This patch replaces the locking from the downclock routines with an assert to ensure the registers are indeed unlocked. Without this patch, pre-SNB devices would lock the registers when downclocking which would cause a WARNING on suspend/resume with downclocking enabled.
Note: To hit this bug, you need to have lvds downclocking enabled. Signed-off-by: Sean Paul <[email protected]> --- drivers/gpu/drm/i915/intel_display.c | 14 ++------------ 1 files changed, 2 insertions(+), 12 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index ebe71ed..33ef4f3 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -6968,9 +6968,7 @@ static void intel_increase_pllclock(struct drm_crtc *crtc) if (!HAS_PIPE_CXSR(dev) && (dpll & DISPLAY_RATE_SELECT_FPA1)) { DRM_DEBUG_DRIVER("upclocking LVDS\n"); - /* Unlock panel regs */ - I915_WRITE(PP_CONTROL, - I915_READ(PP_CONTROL) | PANEL_UNLOCK_REGS); + assert_panel_unlocked(dev_priv, pipe); dpll &= ~DISPLAY_RATE_SELECT_FPA1; I915_WRITE(dpll_reg, dpll); @@ -6979,9 +6977,6 @@ static void intel_increase_pllclock(struct drm_crtc *crtc) dpll = I915_READ(dpll_reg); if (dpll & DISPLAY_RATE_SELECT_FPA1) DRM_DEBUG_DRIVER("failed to upclock LVDS!\n"); - - /* ...and lock them again */ - I915_WRITE(PP_CONTROL, I915_READ(PP_CONTROL) & 0x3); } /* Schedule downclock */ @@ -7011,9 +7006,7 @@ static void intel_decrease_pllclock(struct drm_crtc *crtc) if (!HAS_PIPE_CXSR(dev) && intel_crtc->lowfreq_avail) { DRM_DEBUG_DRIVER("downclocking LVDS\n"); - /* Unlock panel regs */ - I915_WRITE(PP_CONTROL, I915_READ(PP_CONTROL) | - PANEL_UNLOCK_REGS); + assert_panel_unlocked(dev_priv, pipe); dpll |= DISPLAY_RATE_SELECT_FPA1; I915_WRITE(dpll_reg, dpll); @@ -7021,9 +7014,6 @@ static void intel_decrease_pllclock(struct drm_crtc *crtc) dpll = I915_READ(dpll_reg); if (!(dpll & DISPLAY_RATE_SELECT_FPA1)) DRM_DEBUG_DRIVER("failed to downclock LVDS!\n"); - - /* ...and lock them again */ - I915_WRITE(PP_CONTROL, I915_READ(PP_CONTROL) & 0x3); } } -- 1.7.7.3 _______________________________________________ Intel-gfx mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/intel-gfx
