[Intel-gfx] [PATCH 34/58] drm/i915: ensure the force pipe A quirk is actually followed

[Jesse Barnes]

On Sun, 19 Aug 2012 21:12:51 +0200
Daniel Vetter <daniel.vetter at ffwll.ch> wrote:

> Many BIOSen forget to turn on the pipe A after resume (because they
> actually don't turn on anything), so we have to do that ourselves when
> sanitizing the hw state.
> 
> I've discovered this due to the recent addition of a pipe WARN that
> takes the force quirk into account.
> 
> v2: Actually try to enable the pipe with a proper configuration instead
> of simpyl switching it on with whatever random state the bios left it
> in after resume.
> 
> v3: Fixup rebase conflict - the load_detect functions have lost their
> encoder argument.
> 
> Signed-Off-by: Daniel Vetter <daniel.vetter at ffwll.ch>
> ---
>  drivers/gpu/drm/i915/intel_display.c | 36 ++++++++++++++++++++++++++++++++++++
>  1 file changed, 36 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> index 2cfb397..ab4fa7f 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -7602,6 +7602,33 @@ intel_connector_break_all_links(struct intel_connector *connector)
>  	connector->encoder->base.crtc = NULL;
>  }
>  
> +static void intel_enable_pipe_a(struct drm_device *dev)
> +{
> +	struct intel_connector *connector;
> +	struct drm_connector *crt = NULL;
> +	struct intel_load_detect_pipe load_detect_temp;
> +
> +	/* We can't just switch on the pipe A, we need to set things up with a
> +	 * proper mode and output configuration. As a gross hack, enable pipe A
> +	 * by enabling the load detect pipe once. */
> +	list_for_each_entry(connector,
> +			    &dev->mode_config.connector_list,
> +			    base.head) {
> +		if (connector->encoder->type == INTEL_OUTPUT_ANALOG) {
> +			crt = &connector->base;
> +			break;
> +		}
> +	}
> +
> +	if (!crt)
> +		return;
> +
> +	if (intel_get_load_detect_pipe(crt, NULL, &load_detect_temp))
> +		intel_release_load_detect_pipe(crt, &load_detect_temp);

Should we shout if this fails?  Other than that:
Reviewed-by: Jesse Barnes <jbarnes at virtuousgeek.org>

-- 
Jesse Barnes, Intel Open Source Technology Center