[PATCH] scmi: correctly configure MMU for SCMI buffer

[Etienne Carriere]

Hello Patrick,

On Tue, 16 Mar 2021 at 09:29, Patrick Delaunay
<patrick.delaunay at foss.st.com> wrote:
>
> Align the MMU area for SCMI shared buffer on section size;
> use the ALIGN macro in mmu_set_region_dcache_behaviour call.
>
> Since commit d877f8fd0f09 ("arm: provide a function for boards init
> code to modify MMU virtual-physical map") the parameter of
> mmu_set_region_dcache_behaviour need to be MMU_SECTION_SIZE
> aligned.
>
> Fixes: 240720e9052f ("firmware: scmi: mailbox/smt agent device")
> Signed-off-by: Patrick Delaunay <patrick.delaunay at foss.st.com>
> ---
>
>  drivers/firmware/scmi/smt.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/firmware/scmi/smt.c b/drivers/firmware/scmi/smt.c
> index d25478796a..3c41013bca 100644
> --- a/drivers/firmware/scmi/smt.c
> +++ b/drivers/firmware/scmi/smt.c
> @@ -54,8 +54,10 @@ int scmi_dt_get_smt_buffer(struct udevice *dev, struct scmi_smt *smt)
>
>  #ifdef CONFIG_ARM
>         if (dcache_status())
> -               mmu_set_region_dcache_behaviour((uintptr_t)smt->buf,
> -                                               smt->size, DCACHE_OFF);
> +               mmu_set_region_dcache_behaviour(ALIGN_DOWN((uintptr_t)smt->buf, MMU_SECTION_SIZE),
> +                                               ALIGN(smt->size, MMU_SECTION_SIZE),
> +                                               DCACHE_OFF);
> +
>  #endif
>
>         return 0;
> --
> 2.17.1
>

Reviewed-by: Etienne Carriere <etienne.carriere at linaro.org>

This indeed fixes the scmi smt driver.
Thanks Patrick.

Regards,
Etienne