Commit 7ad25d48 authored Jan 17, 2014 by Paulo Zanoni Committed by Daniel Vetter Feb 12, 2014

drm/i915: WARN in case we're enabling the pipe and it's enabled



... and QUIRK_PIPEA_FORCE is not present.

I initially thought that case was impossible and just added a WARN on
it, but then I was told this case is possible due to
QUIRK_PIPEA_FORCE. So let's add a WARN that serves two purposes:
  - tell us in case we have done something wrong;
  - document the only case where we expect this.

Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

parent e1fdc473

drivers/gpu/drm/i915/intel_display.c

+4 −1

Original line number	Diff line number	Diff line
		@@ -1793,8 +1793,11 @@ static void intel_enable_pipe(struct intel_crtc *crtc)

		reg = PIPECONF(cpu_transcoder);
		val = I915_READ(reg);
		if (val & PIPECONF_ENABLE)
		if (val & PIPECONF_ENABLE) {
		WARN_ON(!(pipe == PIPE_A &&
		dev_priv->quirks & QUIRK_PIPEA_FORCE));
		return;
		}

		I915_WRITE(reg, val \| PIPECONF_ENABLE);
		POSTING_READ(reg);