From a885b3ccc74d8e38074e1c43a47c354c5ea0b01e Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Tue, 17 Dec 2013 14:34:50 +0000 Subject: [PATCH] drm/i915: Use the correct GMCH_CTRL register for Sandybridge+ MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The GMCH_CTRL register (or MGCC in the spec) is at a different address on Sandybridge, and the address to which we currently write to is undefined. These stray writes appear to upset (hard hang) my Ivybridge machine whilst it is in UEFI mode. Note that the register is still marked as locked RO on Sandybridge, so vgaarb is still dysfunctional. Signed-off-by: Chris Wilson Cc: Jani Nikula Cc: Ville Syrjälä Cc: stable@vger.kernel.org Reviewed-by: Jani Nikula Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/intel_display.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index 4049a65a9f8c..54e82a80cf50 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -11126,14 +11126,15 @@ void intel_connector_attach_encoder(struct intel_connector *connector, int intel_modeset_vga_set_state(struct drm_device *dev, bool state) { struct drm_i915_private *dev_priv = dev->dev_private; + unsigned reg = INTEL_INFO(dev)->gen >= 6 ? SNB_GMCH_CTRL : INTEL_GMCH_CTRL; u16 gmch_ctrl; - pci_read_config_word(dev_priv->bridge_dev, INTEL_GMCH_CTRL, &gmch_ctrl); + pci_read_config_word(dev_priv->bridge_dev, reg, &gmch_ctrl); if (state) gmch_ctrl &= ~INTEL_GMCH_VGA_DISABLE; else gmch_ctrl |= INTEL_GMCH_VGA_DISABLE; - pci_write_config_word(dev_priv->bridge_dev, INTEL_GMCH_CTRL, gmch_ctrl); + pci_write_config_word(dev_priv->bridge_dev, reg, gmch_ctrl); return 0; }