i915-vtd.patch

diff -rupN a/drivers/gpu/drm/i915/i915_dma.c c/drivers/gpu/drm/i915/i915_dma.c
--- a/drivers/gpu/drm/i915/i915_dma.c   2014-06-08 20:19:54.000000000 +0200
+++ c/drivers/gpu/drm/i915/i915_dma.c   2014-07-19 18:16:38.091226909 +0200
@@ -1369,6 +1369,12 @@ static int i915_load_modeset_init(struct
     */
    intel_fbdev_initial_config(dev);

+   /*
+    * Must do this after fbcon init so that
+    * vgacon_save_screen() works during the handover.
+    */
+   i915_disable_vga_mem(dev);
+
    /* Only enable hotplug handling once the fbdev is fully set up. */
    dev_priv->enable_hotplug_processing = true;

diff -rupN a/drivers/gpu/drm/i915/intel_display.c c/drivers/gpu/drm/i915/intel_display.c
--- a/drivers/gpu/drm/i915/intel_display.c  2014-06-08 20:19:54.000000000 +0200
+++ c/drivers/gpu/drm/i915/intel_display.c  2014-07-19 18:13:17.821240737 +0200
@@ -11279,6 +11279,33 @@ static void i915_disable_vga(struct drm_
    POSTING_READ(vga_reg);
 }

+static void i915_enable_vga_mem(struct drm_device *dev)
+{
+   /* Enable VGA memory on Intel HD */
+   if (HAS_PCH_SPLIT(dev)) {
+       vga_get_uninterruptible(dev->pdev, VGA_RSRC_LEGACY_IO);
+       outb(inb(VGA_MSR_READ) | VGA_MSR_MEM_EN, VGA_MSR_WRITE);
+       vga_set_legacy_decoding(dev->pdev, VGA_RSRC_LEGACY_IO |
+                          VGA_RSRC_LEGACY_MEM |
+                          VGA_RSRC_NORMAL_IO |
+                          VGA_RSRC_NORMAL_MEM);
+       vga_put(dev->pdev, VGA_RSRC_LEGACY_IO);
+   }
+}
+
+void i915_disable_vga_mem(struct drm_device *dev)
+{
+   /* Disable VGA memory on Intel HD */
+   if (HAS_PCH_SPLIT(dev)) {
+       vga_get_uninterruptible(dev->pdev, VGA_RSRC_LEGACY_IO);
+       outb(inb(VGA_MSR_READ) & ~VGA_MSR_MEM_EN, VGA_MSR_WRITE);
+       vga_set_legacy_decoding(dev->pdev, VGA_RSRC_LEGACY_IO |
+                          VGA_RSRC_NORMAL_IO |
+                          VGA_RSRC_NORMAL_MEM);
+       vga_put(dev->pdev, VGA_RSRC_LEGACY_IO);
+   }
+}
+
 void intel_modeset_init_hw(struct drm_device *dev)
 {
    intel_prepare_ddi(dev);
@@ -11591,6 +11618,7 @@ void i915_redisable_vga_power_on(struct
    if (!(I915_READ(vga_reg) & VGA_DISP_DISABLE)) {
        DRM_DEBUG_KMS("Something enabled VGA plane, disabling it\n");
        i915_disable_vga(dev);
+       i915_disable_vga_mem(dev);
    }
 }

@@ -11845,6 +11873,8 @@ void intel_modeset_cleanup(struct drm_de

    intel_disable_fbc(dev);

+   i915_enable_vga_mem(dev);
+
    intel_disable_gt_powersave(dev);

    ironlake_teardown_rc6(dev);
diff -rupN a/drivers/gpu/drm/i915/intel_drv.h c/drivers/gpu/drm/i915/intel_drv.h
--- a/drivers/gpu/drm/i915/intel_drv.h  2014-06-08 20:19:54.000000000 +0200
+++ c/drivers/gpu/drm/i915/intel_drv.h  2014-07-19 18:13:17.821240737 +0200
@@ -913,7 +913,7 @@ void intel_runtime_pm_put(struct drm_i91
 void intel_init_runtime_pm(struct drm_i915_private *dev_priv);
 void intel_fini_runtime_pm(struct drm_i915_private *dev_priv);
 void ilk_wm_get_hw_state(struct drm_device *dev);
-
+extern void i915_disable_vga_mem(struct drm_device *dev);

 /* intel_sdvo.c */
 bool intel_sdvo_init(struct drm_device *dev, uint32_t sdvo_reg, bool is_sdvob);
diff -rupN a/include/linux/vgaarb.h c/include/linux/vgaarb.h
--- a/include/linux/vgaarb.h    2014-06-08 20:19:54.000000000 +0200
+++ c/include/linux/vgaarb.h    2014-07-19 18:13:50.224566563 +0200
@@ -65,8 +65,15 @@ struct pci_dev;
  *     out of the arbitration process (and can be safe to take
  *     interrupts at any time.
  */
+#if defined(CONFIG_VGA_ARB)
 extern void vga_set_legacy_decoding(struct pci_dev *pdev,
                    unsigned int decodes);
+#else
+static inline void vga_set_legacy_decoding(struct pci_dev *pdev,
+                      unsigned int decodes)
+{
+}
+#endif

 /**
  *     vga_get         - acquire & locks VGA resources