3 files changed, 38 insertions, 3 deletions

diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c
index fdaa0915ce56..3de60503378e 100644
--- a/drivers/gpu/drm/i915/i915_dma.c
+++ b/drivers/gpu/drm/i915/i915_dma.c
@@ -1290,9 +1290,12 @@ static int i915_load_modeset_init(struct drm_device *dev)
          * then we do not take part in VGA arbitration and the
          * vga_client_register() fails with -ENODEV.
          */
-        ret = vga_client_register(dev->pdev, dev, NULL, i915_vga_set_decode);
-        if (ret && ret != -ENODEV)
-                goto out;
+        if (!HAS_PCH_SPLIT(dev)) {
+                ret = vga_client_register(dev->pdev, dev, NULL,
+                                          i915_vga_set_decode);
+                if (ret && ret != -ENODEV)
+                        goto out;
+        }
 
         intel_register_dsm_handler();
 
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index a1e502b07266..73dec62f871f 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -10041,6 +10041,15 @@ static void i915_disable_vga(struct drm_device *dev)
         outb(SR01, VGA_SR_INDEX);
         sr1 = inb(VGA_SR_DATA);
         outb(sr1 | 1<<5, VGA_SR_DATA);
+
+        /* Disable VGA memory on Intel HD */
+        if (HAS_PCH_SPLIT(dev)) {
+                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);
         udelay(300);
 
@@ -10048,6 +10057,20 @@ static void i915_disable_vga(struct drm_device *dev)
         POSTING_READ(vga_reg);
 }
 
+static void i915_enable_vga(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 intel_modeset_init_hw(struct drm_device *dev)
 {
         intel_init_power_well(dev);
@@ -10539,6 +10562,8 @@ void intel_modeset_cleanup(struct drm_device *dev)
 
         intel_disable_fbc(dev);
 
+        i915_enable_vga(dev);
+
         intel_disable_gt_powersave(dev);
 
         ironlake_teardown_rc6(dev);
diff --git a/include/linux/vgaarb.h b/include/linux/vgaarb.h
index 2c02f3a8d2ba..80cf8173a65b 100644
--- a/include/linux/vgaarb.h
+++ b/include/linux/vgaarb.h
@@ -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