Re: [PATCH v3 01/14] RISC-V: fix funct4 definition for c.jalr in parse_asm.h

Andrew Jones
2022-12-01T17:05:59Z

On Thu, Dec 01, 2022 at 06:00:23PM +0100, Andrew Jones wrote:
> On Wed, Nov 30, 2022 at 11:56:01PM +0100, Heiko Stuebner wrote:
> > From: Heiko Stuebner <heiko.stuebner@vrull.eu>
> >
> > The opcode definition for c.jalr is
> > c.jalr c_rs1_n0 1..0=2 15..13=4 12=1 6..2=0
> >
> > This means funct4 consisting of bit [15:12] is 1001b, so the value is 0x9.
>
> I presume kgdb c.jalr stepping was broken before this patch and, if so,
> then we should add a comment stating that and also
>
> Fixes: edde5584c7ab ("riscv: Add SW single-step support for KDB")
>
> and maybe to help keep me motivated :-)
>
> Reported-by: Andrew Jones <ajones@ventanamicro.com>
>

Oh, and,

Reviewed-by: Andrew Jones <ajones@ventanamicro.com>

> Thanks,
> drew
>
> >
> > Signed-off-by: Heiko Stuebner <heiko.stuebner@vrull.eu>
> > ---
> > arch/riscv/include/asm/parse_asm.h | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/arch/riscv/include/asm/parse_asm.h b/arch/riscv/include/asm/parse_asm.h
> > index f36368de839f..7fee806805c1 100644
> > --- a/arch/riscv/include/asm/parse_asm.h
> > +++ b/arch/riscv/include/asm/parse_asm.h
> > @@ -125,7 +125,7 @@
> > #define FUNCT3_C_J 0xa000
> > #define FUNCT3_C_JAL 0x2000
> > #define FUNCT4_C_JR 0x8000
> > -#define FUNCT4_C_JALR 0xf000
> > +#define FUNCT4_C_JALR 0x9000
> >
> > #define FUNCT12_SRET 0x10200000
> >
> > --
> > 2.35.1
> >