/kernel/cpufeature.c
> > index b1ade9a49347..eaad5aa07403 100644
> > --- a/arch/riscv/kernel/cpufeature.c
> > +++ b/arch/riscv/kernel/cpufeature.c
> > @@ -38,10 +38,8 @@ void riscv_fill_hwcap(void)
> > if (riscv_of_processor_hartid(node) < 0)
> > continue;
> >
> > - if (of_property_read_string(node, "riscv,isa", &isa)) {
> > - pr_warn("Unable to find \"riscv,isa\"
> > devicetree entry\n");
> > + if (riscv_read_check_isa(node, &isa) < 0)
> > continue;
>
> Do we really get rid of warnings if we didn't find anything proper?

Ok. Added back the warnings and IS_ENABLED in v2.

--
Regards,
Atish