Add a callback harts_early_init() to start.S to allow different riscv hart perform setup code for each hart as early as possible. Since all the harts enter the callback, they must be able to run the same setup.

Signed-off-by: Green Wan green.wan@sifive.com Reviewed-by: Rick Chen rick@andestech.com Reviewed-by: Bin Meng bmeng.cn@gmail.com --- arch/riscv/cpu/cpu.c | 11 +++++++++++ arch/riscv/cpu/start.S | 4 ++++ 2 files changed, 15 insertions(+)

diff --git a/arch/riscv/cpu/cpu.c b/arch/riscv/cpu/cpu.c index 85592f5bee..296e458db4 100644 --- a/arch/riscv/cpu/cpu.c +++ b/arch/riscv/cpu/cpu.c @@ -140,3 +140,14 @@ int arch_early_init_r(void) { return riscv_cpu_probe(); } + +/** + * harts_early_init() - A callback function called by start.S to configure + * feature settings of each hart. + * + * In a multi-core system, memory access shall be careful here, it shall + * take care of race conditions. + */ +__weak void harts_early_init(void) +{ +} diff --git a/arch/riscv/cpu/start.S b/arch/riscv/cpu/start.S index 8589509e01..308b0a97a5 100644 --- a/arch/riscv/cpu/start.S +++ b/arch/riscv/cpu/start.S @@ -117,6 +117,10 @@ call_board_init_f_0: mv sp, a0 #endif

+ /* Configure proprietary settings and customized CSRs of harts */ +call_harts_early_init: + jal harts_early_init + #ifndef CONFIG_XIP /* * Pick hart to initialize global data and run U-Boot. The other harts