Merge git://git.infradead.org/users/dwmw2/mtd-2.6.38

[mv-sheeva.git] / drivers / gpu / drm / i915 / i915_dma.c

diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c
index 17bd766f20811ae5622a4276adf78de9a77c5208..e33d9be7df3b7455c4f4f72085079c0450d50903 100644 (file)
--- a/drivers/gpu/drm/i915/i915_dma.c
+++ b/drivers/gpu/drm/i915/i915_dma.c
@@ -1895,6 +1895,17 @@ int i915_driver_load(struct drm_device *dev, unsigned long flags)
        if (IS_GEN2(dev))
                dma_set_coherent_mask(&dev->pdev->dev, DMA_BIT_MASK(30));
 
+       /* 965GM sometimes incorrectly writes to hardware status page (HWS)
+        * using 32bit addressing, overwriting memory if HWS is located
+        * above 4GB.
+        *
+        * The documentation also mentions an issue with undefined
+        * behaviour if any general state is accessed within a page above 4GB,
+        * which also needs to be handled carefully.
+        */
+       if (IS_BROADWATER(dev) || IS_CRESTLINE(dev))
+               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);
        if (!dev_priv->regs) {