agp/intel-agp: Set dma_mask for capable chipsets before agp_add_bridge()

We should set this before calling agp_add_bridge() so that it's done
before we map the scratch page too.

This should probably fix the regression reported as k.o. bug #14627.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/char/agp/intel-agp.c

@@ -1161,12 +1161,6 @@ static int intel_i915_configure(void)
 
 	intel_i9xx_setup_flush();
 
-#ifdef USE_PCI_DMA_API 
-	if (pci_set_dma_mask(intel_private.pcidev, DMA_BIT_MASK(36)))
-		dev_err(&intel_private.pcidev->dev,
-			"set gfx device dma mask 36bit failed!\n");
-#endif
-
 	return 0;
 }
 
@@ -2456,6 +2450,11 @@ static int __devinit agp_intel_probe(struct pci_dev *pdev,
 				&bridge->mode);
 	}
 
+	if (bridge->driver->mask_memory == intel_i965_mask_memory)
+		if (pci_set_dma_mask(intel_private.pcidev, DMA_BIT_MASK(36)))
+			dev_err(&intel_private.pcidev->dev,
+				"set gfx device dma mask 36bit failed!\n");
+
 	pci_set_drvdata(pdev, bridge);
 	return agp_add_bridge(bridge);
 }