Re: [PATCH] drm/i915: Adding debug code for dp_m2_n2 in crtc_config

[Daniel Vetter <daniel@ffwll.ch>]

On Fri, Apr 11, 2014 at 05:01:20PM +0530, Vandana Kannan wrote:
> Adding relevant read out comparison code, in check_crtc_state, for the new
> member of crtc_config, dp_m2_n2, which was introduced to store link_m_n
> values for a DP downclock mode (if available). Suggested by Daniel.
> 
> Signed-off-by: Vandana Kannan <vandana.kannan@intel.com>
> Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
> ---
>  drivers/gpu/drm/i915/intel_display.c | 15 +++++++++++++++
>  1 file changed, 15 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> index 1af1d14..36fc034 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -9199,6 +9199,15 @@ static void intel_dump_pipe_config(struct intel_crtc *crtc,
>  		      pipe_config->dp_m_n.gmch_m, pipe_config->dp_m_n.gmch_n,
>  		      pipe_config->dp_m_n.link_m, pipe_config->dp_m_n.link_n,
>  		      pipe_config->dp_m_n.tu);
> +
> +	DRM_DEBUG_KMS("dp: %i, gmch_m2: %u, gmch_n2: %u, link_m2: %u, link_n2: %u, tu2: %u\n",
> +		      pipe_config->has_dp_encoder,
> +		      pipe_config->dp_m2_n2.gmch_m,
> +		      pipe_config->dp_m2_n2.gmch_n,
> +		      pipe_config->dp_m2_n2.link_m,
> +		      pipe_config->dp_m2_n2.link_n,
> +		      pipe_config->dp_m2_n2.tu);
> +
>  	DRM_DEBUG_KMS("requested mode:\n");
>  	drm_mode_debug_printmodeline(&pipe_config->requested_mode);
>  	DRM_DEBUG_KMS("adjusted mode:\n");
> @@ -9619,6 +9628,12 @@ intel_pipe_config_compare(struct drm_device *dev,
>  	PIPE_CONF_CHECK_I(dp_m_n.link_n);
>  	PIPE_CONF_CHECK_I(dp_m_n.tu);
>  
> +	PIPE_CONF_CHECK_I(dp_m2_n2.gmch_m);
> +	PIPE_CONF_CHECK_I(dp_m2_n2.gmch_n);
> +	PIPE_CONF_CHECK_I(dp_m2_n2.link_m);
> +	PIPE_CONF_CHECK_I(dp_m2_n2.link_n);
> +	PIPE_CONF_CHECK_I(dp_m2_n2.tu);
> +
>  	PIPE_CONF_CHECK_I(adjusted_mode.crtc_hdisplay);
>  	PIPE_CONF_CHECK_I(adjusted_mode.crtc_htotal);
>  	PIPE_CONF_CHECK_I(adjusted_mode.crtc_hblank_start);


Either I'm missing something or your patch lacks state readout support for
pipe_config->dp_m2_n2. It /should/ result in piles of WARNING backtraces
when you run this. Or you've based this on an Android tree which has the
state cross checker disabled. I'm confused.
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch