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

[Rick Chen]

> 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
> 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 at 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: Rick Chen <rick at andestech.com>