intel-gtt: fix memory corruption with GM965 and >4GB RAM

Commit Message

Chris Wilson Feb. 25, 2011, 8:22 p.m. UTC

None

Patch

diff --git a/drivers/gpu/drm/i915/i915_dma.c
b/drivers/gpu/drm/i915/i915_dma.c
index ffa2196..268e448 100644
--- a/drivers/gpu/drm/i915/i915_dma.c
+++ b/drivers/gpu/drm/i915/i915_dma.c
@@ -1896,6 +1896,8 @@  int i915_driver_load(struct drm_device *dev,
unsigned long
        /* overlay on gen2 is broken and can't address above 1G */
        if (IS_GEN2(dev))
                dma_set_coherent_mask(&dev->pdev->dev, DMA_BIT_MASK(30));
+       if (IS_BRROADWATER(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);

to prevent hitting the erratum.

However your bug looks to be:

diff --git a/drivers/gpu/drm/i915/i915_dma.c
b/drivers/gpu/drm/i915/i915_dma.c
index ffa2196..3b80507 100644
--- a/drivers/gpu/drm/i915/i915_dma.c
+++ b/drivers/gpu/drm/i915/i915_dma.c
@@ -66,9 +66,9 @@  static int i915_init_phys_hws(struct drm_device *dev)
 
        memset_io(ring->status_page.page_addr, 0, PAGE_SIZE);
 
-       if (INTEL_INFO(dev)->gen >= 4)
-               dev_priv->dma_status_page |= (dev_priv->dma_status_page >> 28) &
-                                            0xf0;
+       if (INTEL_INFO(dev)->gen >= 4) /* 36-bit addressing */
+               dev_priv->dma_status_page |=
+                       (dev_priv->status_page_dmah->busaddr >> 28) & 0xf0;
 
        I915_WRITE(HWS_PGA, dev_priv->dma_status_page);
        DRM_DEBUG_DRIVER("Enabled hardware status page\n");