When watermark calculation was moved up to the atomic check phase, the code was updated to calculate based on in-flight atomic state rather than already-committed state. However the hsw_compute_linetime_wm() didn't get updated and continued to pull values out of the currently-committed CRTC state. On platforms that call this function (HSW/BDW only), this will cause problems when we go to enable the CRTC since we'll pull the current mode (off) rather than the mode we're calculating for and wind up with a divide by zero error. This was an oversight in commit: commit a28170f3389f4e42db95e595b0d86384a79de696 Author: Matt Roper <matthew.d.roper@xxxxxxxxx> Date: Thu Sep 24 15:53:16 2015 -0700 drm/i915: Calculate ILK-style watermarks during atomic check (v3) Signed-off-by: Matt Roper <matthew.d.roper@xxxxxxxxx> --- drivers/gpu/drm/i915/intel_pm.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index 612a8b4..9a31480 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -1998,14 +1998,19 @@ static void ilk_compute_wm_level(const struct drm_i915_private *dev_priv, } static uint32_t -hsw_compute_linetime_wm(struct drm_device *dev, struct drm_crtc *crtc) +hsw_compute_linetime_wm(struct drm_device *dev, + struct intel_crtc_state *cstate) { struct drm_i915_private *dev_priv = dev->dev_private; - struct intel_crtc *intel_crtc = to_intel_crtc(crtc); - const struct drm_display_mode *adjusted_mode = &intel_crtc->config->base.adjusted_mode; + const struct drm_display_mode *adjusted_mode = + &cstate->base.adjusted_mode; u32 linetime, ips_linetime; - if (!intel_crtc->active) + if (!cstate->base.active) + return 0; + if (WARN_ON(adjusted_mode->crtc_clock == 0)) + return 0; + if (WARN_ON(dev_priv->cdclk_freq == 0)) return 0; /* The WM are computed with base on how long it takes to fill a single @@ -2313,8 +2318,7 @@ static int ilk_compute_pipe_wm(struct intel_crtc *intel_crtc, pristate, sprstate, curstate, &pipe_wm->wm[0]); if (IS_HASWELL(dev) || IS_BROADWELL(dev)) - pipe_wm->linetime = hsw_compute_linetime_wm(dev, - &intel_crtc->base); + pipe_wm->linetime = hsw_compute_linetime_wm(dev, cstate); /* LP0 watermarks always use 1/2 DDB partitioning */ ilk_compute_wm_maximums(dev, 0, &config, INTEL_DDB_PART_1_2, &max); -- 2.1.4 _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx