--- zzzz-none-000/linux-3.10.107/arch/powerpc/kernel/dma.c 2017-06-27 09:49:32.000000000 +0000 +++ scorpion-7490-727/linux-3.10.107/arch/powerpc/kernel/dma.c 2021-02-04 17:41:59.000000000 +0000 @@ -15,6 +15,8 @@ #include #include #include +#include +#include /* * Generic direct DMA implementation @@ -25,10 +27,44 @@ * default the offset is PCI_DRAM_OFFSET. */ +static u64 __maybe_unused get_pfn_limit(struct device *dev) +{ + u64 pfn = (dev->coherent_dma_mask >> PAGE_SHIFT) + 1; + struct dev_archdata __maybe_unused *sd = &dev->archdata; -void *dma_direct_alloc_coherent(struct device *dev, size_t size, - dma_addr_t *dma_handle, gfp_t flag, - struct dma_attrs *attrs) +#ifdef CONFIG_SWIOTLB + if (sd->max_direct_dma_addr && sd->dma_ops == &swiotlb_dma_ops) + pfn = min_t(u64, pfn, sd->max_direct_dma_addr >> PAGE_SHIFT); +#endif + + return pfn; +} + +static int dma_direct_dma_supported(struct device *dev, u64 mask) +{ +#ifdef CONFIG_PPC64 + u64 limit = get_dma_offset(dev) + (memblock_end_of_DRAM() - 1); + + /* Limit fits in the mask, we are good */ + if (mask >= limit) + return 1; + +#ifdef CONFIG_FSL_SOC + /* Freescale gets another chance via ZONE_DMA/ZONE_DMA32, however + * that will have to be refined if/when they support iommus + */ + return 1; +#endif + /* Sorry ... */ + return 0; +#else + return 1; +#endif +} + +void *__dma_direct_alloc_coherent(struct device *dev, size_t size, + dma_addr_t *dma_handle, gfp_t flag, + struct dma_attrs *attrs) { void *ret; #ifdef CONFIG_NOT_COHERENT_CACHE @@ -40,6 +76,34 @@ #else struct page *page; int node = dev_to_node(dev); +#ifdef CONFIG_FSL_SOC + u64 pfn = get_pfn_limit(dev); + int zone; + + /* + * This code should be OK on other platforms, but we have drivers that + * don't set coherent_dma_mask. As a workaround we just ifdef it. This + * whole routine needs some serious cleanup. + */ + + zone = dma_pfn_limit_to_zone(pfn); + if (zone < 0) { + dev_err(dev, "%s: No suitable zone for pfn %#llx\n", + __func__, pfn); + return NULL; + } + + switch (zone) { + case ZONE_DMA: + flag |= GFP_DMA; + break; +#ifdef CONFIG_ZONE_DMA32 + case ZONE_DMA32: + flag |= GFP_DMA32; + break; +#endif + }; +#endif /* CONFIG_FSL_SOC */ /* ignore region specifiers */ flag &= ~(__GFP_HIGHMEM); @@ -55,9 +119,9 @@ #endif } -void dma_direct_free_coherent(struct device *dev, size_t size, - void *vaddr, dma_addr_t dma_handle, - struct dma_attrs *attrs) +void __dma_direct_free_coherent(struct device *dev, size_t size, + void *vaddr, dma_addr_t dma_handle, + struct dma_attrs *attrs) { #ifdef CONFIG_NOT_COHERENT_CACHE __dma_free_coherent(size, vaddr); @@ -66,6 +130,51 @@ #endif } +static void *dma_direct_alloc_coherent(struct device *dev, size_t size, + dma_addr_t *dma_handle, gfp_t flag, + struct dma_attrs *attrs) +{ + struct iommu_table *iommu; + + /* The coherent mask may be smaller than the real mask, check if + * we can really use the direct ops + */ + if (dma_direct_dma_supported(dev, dev->coherent_dma_mask)) + return __dma_direct_alloc_coherent(dev, size, dma_handle, + flag, attrs); + + /* Ok we can't ... do we have an iommu ? If not, fail */ + iommu = get_iommu_table_base(dev); + if (!iommu) + return NULL; + + /* Try to use the iommu */ + return iommu_alloc_coherent(dev, iommu, size, dma_handle, + dev->coherent_dma_mask, flag, + dev_to_node(dev)); +} + +static void dma_direct_free_coherent(struct device *dev, size_t size, + void *vaddr, dma_addr_t