[PATCH] event/cnxk: use WFE LDP loop for getwork routine

[Jerin Jacob]

On Fri, Jan 5, 2024 at 9:24 AM <pbhagavatula at marvell.com> wrote:
>
> From: Pavan Nikhilesh <pbhagavatula at marvell.com>
>
> Use WFE LDP loop while polling for GETWORK completion for better
> power savings.
> Disabled by default and can be enabled by setting
> `RTE_ARM_USE_WFE` to `true` in `config/arm/meson.build`
>
> Signed-off-by: Pavan Nikhilesh <pbhagavatula at marvell.com>
> ---
>  doc/guides/eventdevs/cnxk.rst     |  9 ++++++
>  drivers/event/cnxk/cn10k_worker.h | 52 +++++++++++++++++++++++++------
>  2 files changed, 52 insertions(+), 9 deletions(-)
>
> diff --git a/doc/guides/eventdevs/cnxk.rst b/doc/guides/eventdevs/cnxk.rst
> index cccb8a0304..d62c143c77 100644
> --- a/doc/guides/eventdevs/cnxk.rst
> +++ b/doc/guides/eventdevs/cnxk.rst
> @@ -198,6 +198,15 @@ Runtime Config Options
>
>      -a 0002:0e:00.0,tim_eclk_freq=122880000-1000000000-0
>
> +Power Savings on CN10K
> +----------------------
> +
> +ARM cores can additionally use WFE when polling for transactions on SSO bus
> +to save power i.e., in the event dequeue call ARM core can enter WFE and exit
> +when either work has been scheduled or dequeue timeout has reached.
> +This can be enabled by setting ``RTE_ARM_USE_WFE`` to ``true`` in
> +``config/arm/meson.build``.

+ ARM maintainers

IMO, Updating config/arm/meson.build for enabling RTE_ARM_USE_WFE,
needs to improved.
Could you push a patch for enabling via -D... or via -Dc_args=...