[PATCH v6 4/8] drm/i915/lobf: Update lobf if any change in dependent parameters

[Hogander, Jouni]

On Thu, 2025-03-20 at 00:45 +0530, Animesh Manna wrote:
> For every commit the dependent condition for LOBF is checked
> and accordingly update has_lobf flag which will be used
> to update the ALPM_CTL register during commit.
> 
> v1: Initial version.
> v2: Avoid reading h/w register without has_lobf check. [Jani]
> v3: Update LOBF in post plane update instead of separate function.
> [Jouni]
> 
> Signed-off-by: Animesh Manna <animesh.manna at intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_alpm.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_alpm.c
> b/drivers/gpu/drm/i915/display/intel_alpm.c
> index c2862888466f..5df1253a6b6c 100644
> --- a/drivers/gpu/drm/i915/display/intel_alpm.c
> +++ b/drivers/gpu/drm/i915/display/intel_alpm.c
> @@ -378,9 +378,12 @@ void intel_alpm_post_plane_update(struct
> intel_atomic_state *state,
>  	struct intel_display *display = to_intel_display(state);
>  	const struct intel_crtc_state *crtc_state =
>  		intel_atomic_get_new_crtc_state(state, crtc);
> +	const struct intel_crtc_state *old_crtc_state =
> +		intel_atomic_get_old_crtc_state(state, crtc);
>  	struct intel_encoder *encoder;
>  
> -	if (!crtc_state->has_lobf && !crtc_state->has_psr)
> +	if (!crtc_state->has_lobf && !crtc_state->has_psr &&
> +	    !old_crtc_state->has_lobf)

I don't really understand this change? Where lobf is disabled when 
has_lobf is false?

BR,

Jouni Högander
>  		return;
>  
>  	for_each_intel_encoder_mask(display->drm, encoder,