Re: [PATCH v7 08/15] drm/i915/cmtg: Add a hook to make eDP transcoder secondary

["Ville Syrjälä" <ville.syrjala@linux.intel.com>]

On Tue, May 26, 2026 at 07:08:04PM +0530, Animesh Manna wrote:
> Program DDI_FUNC_CTL2 to configure the eDP transcoder as secondary
> to the CMTG transcoder.
> 
> v2:
> - Update commit header to be more clear. [Uma]
> 
> Reviewed-by: Uma Shankar <uma.shankar@intel.com>
> Signed-off-by: Animesh Manna <animesh.manna@intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_cmtg.c | 13 +++++++++++++
>  drivers/gpu/drm/i915/display/intel_cmtg.h |  1 +
>  2 files changed, 14 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_cmtg.c b/drivers/gpu/drm/i915/display/intel_cmtg.c
> index 63e430f7e63b..34715280d65d 100644
> --- a/drivers/gpu/drm/i915/display/intel_cmtg.c
> +++ b/drivers/gpu/drm/i915/display/intel_cmtg.c
> @@ -359,3 +359,16 @@ void intel_cmtg_enable_sync(const struct intel_crtc_state *crtc_state)
>  			 transcoder_name(cpu_transcoder));
>  	}
>  }
> +
> +void intel_cmtg_enable_ddi(const struct intel_crtc_state *crtc_state)
> +{
> +	struct intel_display *display = to_intel_display(crtc_state);
> +	enum transcoder cpu_transcoder = crtc_state->cpu_transcoder;
> +
> +	if (!intel_cmtg_is_allowed(crtc_state))
> +		return;
> +
> +	intel_de_rmw(display, TRANS_DDI_FUNC_CTL2(display, cpu_transcoder), 0, CMTG_SECONDARY_MODE);

We already have a place where we configure TRANS_DDI_FUNC_CTL2.
Why is this not there?

> +
> +	drm_dbg_kms(display->drm, "CMTG: %s enabled\n", transcoder_name(cpu_transcoder));
> +}
> diff --git a/drivers/gpu/drm/i915/display/intel_cmtg.h b/drivers/gpu/drm/i915/display/intel_cmtg.h
> index 64ff6a19948a..12abbafa7d08 100644
> --- a/drivers/gpu/drm/i915/display/intel_cmtg.h
> +++ b/drivers/gpu/drm/i915/display/intel_cmtg.h
> @@ -11,6 +11,7 @@
>  struct intel_display;
>  struct intel_crtc_state;
>  
> +void intel_cmtg_enable_ddi(const struct intel_crtc_state *crtc_state);
>  void intel_cmtg_enable_sync(const struct intel_crtc_state *crtc_state);
>  void intel_cmtg_set_m_n(const struct intel_crtc_state *crtc_state);
>  void intel_cmtg_set_vrr_timings(const struct intel_crtc_state *crtc_state);
> -- 
> 2.29.0

-- 
Ville Syrjälä
Intel