Re: [PATCH] RISC-V: Allow both Zmmul and M
On Fri, Jul 15, 2022 at 4:13 AM Palmer Dabbelt wrote: > > We got to talking about how Zmmul and M interact with each other > https://github.com/riscv/riscv-isa-manual/issues/869 , and it turns out > that QEMU's behavior is slightly wrong: having Zmmul and M is a legal > combination, it just means that the multiplication instructions are > supported even when M is disabled at runtime via misa. > > This just stops overriding M from Zmmul, with that the other checks for > the multiplication instructions work as per the ISA. > > Signed-off-by: Palmer Dabbelt Thanks! Applied to riscv-to-apply.next Alistair > --- > target/riscv/cpu.c | 5 - > 1 file changed, 5 deletions(-) > > diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c > index db2b8e4d30..cab74faaca 100644 > --- a/target/riscv/cpu.c > +++ b/target/riscv/cpu.c > @@ -709,11 +709,6 @@ static void riscv_cpu_realize(DeviceState *dev, Error > **errp) > cpu->cfg.ext_ifencei = true; > } > > -if (cpu->cfg.ext_m && cpu->cfg.ext_zmmul) { > -warn_report("Zmmul will override M"); > -cpu->cfg.ext_m = false; > -} > - > if (cpu->cfg.ext_i && cpu->cfg.ext_e) { > error_setg(errp, > "I and E extensions are incompatible"); > -- > 2.34.1 > >
Re: [PATCH] RISC-V: Allow both Zmmul and M
On Fri, Jul 15, 2022 at 4:13 AM Palmer Dabbelt wrote: > > We got to talking about how Zmmul and M interact with each other > https://github.com/riscv/riscv-isa-manual/issues/869 , and it turns out > that QEMU's behavior is slightly wrong: having Zmmul and M is a legal > combination, it just means that the multiplication instructions are > supported even when M is disabled at runtime via misa. > > This just stops overriding M from Zmmul, with that the other checks for > the multiplication instructions work as per the ISA. > > Signed-off-by: Palmer Dabbelt Reviewed-by: Alistair Francis Alistair > --- > target/riscv/cpu.c | 5 - > 1 file changed, 5 deletions(-) > > diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c > index db2b8e4d30..cab74faaca 100644 > --- a/target/riscv/cpu.c > +++ b/target/riscv/cpu.c > @@ -709,11 +709,6 @@ static void riscv_cpu_realize(DeviceState *dev, Error > **errp) > cpu->cfg.ext_ifencei = true; > } > > -if (cpu->cfg.ext_m && cpu->cfg.ext_zmmul) { > -warn_report("Zmmul will override M"); > -cpu->cfg.ext_m = false; > -} > - > if (cpu->cfg.ext_i && cpu->cfg.ext_e) { > error_setg(errp, > "I and E extensions are incompatible"); > -- > 2.34.1 > >
[PATCH] RISC-V: Allow both Zmmul and M
We got to talking about how Zmmul and M interact with each other https://github.com/riscv/riscv-isa-manual/issues/869 , and it turns out that QEMU's behavior is slightly wrong: having Zmmul and M is a legal combination, it just means that the multiplication instructions are supported even when M is disabled at runtime via misa. This just stops overriding M from Zmmul, with that the other checks for the multiplication instructions work as per the ISA. Signed-off-by: Palmer Dabbelt --- target/riscv/cpu.c | 5 - 1 file changed, 5 deletions(-) diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c index db2b8e4d30..cab74faaca 100644 --- a/target/riscv/cpu.c +++ b/target/riscv/cpu.c @@ -709,11 +709,6 @@ static void riscv_cpu_realize(DeviceState *dev, Error **errp) cpu->cfg.ext_ifencei = true; } -if (cpu->cfg.ext_m && cpu->cfg.ext_zmmul) { -warn_report("Zmmul will override M"); -cpu->cfg.ext_m = false; -} - if (cpu->cfg.ext_i && cpu->cfg.ext_e) { error_setg(errp, "I and E extensions are incompatible"); -- 2.34.1