Linux kernel mirror (for testing)
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linux
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
67#ifdef CONFIG_SWIOTLB
68extern enum swiotlb_force swiotlb_force;
69extern phys_addr_t io_tlb_start, io_tlb_end;
70
71static inline bool is_swiotlb_buffer(phys_addr_t paddr)
72{
73 return paddr >= io_tlb_start && paddr < io_tlb_end;
74}
75
76bool swiotlb_map(struct device *dev, phys_addr_t *phys, dma_addr_t *dma_addr,
77 size_t size, enum dma_data_direction dir, unsigned long attrs);
78void __init swiotlb_exit(void);
79unsigned int swiotlb_max_segment(void);
80size_t swiotlb_max_mapping_size(struct device *dev);
81bool is_swiotlb_active(void);
82#else
83#define swiotlb_force SWIOTLB_NO_FORCE
84static inline bool is_swiotlb_buffer(phys_addr_t paddr)
85{
86 return false;
87}
88static inline bool swiotlb_map(struct device *dev, phys_addr_t *phys,
89 dma_addr_t *dma_addr, size_t size, enum dma_data_direction dir,
90 unsigned long attrs)
91{
92 return false;
93}
94static inline void swiotlb_exit(void)
95{
96}
97static inline unsigned int swiotlb_max_segment(void)
98{
99 return 0;
100}
101static inline size_t swiotlb_max_mapping_size(struct device *dev)
102{
103 return SIZE_MAX;
104}
105
106static inline bool is_swiotlb_active(void)
107{
108 return false;
109}
110#endif /* CONFIG_SWIOTLB */
111
112extern void swiotlb_print_info(void);
113extern void swiotlb_set_max_segment(unsigned int);
114
115#endif /* __LINUX_SWIOTLB_H */