diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/gpu/drm/i915/intel_display.c | 51 |
1 files changed, 51 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index 9d3af3cb5a0b..e5badadbdcd2 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -5238,6 +5238,55 @@ static const struct drm_crtc_funcs intel_crtc_funcs = { .page_flip = intel_crtc_page_flip, }; +static void intel_sanitize_modesetting(struct drm_device *dev, + int pipe, int plane) +{ + struct drm_i915_private *dev_priv = dev->dev_private; + u32 reg, val; + + if (HAS_PCH_SPLIT(dev)) + return; + + /* Who knows what state these registers were left in by the BIOS or + * grub? + * + * If we leave the registers in a conflicting state (e.g. with the + * display plane reading from the other pipe than the one we intend + * to use) then when we attempt to teardown the active mode, we will + * not disable the pipes and planes in the correct order -- leaving + * a plane reading from a disabled pipe and possibly leading to + * undefined behaviour. + */ + + reg = DSPCNTR(plane); + val = I915_READ(reg); + + if ((val & DISPLAY_PLANE_ENABLE) == 0) + return; + if (!!(val & DISPPLANE_SEL_PIPE_MASK) == pipe) + return; + + /* This display plane is active and attached to the other CPU pipe. */ + pipe = !pipe; + + /* Disable the plane and wait for it to stop reading from the pipe. */ + I915_WRITE(reg, val & ~DISPLAY_PLANE_ENABLE); + intel_flush_display_plane(dev, plane); + + if (IS_GEN2(dev)) + intel_wait_for_vblank(dev, pipe); + + if (pipe == 0 && (dev_priv->quirks & QUIRK_PIPEA_FORCE)) + return; + + /* Switch off the pipe. */ + reg = PIPECONF(pipe); + val = I915_READ(reg); + if (val & PIPECONF_ENABLE) { + I915_WRITE(reg, val & ~PIPECONF_ENABLE); + intel_wait_for_pipe_off(dev, pipe); + } +} static void intel_crtc_init(struct drm_device *dev, int pipe) { @@ -5289,6 +5338,8 @@ static void intel_crtc_init(struct drm_device *dev, int pipe) setup_timer(&intel_crtc->idle_timer, intel_crtc_idle_timer, (unsigned long)intel_crtc); + + intel_sanitize_modesetting(dev, intel_crtc->pipe, intel_crtc->plane); } int intel_get_pipe_from_crtc_id(struct drm_device *dev, void *data, |