dma_handle, + struct dma_attrs *attrs) +{ + struct iommu_table *iommu; + + /* See comments in dma_direct_alloc_coherent() */ + if (dma_direct_dma_supported(dev, dev->coherent_dma_mask)) + return __dma_direct_free_coherent(dev, size, vaddr, dma_handle, + attrs); + /* Maybe we used an iommu ... */ + iommu = get_iommu_table_base(dev); + + /* If we hit that we should have never allocated in the first + * place so how come we are freeing ? + */ + if (WARN_ON(!iommu)) + return; + iommu_free_coherent(iommu, size, vaddr, dma_handle); +} + int dma_direct_mmap_coherent(struct device *dev, struct vm_area_struct *vma, void *cpu_addr, dma_addr_t handle, size_t size, struct dma_attrs *attrs) @@ -106,18 +215,6 @@ { } -static int dma_direct_dma_supported(struct device *dev, u64 mask) -{ -#ifdef CONFIG_PPC64 - /* Could be improved so platforms can set the limit in case - * they have limited DMA windows - */ - return mask >= get_dma_offset(dev) + (memblock_end_of_DRAM() - 1); -#else - return 1; -#endif -} - static u64 dma_direct_get_required_mask(struct device *dev) { u64 end, mask; @@ -189,14 +286,31 @@ }; EXPORT_SYMBOL(dma_direct_ops); +int dma_set_coherent_mask(struct device *dev, u64 mask) +{ + if (!dma_supported(dev, mask)) { + /* + * We need to special case the direct DMA ops which can + * support a fallback for coherent allocations. There + * is no dma_op->set_coherent_mask() so we have to do + * things the hard way: + */ + if (get_dma_ops(dev) != &dma_direct_ops || + get_iommu_table_base(dev) == NULL || + !dma_iommu_dma_supported(dev, mask)) + return -EIO; + } + dev->coherent_dma_mask = mask; + return 0; +} +EXPORT_SYMBOL(dma_set_coherent_mask); + #define PREALLOC_DMA_DEBUG_ENTRIES (1 << 16) -int dma_set_mask(struct device *dev, u64 dma_mask) +int __dma_set_mask(struct device *dev, u64 dma_mask) { struct dma_map_ops *dma_ops = get_dma_ops(dev); - if (ppc_md.dma_set_mask) - return ppc_md.dma_set_mask(dev, dma_mask); if ((dma_ops != NULL) && (dma_ops->set_dma_mask != NULL)) return dma_ops->set_dma_mask(dev, dma_mask); if (!dev->dma_mask || !dma_supported(dev, dma_mask)) @@ -204,15 +318,27 @@ *dev->dma_mask = dma_mask; return 0; } + +int dma_set_mask(struct device *dev, u64 dma_mask) +{ + if (ppc_md.dma_set_mask) + return ppc_md.dma_set_mask(dev, dma_mask); + + if (dev_is_pci(dev)) { + struct pci_dev *pdev = to_pci_dev(dev); + struct pci_controller *phb = pci_bus_to_host(pdev->bus); + if (phb->controller_ops.dma_set_mask) + return phb->controller_ops.dma_set_mask(pdev, dma_mask); + } + + return __dma_set_mask(dev, dma_mask); +} EXPORT_SYMBOL(dma_set_mask); -u64 dma_get_required_mask(struct device *dev) +u64 __dma_get_required_mask(struct device *dev) { struct dma_map_ops *dma_ops = get_dma_ops(dev); - if (ppc_md.dma_get_required_mask) - return ppc_md.dma_get_required_mask(dev); - if (unlikely(dma_ops == NULL)) return 0; @@ -221,6 +347,21 @@ return DMA_BIT_MASK(8 * sizeof(dma_addr_t)); } + +u64 dma_get_required_mask(struct device *dev) +{ + if (ppc_md.dma_get_required_mask) + return ppc_md.dma_get_required_mask(dev); + + if (dev_is_pci(dev)) { + struct pci_dev *pdev = to_pci_dev(dev); + struct pci_controller *phb = pci_bus_to_host(pdev->bus); + if (phb->controller_ops.dma_get_required_mask) + return phb->controller_ops.dma_get_required_mask(pdev); + } + + return __dma_get_required_mask(dev); +} EXPORT_SYMBOL_GPL(dma_get_required_mask); static int __init dma_init(void)