drm/i915: Fix clock readout when pipes are enabled w/o ports
authorVille Syrjälä <ville.syrjala@linux.intel.com>
Wed, 26 Aug 2015 16:39:18 +0000 (19:39 +0300)
committerDaniel Vetter <daniel.vetter@ffwll.ch>
Tue, 1 Sep 2015 10:02:09 +0000 (12:02 +0200)
commit0f64614dde172e4f4b2734a55091a4d307863cbb
treea181feda9850d4f264b439122326a13eb81f3080
parent30142273a3e83936fd7b45aa5339311a9295ca51
drm/i915: Fix clock readout when pipes are enabled w/o ports

The BIOS sometimes likes to enable pipes w/o any ports, at least on
older machines. Currently we fail to assign anything sensible to
crtc->hwmode.crtc_clock which leads to complaints from the vblank code.
Deal with active pipes w/o ports and assign something sensible to
crtc_clock in i9xx_get_pipe_config(). The encoder .get_config() will
override this if the port is enabled.

Gets rid of rest of these on my gen4:
[drm:drm_calc_timestamping_constants [drm]] *ERROR* crtc 24: Can't calculate constants, dotclock = 0!
[drm:i915_get_vblank_timestamp] crtc 1 is disabled

v2: Fill out crtc_clock already in i9xx_get_pipe_config() (Maarten)

Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
drivers/gpu/drm/i915/intel_display.c