On Wed, Mar 18, 2020 at 8:14 PM Bin Meng bmeng.cn@gmail.com wrote:
On Thu, Mar 19, 2020 at 11:10 AM Bin Meng bmeng.cn@gmail.com wrote:
On Wed, Mar 18, 2020 at 5:19 AM Atish Patra atish.patra@wdc.com wrote:
Linux booting protocol mandates that register "a0" contains the hartid. However, U-boot can not pass the hartid via a0 during via standard UEFI
nits: U-Boot
remove "during" ?
protocol. DT nodes are commonly used to pass such information to the OS.
Add a DT node under chosen node to indicate the boot hartid. EFI stub in Linux kernel will parse this node and pass it to the real kernel in "a0" before jumping to it.
Signed-off-by: Atish Patra atish.patra@wdc.com Reviewed-by: Rick Chen rick@andestech.com
arch/riscv/lib/bootm.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+)
diff --git a/arch/riscv/lib/bootm.c b/arch/riscv/lib/bootm.c index fad16901c5f2..f927694ae32f 100644 --- a/arch/riscv/lib/bootm.c +++ b/arch/riscv/lib/bootm.c @@ -28,6 +28,28 @@ __weak void board_quiesce_devices(void)
int arch_fixup_fdt(void *blob) {
One additional note, do have need to guard the "boot-hartid" fix-up with
#ifdef CONFIG_EFI_LOADER
#endif
Good point. Thanks I will add it.
?
u32 size;int chosen_offset, err;size = fdt_totalsize(blob);err = fdt_open_into(blob, blob, size + 32);if (err < 0) {printf("Device Tree can't be expanded to accommodate new node");return -1;return err
Sure.
}chosen_offset = fdt_path_offset(blob, "/chosen");if (chosen_offset < 0) {err = fdt_add_subnode(blob, 0, "chosen");if (err < 0) {printf("chosen node can not be added\n");return -1;return err
Sure.
}}/* Overwrite the boot-hartid as U-Boot is the last state BL */typo: stage
fdt_setprop_u32(blob, chosen_offset, "boot-hartid",gd->arch.boot_hart);return 0;}
--
Regards, Bin
I will address all other typos as well.