[kvm-unit-tests PATCH 1/2] riscv: Allow SBI_CONSOLE with no uart in device tree

[Jesse Taube]

On Fri, Jun 13, 2025 at 12:53 AM Andrew Jones <andrew.jones at linux.dev> wrote:
>
> On Thu, Jun 12, 2025 at 01:07:47PM -0700, Jesse Taube wrote:
> > When CONFIG_SBI_CONSOLE is enabled and there is no uart defined in the
> > device tree kvm-unit-tests fails to start.
> >
> > Only check if uart exists in device tree if SBI_CONSOLE is false.
> >
> > Signed-off-by: Jesse Taube <jesse at rivosinc.com>
> > ---
> >  lib/riscv/io.c | 2 ++
> >  1 file changed, 2 insertions(+)
> >
> > diff --git a/lib/riscv/io.c b/lib/riscv/io.c
> > index fb40adb7..96a3c048 100644
> > --- a/lib/riscv/io.c
> > +++ b/lib/riscv/io.c
> > @@ -104,6 +104,7 @@ static void uart0_init_acpi(void)
> >
> >  void io_init(void)
> >  {
> > +#ifndef CONFIG_SBI_CONSOLE
> >       if (dt_available())
> >               uart0_init_fdt();
> >       else
> > @@ -114,6 +115,7 @@ void io_init(void)
> >                      "Found uart at %p, but early base is %p.\n",
> >                      uart0_base, UART_EARLY_BASE);
> >       }
> > +#endif
>
> Doesn't this generate uart0_init_fdt/acpi defined but not used types of
> warnings?

No, but it should have, I'll fix it.

> We need to put everything unused under the #ifndef
> CONFIG_SBI_CONSOLE, just as uart0_read/write already are. Alternatively,
> we can keep everything out of the #ifndef and export.

The problem is uart0_init_fdt panics if no compatible uart was found.

Thanks,
Jesse Taube
> void sbi_puts(const char *s);
> void uart0_puts(const char *s);
>
> then just have a single use of the #ifdef,
>
> void puts(const char *s)
> {
> #ifdef CONFIG_SBI_CONSOLE
>     sbi_puts(s);
> #else
>     uart0_puts(s);
> #endif
> }
>
> I think I like that better since it will ensure all code gets compile
> tested all the time and allow an SBI console using unit test to also
> access its uart if it has one, just because...
>
> Thanks,
> drew
>
>
> >  }
> >
> >  #ifdef CONFIG_SBI_CONSOLE
> > --
> > 2.43.0
> >
> >
> > --
> > kvm-riscv mailing list
> > kvm-riscv at lists.infradead.org
> > http://lists.infradead.org/mailman/listinfo/kvm-riscv