diff options
Diffstat (limited to 'arch/arm/mm/dma-mapping.c')
-rw-r--r-- | arch/arm/mm/dma-mapping.c | 89 |
1 files changed, 64 insertions, 25 deletions
diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index 0a75058c11f3..6774b03aa405 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -1,12 +1,9 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * linux/arch/arm/mm/dma-mapping.c * * Copyright (C) 2000-2004 Russell King * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. - * * DMA uncached mapping support. */ #include <linux/module.h> @@ -18,6 +15,7 @@ #include <linux/init.h> #include <linux/device.h> #include <linux/dma-mapping.h> +#include <linux/dma-noncoherent.h> #include <linux/dma-contiguous.h> #include <linux/highmem.h> #include <linux/memblock.h> @@ -219,25 +217,7 @@ EXPORT_SYMBOL(arm_coherent_dma_ops); static int __dma_supported(struct device *dev, u64 mask, bool warn) { - unsigned long max_dma_pfn; - - /* - * If the mask allows for more memory than we can address, - * and we actually have that much memory, then we must - * indicate that DMA to this device is not supported. - */ - if (sizeof(mask) != sizeof(dma_addr_t) && - mask > (dma_addr_t)~0 && - dma_to_pfn(dev, ~0) < max_pfn - 1) { - if (warn) { - dev_warn(dev, "Coherent DMA mask %#llx is larger than dma_addr_t allows\n", - mask); - dev_warn(dev, "Driver did not use or check the return value from dma_set_coherent_mask()?\n"); - } - return 0; - } - - max_dma_pfn = min(max_pfn, arm_dma_pfn_limit); + unsigned long max_dma_pfn = min(max_pfn, arm_dma_pfn_limit); /* * Translate the device's DMA mask to a PFN limit. This @@ -496,8 +476,7 @@ void __init dma_contiguous_remap(void) } } -static int __dma_update_pte(pte_t *pte, pgtable_t token, unsigned long addr, - void *data) +static int __dma_update_pte(pte_t *pte, unsigned long addr, void *data) { struct page *page = virt_to_page(addr); pgprot_t prot = *(pgprot_t *)data; @@ -1147,6 +1126,19 @@ int arm_dma_supported(struct device *dev, u64 mask) static const struct dma_map_ops *arm_get_dma_map_ops(bool coherent) { + /* + * When CONFIG_ARM_LPAE is set, physical address can extend above + * 32-bits, which then can't be addressed by devices that only support + * 32-bit DMA. + * Use the generic dma-direct / swiotlb ops code in that case, as that + * handles bounce buffering for us. + * + * Note: this checks CONFIG_ARM_LPAE instead of CONFIG_SWIOTLB as the + * latter is also selected by the Xen code, but that code for now relies + * on non-NULL dev_dma_ops. To be cleaned up later. + */ + if (IS_ENABLED(CONFIG_ARM_LPAE)) + return NULL; return coherent ? &arm_coherent_dma_ops : &arm_dma_ops; } @@ -2351,6 +2343,9 @@ void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size, const struct dma_map_ops *dma_ops; dev->archdata.dma_coherent = coherent; +#ifdef CONFIG_SWIOTLB + dev->dma_coherent = coherent; +#endif /* * Don't override the dma_ops if they have already been set. Ideally @@ -2385,3 +2380,47 @@ void arch_teardown_dma_ops(struct device *dev) /* Let arch_setup_dma_ops() start again from scratch upon re-probe */ set_dma_ops(dev, NULL); } + +#ifdef CONFIG_SWIOTLB +void arch_sync_dma_for_device(struct device *dev, phys_addr_t paddr, + size_t size, enum dma_data_direction dir) +{ + __dma_page_cpu_to_dev(phys_to_page(paddr), paddr & (PAGE_SIZE - 1), + size, dir); +} + +void arch_sync_dma_for_cpu(struct device *dev, phys_addr_t paddr, + size_t size, enum dma_data_direction dir) +{ + __dma_page_dev_to_cpu(phys_to_page(paddr), paddr & (PAGE_SIZE - 1), + size, dir); +} + +long arch_dma_coherent_to_pfn(struct device *dev, void *cpu_addr, + dma_addr_t dma_addr) +{ + return dma_to_pfn(dev, dma_addr); +} + +pgprot_t arch_dma_mmap_pgprot(struct device *dev, pgprot_t prot, + unsigned long attrs) +{ + if (!dev_is_dma_coherent(dev)) + return __get_dma_pgprot(attrs, prot); + return prot; +} + +void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle, + gfp_t gfp, unsigned long attrs) +{ + return __dma_alloc(dev, size, dma_handle, gfp, + __get_dma_pgprot(attrs, PAGE_KERNEL), false, + attrs, __builtin_return_address(0)); +} + +void arch_dma_free(struct device *dev, size_t size, void *cpu_addr, + dma_addr_t dma_handle, unsigned long attrs) +{ + __arm_dma_free(dev, size, cpu_addr, dma_handle, attrs, false); +} +#endif /* CONFIG_SWIOTLB */ |