From 35c95375f69ceec721fea67a0532bc17ceb5cf64 Mon Sep 17 00:00:00 2001 From: Daniel Vetter Date: Wed, 17 Jul 2013 06:55:04 +0200 Subject: [PATCH] drm/i915: Sanitize shared dpll state There seems to be no limit to the amount of gunk the firmware can leave behind. Some platforms leave pch dplls on which are not in active use at all. The example in the bug report is a Apple Macbook Pro. Note that this escape scrunity of the hw state checker until we've tried to use this enabled, but unused pll since we did only check for the inverse case of a in-used, but disabled pll. v2: Add a WARN in the pll state checker which would have caught this case. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=66952 Reported-and-tested-by: shui yangwei Reviewed-by: Chris Wilson Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/intel_display.c | 19 +++++++++++++++++-- 1 file changed, 17 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index c59335c..76b01c1 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -8314,6 +8314,8 @@ check_shared_dpll_state(struct drm_device *dev) pll->active, pll->refcount); WARN(pll->active && !pll->on, "pll in active use but not on in sw tracking\n"); + WARN(pll->on && !pll->active, + "pll in on but not on in use in sw tracking\n"); WARN(pll->on != active, "pll on state mismatch (expected %i, found %i)\n", pll->on, active); @@ -9814,8 +9816,8 @@ static void intel_modeset_readout_hw_state(struct drm_device *dev) } pll->refcount = pll->active; - DRM_DEBUG_KMS("%s hw state readout: refcount %i\n", - pll->name, pll->refcount); + DRM_DEBUG_KMS("%s hw state readout: refcount %i, on %i\n", + pll->name, pll->refcount, pll->on); } list_for_each_entry(encoder, &dev->mode_config.encoder_list, @@ -9866,6 +9868,7 @@ void intel_modeset_setup_hw_state(struct drm_device *dev, struct drm_plane *plane; struct intel_crtc *crtc; struct intel_encoder *encoder; + int i; intel_modeset_readout_hw_state(dev); @@ -9881,6 +9884,18 @@ void intel_modeset_setup_hw_state(struct drm_device *dev, intel_dump_pipe_config(crtc, &crtc->config, "[setup_hw_state]"); } + for (i = 0; i < dev_priv->num_shared_dpll; i++) { + struct intel_shared_dpll *pll = &dev_priv->shared_dplls[i]; + + if (!pll->on || pll->active) + continue; + + DRM_DEBUG_KMS("%s enabled but not in use, disabling\n", pll->name); + + pll->disable(dev_priv, pll); + pll->on = false; + } + if (force_restore) { /* * We need to use raw interfaces for restoring state to avoid -- 2.7.4