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