drm/vgaarb: add VGA arbitration support to the drm and kms.

[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / gpu / drm / i915 / intel_display.c

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 155719ff99d148d06ca93a9720e6e15c830e259e..0227b1652906cc0ad345863f2ead6c8bce6025dc 100644 (file)
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -3917,3 +3917,20 @@ struct drm_encoder *intel_best_encoder(struct drm_connector *connector)
 
        return &intel_output->enc;
 }
+
+/*
+ * set vga decode state - true == enable VGA decode
+ */
+int intel_modeset_vga_set_state(struct drm_device *dev, bool state)
+{
+       struct drm_i915_private *dev_priv = dev->dev_private;
+       u16 gmch_ctrl;
+
+       pci_read_config_word(dev_priv->bridge_dev, INTEL_GMCH_CTRL, &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);
+       return 0;
+}