[RFC PATCH v2 1/2] arch: riscv: cpu: Add callback to init each core

[Green Wan]

On Fri, Mar 26, 2021 at 9:34 AM Sean Anderson <seanga2 at gmail.com> wrote:
>
> On 3/25/21 9:22 PM, Leo Liang wrote:
> > Hi Green,
> >
> > On Tue, Mar 23, 2021 at 01:35:38AM -0700, Green Wan wrote:
> >> Add a callback riscv_hart_early_init() to ./arch/riscv/cpu/start.S to
> >> allow different riscv hart perform setup code for each hart as early
> >> as possible. Since all the harts enter the calback, they must be able
> >> to run the same setup.
> >>
> >> Signed-off-by: Green Wan <green.wan at sifive.com>
> >> ---
> >>   arch/riscv/cpu/start.S | 5 +++++
> >>   arch/riscv/lib/spl.c   | 4 ++++
> >
> > This patch fails to compile for some defconfigs.
> > (CI result: https://dev.azure.com/ycliang-tw/u-boot-riscv/_build/results?buildId=15&view=results)
> >
> > Maybe we should come up with a better place to add this function.
>
> arch/riscv/cpu/cpu.c is a good candidate.

Hi Leo,

Thanks for reporting the result. Looks like the test doesn't use
"CONFIG_SPL_BUILD"? Thanks to Sean's suggestion, I will move dummy
riscv_hart_early_init() from ./arch/riscv/lib/spl.c to
./arch/riscv/cpu/cpu.c to create the next patch.

BTW, it's nice if you can share the .config file or CONFIG_* related
to CPU? I'd like to check around whether there are other possibilities
to break the code building? Thanks,

-- Green


>
> --Sean
>
> >
> > Best regards,
> > Leo
> >
> >>   2 files changed, 9 insertions(+)
> >>
> >> diff --git a/arch/riscv/cpu/start.S b/arch/riscv/cpu/start.S
> >> index 8589509e01..5c7d4da9e2 100644
> >> --- a/arch/riscv/cpu/start.S
> >> +++ b/arch/riscv/cpu/start.S
> >> @@ -117,6 +117,11 @@ call_board_init_f_0:
> >>      mv      sp, a0
> >>   #endif
> >>
> >> +#if CONFIG_IS_ENABLED(RISCV_MMODE)
> >> +call_riscv_hart_early_init:
> >> +    jal     riscv_hart_early_init
> >> +#endif
> >> +
> >>   #ifndef CONFIG_XIP
> >>      /*
> >>       * Pick hart to initialize global data and run U-Boot. The other harts
> >> diff --git a/arch/riscv/lib/spl.c b/arch/riscv/lib/spl.c
> >> index 8baee07bea..e5b1affbfc 100644
> >> --- a/arch/riscv/lib/spl.c
> >> +++ b/arch/riscv/lib/spl.c
> >> @@ -14,6 +14,10 @@
> >>
> >>   DECLARE_GLOBAL_DATA_PTR;
> >>
> >> +__weak void riscv_hart_early_init(void)
> >> +{
> >> +}
> >> +
> >>   __weak int spl_board_init_f(void)
> >>   {
> >>      return 0;
>