LXR linux/include/linux/swiotlb.h

   1/* SPDX-License-Identifier: GPL-2.0 */
   2#ifndef __LINUX_SWIOTLB_H
   3#define __LINUX_SWIOTLB_H
   4
   5#include <linux/dma-direction.h>
   6#include <linux/init.h>
   7#include <linux/types.h>
   8
   9struct device;
  10struct page;
  11struct scatterlist;
  12
  13enum swiotlb_force {
  14        SWIOTLB_NORMAL,         /* Default - depending on HW DMA mask etc. */
  15        SWIOTLB_FORCE,          /* swiotlb=force */
  16        SWIOTLB_NO_FORCE,       /* swiotlb=noforce */
  17};
  18
  19/*
  20 * Maximum allowable number of contiguous slabs to map,
  21 * must be a power of 2.  What is the appropriate value ?
  22 * The complexity of {map,unmap}_single is linearly dependent on this value.
  23 */
  24#define IO_TLB_SEGSIZE  128
  25
  26/*
  27 * log of the size of each IO TLB slab.  The number of slabs is command line
  28 * controllable.
  29 */
  30#define IO_TLB_SHIFT 11
  31
  32extern void swiotlb_init(int verbose);
  33int swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose);
  34extern unsigned long swiotlb_nr_tbl(void);
  35unsigned long swiotlb_size_or_default(void);
  36extern int swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs);
  37extern void __init swiotlb_update_mem_attributes(void);
  38
  39/*
  40 * Enumeration for sync targets
  41 */
  42enum dma_sync_target {
  43        SYNC_FOR_CPU = 0,
  44        SYNC_FOR_DEVICE = 1,
  45};
  46
  47extern phys_addr_t swiotlb_tbl_map_single(struct device *hwdev,
  48                                          dma_addr_t tbl_dma_addr,
  49                                          phys_addr_t phys,
  50                                          size_t mapping_size,
  51                                          size_t alloc_size,
  52                                          enum dma_data_direction dir,
  53                                          unsigned long attrs);
  54
  55extern void swiotlb_tbl_unmap_single(struct device *hwdev,
  56                                     phys_addr_t tlb_addr,
  57                                     size_t mapping_size,
  58                                     size_t alloc_size,
  59                                     enum dma_data_direction dir,
  60                                     unsigned long attrs);
  61
  62extern void swiotlb_tbl_sync_single(struct device *hwdev,
  63                                    phys_addr_t tlb_addr,
  64                                    size_t size, enum dma_data_direction dir,
  65                                    enum dma_sync_target target);
  66
  67dma_addr_t swiotlb_map(struct device *dev, phys_addr_t phys,
  68                size_t size, enum dma_data_direction dir, unsigned long attrs);
  69
  70#ifdef CONFIG_SWIOTLB
  71extern enum swiotlb_force swiotlb_force;
  72extern phys_addr_t io_tlb_start, io_tlb_end;
  73
  74static inline bool is_swiotlb_buffer(phys_addr_t paddr)
  75{
  76        return paddr >= io_tlb_start && paddr < io_tlb_end;
  77}
  78
  79void __init swiotlb_exit(void);
  80unsigned int swiotlb_max_segment(void);
  81size_t swiotlb_max_mapping_size(struct device *dev);
  82bool is_swiotlb_active(void);
  83#else
  84#define swiotlb_force SWIOTLB_NO_FORCE
  85static inline bool is_swiotlb_buffer(phys_addr_t paddr)
  86{
  87        return false;
  88}
  89static inline void swiotlb_exit(void)
  90{
  91}
  92static inline unsigned int swiotlb_max_segment(void)
  93{
  94        return 0;
  95}
  96static inline size_t swiotlb_max_mapping_size(struct device *dev)
  97{
  98        return SIZE_MAX;
  99}
 100
 101static inline bool is_swiotlb_active(void)
 102{
 103        return false;
 104}
 105#endif /* CONFIG_SWIOTLB */
 106
 107extern void swiotlb_print_info(void);
 108extern void swiotlb_set_max_segment(unsigned int);
 109
 110#endif /* __LINUX_SWIOTLB_H */
 111