49 lines
1.7 KiB
Diff
49 lines
1.7 KiB
Diff
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From: Thierry Reding <treding at nvidia.com>
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The OMAP IOMMU driver unconditionally executes code and registers a
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struct iommu_ops with the platform bus irrespective of whether it runs
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on an OMAP SoC or not. This causes problems in multi-platform kernels
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where drivers for other SoCs will no longer be able to register their
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own struct iommu_ops or even try to use a struct iommu_ops for an IOMMU
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that obviously isn't there.
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The smallest fix I could think of is to check for the existence of any
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OMAP IOMMU devices in the device tree and skip initialization otherwise.
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This fixes a problem on Tegra20 where the DRM driver will try to use the
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obviously non-existent OMAP IOMMU.
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Reported-by: Nicolas Chauvet <kwizart at gmail.com>
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Cc: Tony Lindgren <tony at atomide.com>
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Cc: Suman Anna <s-anna at ti.com>
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Cc: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
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Signed-off-by: Thierry Reding <treding at nvidia.com>
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---
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Changes in v2:
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- do not fix up module exit function since it's dead code
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- drop reference to struct device_node
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drivers/iommu/omap-iommu.c | 7 +++++++
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1 file changed, 7 insertions(+)
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diff --git a/drivers/iommu/omap-iommu.c b/drivers/iommu/omap-iommu.c
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index f59f857b702e..a4ba851825c2 100644
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--- a/drivers/iommu/omap-iommu.c
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+++ b/drivers/iommu/omap-iommu.c
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@@ -1376,6 +1376,13 @@ static int __init omap_iommu_init(void)
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struct kmem_cache *p;
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const unsigned long flags = SLAB_HWCACHE_ALIGN;
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size_t align = 1 << 10; /* L2 pagetable alignement */
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+ struct device_node *np;
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+
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+ np = of_find_matching_node(NULL, omap_iommu_of_match);
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+ if (!np)
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+ return 0;
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+
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+ of_node_put(np);
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p = kmem_cache_create("iopte_cache", IOPTE_TABLE_SIZE, align, flags,
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iopte_cachep_ctor);
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--
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2.1.3
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