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, 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 */