From 7ad25d488faf2622d5c1c3c04e42e8efe9539da0 Mon Sep 17 00:00:00 2001 From: Paulo Zanoni Date: Fri, 17 Jan 2014 13:51:13 -0200 Subject: [PATCH] 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 Reviewed-by: Damien Lespiau Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/intel_display.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index b040bd43bfd7..43b4281daf25 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -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); -- 2.20.1