root/include/linux/dma-noncoherent.h

INCLUDED FROM

DEFINITIONS

1. dev_is_dma_coherent
2. dev_is_dma_coherent
3. dma_alloc_need_uncached
4. dma_pgprot
5. arch_dma_cache_sync
6. arch_sync_dma_for_device
7. arch_sync_dma_for_cpu
8. arch_sync_dma_for_cpu_all
9. arch_dma_prep_coherent

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _LINUX_DMA_NONCOHERENT_H
   3 #define _LINUX_DMA_NONCOHERENT_H 1
   4 
   5 #include <linux/dma-mapping.h>
   6 #include <asm/pgtable.h>
   7 
   8 #ifdef CONFIG_ARCH_HAS_DMA_COHERENCE_H
   9 #include <asm/dma-coherence.h>
  10 #elif defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \
  11         defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU) || \
  12         defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL)
  13 static inline bool dev_is_dma_coherent(struct device *dev)
  14 {
  15         return dev->dma_coherent;
  16 }
  17 #else
  18 static inline bool dev_is_dma_coherent(struct device *dev)
  19 {
  20         return true;
  21 }
  22 #endif /* CONFIG_ARCH_HAS_DMA_COHERENCE_H */
  23 
  24 /*
  25  * Check if an allocation needs to be marked uncached to be coherent.
  26  */
  27 static __always_inline bool dma_alloc_need_uncached(struct device *dev,
  28                 unsigned long attrs)
  29 {
  30         if (dev_is_dma_coherent(dev))
  31                 return false;
  32         if (attrs & DMA_ATTR_NO_KERNEL_MAPPING)
  33                 return false;
  34         if (IS_ENABLED(CONFIG_DMA_NONCOHERENT_CACHE_SYNC) &&
  35             (attrs & DMA_ATTR_NON_CONSISTENT))
  36                 return false;
  37         return true;
  38 }
  39 
  40 void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
  41                 gfp_t gfp, unsigned long attrs);
  42 void arch_dma_free(struct device *dev, size_t size, void *cpu_addr,
  43                 dma_addr_t dma_addr, unsigned long attrs);
  44 long arch_dma_coherent_to_pfn(struct device *dev, void *cpu_addr,
  45                 dma_addr_t dma_addr);
  46 
  47 #ifdef CONFIG_MMU
  48 /*
  49  * Page protection so that devices that can't snoop CPU caches can use the
  50  * memory coherently.  We default to pgprot_noncached which is usually used
  51  * for ioremap as a safe bet, but architectures can override this with less
  52  * strict semantics if possible.
  53  */
  54 #ifndef pgprot_dmacoherent
  55 #define pgprot_dmacoherent(prot)        pgprot_noncached(prot)
  56 #endif
  57 
  58 pgprot_t dma_pgprot(struct device *dev, pgprot_t prot, unsigned long attrs);
  59 #else
  60 static inline pgprot_t dma_pgprot(struct device *dev, pgprot_t prot,
  61                 unsigned long attrs)
  62 {
  63         return prot;    /* no protection bits supported without page tables */
  64 }
  65 #endif /* CONFIG_MMU */
  66 
  67 #ifdef CONFIG_DMA_NONCOHERENT_CACHE_SYNC
  68 void arch_dma_cache_sync(struct device *dev, void *vaddr, size_t size,
  69                 enum dma_data_direction direction);
  70 #else
  71 static inline void arch_dma_cache_sync(struct device *dev, void *vaddr,
  72                 size_t size, enum dma_data_direction direction)
  73 {
  74 }
  75 #endif /* CONFIG_DMA_NONCOHERENT_CACHE_SYNC */
  76 
  77 #ifdef CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE
  78 void arch_sync_dma_for_device(struct device *dev, phys_addr_t paddr,
  79                 size_t size, enum dma_data_direction dir);
  80 #else
  81 static inline void arch_sync_dma_for_device(struct device *dev,
  82                 phys_addr_t paddr, size_t size, enum dma_data_direction dir)
  83 {
  84 }
  85 #endif /* ARCH_HAS_SYNC_DMA_FOR_DEVICE */
  86 
  87 #ifdef CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU
  88 void arch_sync_dma_for_cpu(struct device *dev, phys_addr_t paddr,
  89                 size_t size, enum dma_data_direction dir);
  90 #else
  91 static inline void arch_sync_dma_for_cpu(struct device *dev,
  92                 phys_addr_t paddr, size_t size, enum dma_data_direction dir)
  93 {
  94 }
  95 #endif /* ARCH_HAS_SYNC_DMA_FOR_CPU */
  96 
  97 #ifdef CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL
  98 void arch_sync_dma_for_cpu_all(struct device *dev);
  99 #else
 100 static inline void arch_sync_dma_for_cpu_all(struct device *dev)
 101 {
 102 }
 103 #endif /* CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL */
 104 
 105 #ifdef CONFIG_ARCH_HAS_DMA_PREP_COHERENT
 106 void arch_dma_prep_coherent(struct page *page, size_t size);
 107 #else
 108 static inline void arch_dma_prep_coherent(struct page *page, size_t size)
 109 {
 110 }
 111 #endif /* CONFIG_ARCH_HAS_DMA_PREP_COHERENT */
 112 
 113 void *uncached_kernel_address(void *addr);
 114 void *cached_kernel_address(void *addr);
 115 
 116 #endif /* _LINUX_DMA_NONCOHERENT_H */