[RFC PATCH v3 1/2] arch: riscv: cpu: Add callback to init each core

[Leo Liang <ycliang@andestech.com>]

On Fri, Mar 26, 2021 at 05:03:54PM +0800, Green Wan wrote:
> On Fri, Mar 26, 2021 at 9:34 AM Sean Anderson <seanga2@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@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
> 
Hi Green,

Sorry for the late reply.
It seems that this v2 patch would fail to compile with but not limited to the following configs. 
	qemu-riscv[32|64]_defconfig, ae350_rv[32|64]_defconfig...

The v3 patch seems to fix the compile error, thanks!

Best regards,
Leo
> 
> >
> > --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;
> >