The arch_setup_dma_ops() function is in charge of setting dma_ops with a call to set_dma_ops(). set_dma_ops() is also called from
- highbank and mvebu bus notifiers - dmabounce (to be replaced with swiotlb) - arm_iommu_attach_device (arm_iommu_attach_device is itself called from IOMMU and bus master device drivers) To allow the arch_setup_dma_ops() call to be moved from device add time to device probe time we must ensure that dma_ops already setup by any of the above callers will not be overriden. Aftering replacing dmabounce with swiotlb, converting IOMMU drivers to of_xlate and taking care of highbank and mvebu, the workaround should be removed. Signed-off-by: Laurent Pinchart <[email protected]> --- arch/arm/mm/dma-mapping.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index 09c5fe3d30c2..7aa5e339a596 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -2117,6 +2117,15 @@ void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size, struct dma_map_ops *dma_ops; dev->archdata.dma_coherent = coherent; + + /* + * Don't override the dma_ops if they have already been set. Ideally + * this should be the only location where dma_ops are set, remove this + * check when all other callers of set_dma_ops will have disappeared. + */ + if (dev->archdata.dma_ops) + return; + if (arm_setup_iommu_dma_ops(dev, dma_base, size, iommu)) dma_ops = arm_get_iommu_dma_map_ops(coherent); else -- 2.3.6 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
