From d3899a1634c427dbc7c43a6133b126a58c66a934 Mon Sep 17 00:00:00 2001 From: Daniel Vetter Date: Mon, 30 Aug 2010 21:25:23 +0200 Subject: drm/i915: overlay on gen2 can't address above 1G commit 9f82d23846146990d475f6753be733e55788d88d upstream. So set the coherent dma mask accordingly. This dma mask is only used for physical objects, so it won't really matter allocation-wise. Now this never really surfaced because sane 32bit kernels only have 1G of lowmem. But some eager testers (distros?) still carry around the patch to adjust lowmem via a kconfig option. And the kernel seems to favour high allocations on boot-up, hence the overlay blowing up reliably. Because the patch is tiny and nicely shows how broken gen2 is it's imho worth to merge despite the fact that mucking around with the lowmem/ highmem division is (no longer) supported. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=28318 Signed-off-by: Daniel Vetter Signed-off-by: Chris Wilson Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/i915/i915_dma.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c index 5786737ef04..ce8ff0e5515 100644 --- a/drivers/gpu/drm/i915/i915_dma.c +++ b/drivers/gpu/drm/i915/i915_dma.c @@ -2079,6 +2079,10 @@ int i915_driver_load(struct drm_device *dev, unsigned long flags) goto free_priv; } + /* 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)); + dev_priv->regs = ioremap(base, size); if (!dev_priv->regs) { DRM_ERROR("failed to map registers\n"); -- cgit v1.2.3