drm/i915: Use pci_resource functions for BARs.

This was leftover crap from kill-agp. The current code is theoretically
broken for 64b bars. (I resist removing theoretically because I am too
lazy to test).

We still need to ioremap things ourselves because we want to ioremap_wc
the PTEs.

v2: Forgot to kill the tmp variable in v1

CC: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
index 35fec1e..51f79bb 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
@@ -609,7 +609,6 @@
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	phys_addr_t gtt_bus_addr;
 	u16 snb_gmch_ctl;
-	u32 tmp;
 	int ret;
 
 	/* On modern platforms we need not worry ourself with the legacy
@@ -638,12 +637,9 @@
 	if (!pci_set_dma_mask(dev->pdev, DMA_BIT_MASK(40)))
 		pci_set_consistent_dma_mask(dev->pdev, DMA_BIT_MASK(40));
 
-	pci_read_config_dword(dev->pdev, PCI_BASE_ADDRESS_0, &tmp);
 	/* For GEN6+ the PTEs for the ggtt live at 2MB + BAR0 */
-	gtt_bus_addr = (tmp & PCI_BASE_ADDRESS_MEM_MASK) + (2<<20);
-
-	pci_read_config_dword(dev->pdev, PCI_BASE_ADDRESS_2, &tmp);
-	dev_priv->mm.gtt->gma_bus_addr = tmp & PCI_BASE_ADDRESS_MEM_MASK;
+	gtt_bus_addr = pci_resource_start(dev->pdev, 0) + (2<<20);
+	dev_priv->mm.gtt->gma_bus_addr = pci_resource_start(dev->pdev, 2);
 
 	/* i9xx_setup */
 	pci_read_config_word(dev->pdev, SNB_GMCH_CTRL, &snb_gmch_ctl);