[PATCH v6 13/25] x86: mp: Allow running functions on multiple CPUs

[Bin Meng]

On Fri, Jul 17, 2020 at 10:49 PM Simon Glass <sjg at chromium.org> wrote:
>
> Add a way to run a function on a selection of CPUs. This supports either
> a single CPU, all CPUs, just the main CPU or just the 'APs', in Intel
> terminology.
>
> It works by writing into a mailbox and then waiting for the CPUs to notice
> it, take action and indicate they are done.
>
> When SMP is not yet enabled, this just calls the function on the main CPU.
>
> Signed-off-by: Simon Glass <sjg at chromium.org>
> Reviewed-by: Wolfgang Wallner <wolfgang.wallner at br-automation.com>
> ---
>
> (no changes since v4)
>
> Changes in v4:
> - Only enable this feature of CONFIG_SMP_AP_WORK is enabled
> - Allow running on the BSP if SMP is not enabled
>
> Changes in v3:
> - Add a comment to run_ap_work()
> - Rename flag to GD_FLG_SMP_READY
> - Update the comment for run_ap_work() to explain logical_cpu_number
> - Clarify meaning of @cpu_select in mp_run_on_cpus() comment
>
>  arch/x86/cpu/mp_init.c    | 107 +++++++++++++++++++++++++++++++++++---
>  arch/x86/include/asm/mp.h |  33 ++++++++++++
>  2 files changed, 134 insertions(+), 6 deletions(-)
>

Reviewed-by: Bin Meng <bmeng.cn at gmail.com>