Re: [PATCH] drm/i915: disable sdvo pixel multiplier cross-check for HAS_PCH_SPLIT

[Daniel Vetter <daniel@ffwll.ch>]

On Wed, Jun 12, 2013 at 11:47:24AM +0200, Daniel Vetter wrote:
> We don't (yet) have proper pixel multiplier readout support on pch
> split platforms, so the cross check will naturally fail.
> 
> v2: Fix spelling in the comment, spotted by Ville.
> 
> v3: Since the ordering constraint is pretty tricky between the crtc
> get_pipe_config callback and the encoder->get_config callback add a
> few comments about it. Prompted by a discussion with Chris Wilson on
> irc about why this does work anywhere else than on i915g/gm.
> 
> Reported-by: Chris Wilson <chris@chris-wilson.co.uk>
> Cc: Chris Wilson <chris@chris-wilson.co.uk>
> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

Merged with Chris' irc-ack to dinq.
-Daniel

> ---
>  drivers/gpu/drm/i915/intel_drv.h  |  3 ++-
>  drivers/gpu/drm/i915/intel_sdvo.c | 11 +++++++++++
>  2 files changed, 13 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
> index 3363358..cf26fa8 100644
> --- a/drivers/gpu/drm/i915/intel_drv.h
> +++ b/drivers/gpu/drm/i915/intel_drv.h
> @@ -140,7 +140,8 @@ struct intel_encoder {
>  	 * it is connected to in the pipe parameter. */
>  	bool (*get_hw_state)(struct intel_encoder *, enum pipe *pipe);
>  	/* Reconstructs the equivalent mode flags for the current hardware
> -	 * state. */
> +	 * state. This must be called _after_ display->get_pipe_config has
> +	 * pre-filled the pipe config. */
>  	void (*get_config)(struct intel_encoder *,
>  			   struct intel_crtc_config *pipe_config);
>  	int crtc_mask;
> diff --git a/drivers/gpu/drm/i915/intel_sdvo.c b/drivers/gpu/drm/i915/intel_sdvo.c
> index a6c53b6..1327fa9 100644
> --- a/drivers/gpu/drm/i915/intel_sdvo.c
> +++ b/drivers/gpu/drm/i915/intel_sdvo.c
> @@ -1342,6 +1342,13 @@ static void intel_sdvo_get_config(struct intel_encoder *encoder,
>  
>  	pipe_config->adjusted_mode.flags |= flags;
>  
> +	/*
> +	 * pixel multiplier readout is tricky: Only on i915g/gm it is stored in
> +	 * the sdvo port register, on all other platforms it is part of the dpll
> +	 * state. Since the general pipe state readout happens before the
> +	 * encoder->get_config we so already have a valid pixel multplier on all
> +	 * other platfroms.
> +	 */
>  	if (IS_I915G(dev) || IS_I915GM(dev)) {
>  		sdvox = I915_READ(intel_sdvo->sdvo_reg);
>  		pipe_config->pixel_multiplier =
> @@ -1362,6 +1369,10 @@ static void intel_sdvo_get_config(struct intel_encoder *encoder,
>  		encoder_pixel_multiplier = 4;
>  		break;
>  	}
> +
> +	if(HAS_PCH_SPLIT(dev))
> +		return; /* no pixel multiplier readout support yet */
> +
>  	WARN(encoder_pixel_multiplier != pipe_config->pixel_multiplier,
>  	     "SDVO pixel multiplier mismatch, port: %i, encoder: %i\n",
>  	     pipe_config->pixel_multiplier, encoder_pixel_multiplier);
> -- 
> 1.7.11.7
> 

-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch