Re: [PATCH v2 3/7] riscv: Use a valid bit to ignore already-pending IPIs

On Mon, Sep 14, 2020 at 10:23 PM Sean Anderson seanga2@gmail.com wrote:

Some IPIs may already be pending when U-Boot is started. This could be a problem if a secondary hart tries to handle an IPI before the boot hart has initialized the IPI device.

This commit introduces a valid bit so secondary harts know when and IPI originates from U-boot, and it is safe to use the IPI API. The valid bit is

nits: U-Boot

initialized to 0 by board_init_f_init_reserve. Before this, secondary harts wait in wait_for_gd_init.

Signed-off-by: Sean Anderson seanga2@gmail.com

Changes in v2:

• Use a valid bit instead of addr to validate IPIs

arch/riscv/include/asm/smp.h | 7 +++++++ arch/riscv/lib/smp.c | 16 ++++++++++++++-- 2 files changed, 21 insertions(+), 2 deletions(-)

Reviewed-by: Bin Meng bin.meng@windriver.com