arch/x86/include/asm/dma-mapping.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _ASM_X86_DMA_MAPPING_H
   3 #define _ASM_X86_DMA_MAPPING_H
   4
   5 /*
   6  * IOMMU interface. See Documentation/DMA-API-HOWTO.txt and
   7  * Documentation/DMA-API.txt for documentation.
   8  */
   9
  10 #include <linux/kmemcheck.h>
  11 #include <linux/scatterlist.h>
  12 #include <linux/dma-debug.h>
  13 #include <asm/io.h>
  14 #include <asm/swiotlb.h>
  15 #include <linux/dma-contiguous.h>
  16 #include <linux/mem_encrypt.h>
  17
  18 #ifdef CONFIG_ISA
  19 # define ISA_DMA_BIT_MASK DMA_BIT_MASK(24)
  20 #else
  21 # define ISA_DMA_BIT_MASK DMA_BIT_MASK(32)
  22 #endif
  23
  24 extern int iommu_merge;
  25 extern struct device x86_dma_fallback_dev;
  26 extern int panic_on_overflow;
  27
  28 extern const struct dma_map_ops *dma_ops;
  29
  30 static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
  31 {
  32         return dma_ops;
  33 }
  34
  35 bool arch_dma_alloc_attrs(struct device **dev, gfp_t *gfp);
  36 #define arch_dma_alloc_attrs arch_dma_alloc_attrs
  37
  38 extern void *dma_generic_alloc_coherent(struct device *dev, size_t size,
  39                                         dma_addr_t *dma_addr, gfp_t flag,
  40                                         unsigned long attrs);
  41
  42 extern void dma_generic_free_coherent(struct device *dev, size_t size,
  43                                       void *vaddr, dma_addr_t dma_addr,
  44                                       unsigned long attrs);
  45
  46 #ifdef CONFIG_X86_DMA_REMAP /* Platform code defines bridge-specific code */
  47 extern bool dma_capable(struct device *dev, dma_addr_t addr, size_t size);
  48 extern dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr);
  49 extern phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr);
  50 #else
  51
  52 static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
  53 {
  54         if (!dev->dma_mask)
  55                 return 0;
  56
  57         return addr + size - 1 <= *dev->dma_mask;
  58 }
  59
  60 static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
  61 {
  62         return __sme_set(paddr);
  63 }
  64
  65 static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr)
  66 {
  67         return __sme_clr(daddr);
  68 }
  69 #endif /* CONFIG_X86_DMA_REMAP */
  70
  71 static inline unsigned long dma_alloc_coherent_mask(struct device *dev,
  72                                                     gfp_t gfp)
  73 {
  74         unsigned long dma_mask = 0;
  75
  76         dma_mask = dev->coherent_dma_mask;
  77         if (!dma_mask)
  78                 dma_mask = (gfp & GFP_DMA) ? DMA_BIT_MASK(24) : DMA_BIT_MASK(32);
  79
  80         return dma_mask;
  81 }
  82
  83 static inline gfp_t dma_alloc_coherent_gfp_flags(struct device *dev, gfp_t gfp)
  84 {
  85         unsigned long dma_mask = dma_alloc_coherent_mask(dev, gfp);
  86
  87         if (dma_mask <= DMA_BIT_MASK(24))
  88                 gfp |= GFP_DMA;
  89 #ifdef CONFIG_X86_64
  90         if (dma_mask <= DMA_BIT_MASK(32) && !(gfp & GFP_DMA))
  91                 gfp |= GFP_DMA32;
  92 #endif
  93        return gfp;
  94 }
  95
  96 #endif