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, size_t size,
  50                                          enum dma_data_direction dir,
  51                                          unsigned long attrs);
  52
  53extern void swiotlb_tbl_unmap_single(struct device *hwdev,
  54                                     phys_addr_t tlb_addr,
  55                                     size_t size, enum dma_data_direction dir,
  56                                     unsigned long attrs);
  57
  58extern void swiotlb_tbl_sync_single(struct device *hwdev,
  59                                    phys_addr_t tlb_addr,
  60                                    size_t size, enum dma_data_direction dir,
  61                                    enum dma_sync_target target);
  62
  63#ifdef CONFIG_SWIOTLB
  64extern enum swiotlb_force swiotlb_force;
  65extern phys_addr_t io_tlb_start, io_tlb_end;
  66
  67static inline bool is_swiotlb_buffer(phys_addr_t paddr)
  68{
  69        return paddr >= io_tlb_start && paddr < io_tlb_end;
  70}
  71
  72bool swiotlb_map(struct device *dev, phys_addr_t *phys, dma_addr_t *dma_addr,
  73                size_t size, enum dma_data_direction dir, unsigned long attrs);
  74void __init swiotlb_exit(void);
  75unsigned int swiotlb_max_segment(void);
  76size_t swiotlb_max_mapping_size(struct device *dev);
  77bool is_swiotlb_active(void);
  78#else
  79#define swiotlb_force SWIOTLB_NO_FORCE
  80static inline bool is_swiotlb_buffer(phys_addr_t paddr)
  81{
  82        return false;
  83}
  84static inline bool swiotlb_map(struct device *dev, phys_addr_t *phys,
  85                dma_addr_t *dma_addr, size_t size, enum dma_data_direction dir,
  86                unsigned long attrs)
  87{
  88        return false;
  89}
  90static inline void swiotlb_exit(void)
  91{
  92}
  93static inline unsigned int swiotlb_max_segment(void)
  94{
  95        return 0;
  96}
  97static inline size_t swiotlb_max_mapping_size(struct device *dev)
  98{
  99        return SIZE_MAX;
 100}
 101
 102static inline bool is_swiotlb_active(void)
 103{
 104        return false;
 105}
 106#endif /* CONFIG_SWIOTLB */
 107
 108extern void swiotlb_print_info(void);
 109extern void swiotlb_set_max_segment(unsigned int);
 110
 111#endif /* __LINUX_SWIOTLB_H */
 112