drm/i915: Fix divide by zero on watermark update

Fix divide by zero if we end up updating the watermarks
with zero dotclock.

This is a stop gap measure to allow module load in cases
where our state keeping fails.

v2: WARN_ON added (Paulo)

Cc: Paulo Zanoni <przanoni@gmail.com>
Cc: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-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>
This commit is contained in:
Mika Kuoppala 2015-07-16 19:36:51 +03:00 committed by Daniel Vetter
parent 264954811a
commit 661abfc028
1 changed files with 3 additions and 1 deletions

View File

@ -3316,8 +3316,10 @@ skl_compute_linetime_wm(struct drm_crtc *crtc, struct skl_pipe_wm_parameters *p)
if (!to_intel_crtc(crtc)->active)
return 0;
return DIV_ROUND_UP(8 * p->pipe_htotal * 1000, p->pixel_rate);
if (WARN_ON(p->pixel_rate == 0))
return 0;
return DIV_ROUND_UP(8 * p->pipe_htotal * 1000, p->pixel_rate);
}
static void skl_compute_transition_wm(struct drm_crtc *crtc,