---

yaml
---
r: 329488
b: refs/heads/master
c: 934d608
h: refs/heads/master
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: ac6ae347a50bfb4667438272c0d48f4fd41154db
+refs/heads/master: 934d6086ea6b165af9218e8dcc2a9e69e1850743

trunk/drivers/gpu/drm/i915/i915_dma.c

@@ -1461,7 +1461,7 @@ int i915_driver_load(struct drm_device *dev, unsigned long flags)
 {
 	struct drm_i915_private *dev_priv;
 	struct intel_device_info *info;
-	int ret = 0, mmio_bar;
+	int ret = 0, mmio_bar, mmio_size;
 	uint32_t aperture_size;
 
 	info = (struct intel_device_info *) flags;
@@ -1526,7 +1526,19 @@ int i915_driver_load(struct drm_device *dev, unsigned long flags)
 		dma_set_coherent_mask(&dev->pdev->dev, DMA_BIT_MASK(32));
 
 	mmio_bar = IS_GEN2(dev) ? 1 : 0;
-	dev_priv->regs = pci_iomap(dev->pdev, mmio_bar, 0);
+	/* Before gen4, the registers and the GTT are behind different BARs.
+	 * However, from gen4 onwards, the registers and the GTT are shared
+	 * in the same BAR, so we want to restrict this ioremap from
+	 * clobbering the GTT which we want ioremap_wc instead. Fortunately,
+	 * the register BAR remains the same size for all the earlier
+	 * generations up to Ironlake.
+	 */
+	if (info->gen < 5)
+		mmio_size = 512*1024;
+	else
+		mmio_size = 2*1024*1024;
+
+	dev_priv->regs = pci_iomap(dev->pdev, mmio_bar, mmio_size);
 	if (!dev_priv->regs) {
 		DRM_ERROR("failed to map registers\n");
 		ret = -EIO;