Re: [PATCH v8 1/1] drm/i915/display: Add no_psr_reason to PSR debugfs

[Sebastian Brzezinka <sebastian.brzezinka@intel.com>]

Hi Michał
On Thu Aug 28, 2025 at 10:49 AM UTC, Michał Grzelak wrote:
> There is no reason in debugfs why PSR has been disabled. Add
It might be useful to explain the motivation behind this feature.

> no_psr_reason field into struct intel_psr. Write the reason,
> e.g. PSR setup timing not met, into proper PSR debugfs file.
> Extend format of debugfs file to have reason when non-NULL.
> Ensure no_psr_reason is up-to-date or NULL by resetting it
> at the beginning of intel_psr_compute_config. Clean it when
> PSR is activated.
>
> Refactor intel_psr_post_plane_update to use no_psr_reason
> along keep_disabled.
It appears to be version 8. I think it would be helpful to include a changelog. 

>
> Signed-off-by: Michał Grzelak <michal.grzelak@intel.com>
> ---
>  .../drm/i915/display/intel_display_types.h    |  2 ++
>  drivers/gpu/drm/i915/display/intel_psr.c      | 21 +++++++++++++++----
>  2 files changed, 19 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h
> index fd9d2527889b..0f8332ce1aa0 100644
> --- a/drivers/gpu/drm/i915/display/intel_display_types.h
> +++ b/drivers/gpu/drm/i915/display/intel_display_types.h
> @@ -1687,6 +1687,8 @@ struct intel_psr {
>  	bool pkg_c_latency_used;
>  
>  	u8 active_non_psr_pipes;
> +
> +	const char *no_psr_reason;
Have you considered using an enum or another type instead of a char pointer?

-- 
Best regards,
Sebastian