diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2020-12-22 13:19:43 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-12-22 13:19:43 -0800 |
commit | 347d81b68b8f7044c9ce3fefa130a736ca916176 (patch) | |
tree | ee07d2f350f34ae0a8bdd904251faa61144cb778 /arch/powerpc/kernel | |
parent | 4f06f210673e6841439a0f91fcde64960cdbeb5c (diff) | |
parent | 7679325702c90aecd393cd7cde685576c14489c0 (diff) |
Merge tag 'dma-mapping-5.11' of git://git.infradead.org/users/hch/dma-mapping
Pull dma-mapping updates from Christoph Hellwig:
- support for a partial IOMMU bypass (Alexey Kardashevskiy)
- add a DMA API benchmark (Barry Song)
- misc fixes (Tiezhu Yang, tangjianqiang)
* tag 'dma-mapping-5.11' of git://git.infradead.org/users/hch/dma-mapping:
selftests/dma: add test application for DMA_MAP_BENCHMARK
dma-mapping: add benchmark support for streaming DMA APIs
dma-contiguous: fix a typo error in a comment
dma-pool: no need to check return value of debugfs_create functions
powerpc/dma: Fallback to dma_ops when persistent memory present
dma-mapping: Allow mixing bypass and mapped DMA operation
Diffstat (limited to 'arch/powerpc/kernel')
-rw-r--r-- | arch/powerpc/kernel/dma-iommu.c | 71 |
1 files changed, 69 insertions, 2 deletions
diff --git a/arch/powerpc/kernel/dma-iommu.c b/arch/powerpc/kernel/dma-iommu.c index a1c744194018..111249fd619d 100644 --- a/arch/powerpc/kernel/dma-iommu.c +++ b/arch/powerpc/kernel/dma-iommu.c @@ -10,6 +10,63 @@ #include <linux/pci.h> #include <asm/iommu.h> +#ifdef CONFIG_ARCH_HAS_DMA_MAP_DIRECT +#define can_map_direct(dev, addr) \ + ((dev)->bus_dma_limit >= phys_to_dma((dev), (addr))) + +bool arch_dma_map_page_direct(struct device *dev, phys_addr_t addr) +{ + if (likely(!dev->bus_dma_limit)) + return false; + + return can_map_direct(dev, addr); +} + +#define is_direct_handle(dev, h) ((h) >= (dev)->archdata.dma_offset) + +bool arch_dma_unmap_page_direct(struct device *dev, dma_addr_t dma_handle) +{ + if (likely(!dev->bus_dma_limit)) + return false; + + return is_direct_handle(dev, dma_handle); +} + +bool arch_dma_map_sg_direct(struct device *dev, struct scatterlist *sg, + int nents) +{ + struct scatterlist *s; + int i; + + if (likely(!dev->bus_dma_limit)) + return false; + + for_each_sg(sg, s, nents, i) { + if (!can_map_direct(dev, sg_phys(s) + s->offset + s->length)) + return false; + } + + return true; +} + +bool arch_dma_unmap_sg_direct(struct device *dev, struct scatterlist *sg, + int nents) +{ + struct scatterlist *s; + int i; + + if (likely(!dev->bus_dma_limit)) + return false; + + for_each_sg(sg, s, nents, i) { + if (!is_direct_handle(dev, s->dma_address + s->length)) + return false; + } + + return true; +} +#endif /* CONFIG_ARCH_HAS_DMA_MAP_DIRECT */ + /* * Generic iommu implementation */ @@ -90,8 +147,18 @@ int dma_iommu_dma_supported(struct device *dev, u64 mask) struct iommu_table *tbl = get_iommu_table_base(dev); if (dev_is_pci(dev) && dma_iommu_bypass_supported(dev, mask)) { - dev->dma_ops_bypass = true; - dev_dbg(dev, "iommu: 64-bit OK, using fixed ops\n"); + /* + * dma_iommu_bypass_supported() sets dma_max when there is + * 1:1 mapping but it is somehow limited. + * ibm,pmemory is one example. + */ + dev->dma_ops_bypass = dev->bus_dma_limit == 0; + if (!dev->dma_ops_bypass) + dev_warn(dev, + "iommu: 64-bit OK but direct DMA is limited by %llx\n", + dev->bus_dma_limit); + else + dev_dbg(dev, "iommu: 64-bit OK, using fixed ops\n"); return 1; } |