On Broxton per specification the GTT has to be mapped as uncached. This was caught by the PTE write readback warning, which showed a corrupted PTE value with using the current write-combine mapping. Signed-off-by: Imre Deak <imre.deak@xxxxxxxxx> --- drivers/gpu/drm/i915/i915_gem_gtt.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c index 4311292..8edf3cf 100644 --- a/drivers/gpu/drm/i915/i915_gem_gtt.c +++ b/drivers/gpu/drm/i915/i915_gem_gtt.c @@ -2065,7 +2065,10 @@ static int ggtt_probe_common(struct drm_device *dev, gtt_phys_addr = pci_resource_start(dev->pdev, 0) + (pci_resource_len(dev->pdev, 0) / 2); - dev_priv->gtt.gsm = ioremap_wc(gtt_phys_addr, gtt_size); + if (IS_BROXTON(dev)) + dev_priv->gtt.gsm = ioremap_nocache(gtt_phys_addr, gtt_size); + else + dev_priv->gtt.gsm = ioremap_wc(gtt_phys_addr, gtt_size); if (!dev_priv->gtt.gsm) { DRM_ERROR("Failed to map the gtt page table\n"); return -ENOMEM; -- 2.1.0 _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx