Re: [PATCH] riscv: Fix IPI not initialized in riscv_cpu_setup()

[Yao Zi <me@ziyao.cc>]

On Fri, Sep 25, 2026 at 01:19:15PM +0300, Nikita Shubin wrote:
> Hi Yao Zi!
> 
> A shy ping on this patch.
> 
> Thanks !

Sorry for the delay.

> On Fri, 2026-09-04 at 08:20 +0200, Michal Simek wrote:
> > 
> > 
> > On 9/4/26 08:07, Nikita Shubin wrote:
> > > If riscv_cpu_setup() is skipped we end up with riscv_init_ipi() not
> > > being called.
> > > 
> > > But we still use riscv_send_ipi() in spl_invoke_opensbi(), so even
> > > if
> > > CONFIG_PHASE_CPU not set we still need init IPI and clear pending
> > > IPIs
> > > on harts.
> > > 
> > > Fixes: d8810e1d4f82 ("riscv: Skip riscv_cpu_setup() when CPU driver
> > > is disabled")
> > > Signed-off-by: Nikita Shubin <nikita.shubin@maquefel.me>
> > > ---
> > >   arch/riscv/cpu/cpu.c | 3 ++-
> > >   1 file changed, 2 insertions(+), 1 deletion(-)
> > > 
> > > diff --git a/arch/riscv/cpu/cpu.c b/arch/riscv/cpu/cpu.c
> > > index 3bec7c7cb6d..a65e6951384 100644
> > > --- a/arch/riscv/cpu/cpu.c
> > > +++ b/arch/riscv/cpu/cpu.c
> > > @@ -639,7 +639,7 @@ int riscv_cpu_setup(void)
> > >   	struct udevice *dev;
> > >   
> > >   	if (!CONFIG_IS_ENABLED(CPU))
> > > -		return 0;
> > > +		goto init_riscv_ipi;
> > >   
> > >   	uclass_find_first_device(UCLASS_CPU, &dev);
> > >   	if (!dev) {
> > > @@ -687,6 +687,7 @@ int riscv_cpu_setup(void)
> > >   #endif
> > >   	}
> > >   
> > > +init_riscv_ipi:
> > >   #if CONFIG_IS_ENABLED(SMP)
> > >   	ret = riscv_init_ipi();
> > >   	if (ret)
> > > 
> > > ---
> > > base-commit: cc557af4553382f6f50e3ed62b9577054e7bc54f
> > > change-id: 20260904-fix_skipped_ipi_init-aa5575f55bc4
> > > 
> > > Best regards,
> > 
> > There are 2 other approaches how to do it in the code but it is up to
> > maintainer 
> > to decide. No issue from my side to solve it via goto. Obviously one
> > big if 
> > (CONFIG_IS_ENABLED(CPU)) is another one. Or move it to own function.
> > 
> > Anyway
> > Acked-by: Michal Simek <michal.simek@amd.com>

I think it's likely a bad idea to have IPI stuff in riscv_cpu_setup(),
but this fix itself is okay. I should have noticed it when reviewing.

Reviewed-by: Yao Zi <me@ziyao.cc>

However, I'm RISC-V's reviewer instead of maintainer, so I couldn't pick
the patch for you though.

> > Thanks,
> > Michal

Best regards,
Yao Zi