diff options
Diffstat (limited to 'drivers/iommu')
| -rw-r--r-- | drivers/iommu/dma-iommu.c | 27 |
1 files changed, 27 insertions, 0 deletions
diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c index 83eb99bfb990..5f49ed653f98 100644 --- a/drivers/iommu/dma-iommu.c +++ b/drivers/iommu/dma-iommu.c @@ -878,6 +878,33 @@ static int __finalise_sg(struct device *dev, struct scatterlist *sg, int nents, unsigned int cur_len = 0, max_len = dma_get_max_seg_size(dev); int i, count = 0; + /* + * The Intel graphic driver is used to assume that the returned + * sg list is not combound. This blocks the efforts of converting + * Intel IOMMU driver to dma-iommu api's. Add this quirk to make the + * device driver work and should be removed once it's fixed in i915 + * driver. + */ + if (IS_ENABLED(CONFIG_DRM_I915) && dev_is_pci(dev) && + to_pci_dev(dev)->vendor == PCI_VENDOR_ID_INTEL && + (to_pci_dev(dev)->class >> 16) == PCI_BASE_CLASS_DISPLAY) { + for_each_sg(sg, s, nents, i) { + unsigned int s_iova_off = sg_dma_address(s); + unsigned int s_length = sg_dma_len(s); + unsigned int s_iova_len = s->length; + + s->offset += s_iova_off; + s->length = s_length; + sg_dma_address(s) = dma_addr + s_iova_off; + sg_dma_len(s) = s_length; + dma_addr += s_iova_len; + + pr_info_once("sg combining disabled due to i915 driver\n"); + } + + return nents; + } + for_each_sg(sg, s, nents, i) { /* Restore this segment's original unaligned fields first */ unsigned int s_iova_off = sg_dma_address(s); |