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 #include <linux/spinlock.h>
10
11 struct device;
12 struct page;
13 struct scatterlist;
14
15 enum swiotlb_force {
16 SWIOTLB_NORMAL, /* Default - depending on HW DMA mask etc. */
17 SWIOTLB_FORCE, /* swiotlb=force */
18 SWIOTLB_NO_FORCE, /* swiotlb=noforce */
19 };
20
21 /*
22 * Maximum allowable number of contiguous slabs to map,
23 * must be a power of 2. What is the appropriate value ?
24 * The complexity of {map,unmap}_single is linearly dependent on this value.
25 */
26 #define IO_TLB_SEGSIZE 128
27
28 /*
29 * log of the size of each IO TLB slab. The number of slabs is command line
30 * controllable.
31 */
32 #define IO_TLB_SHIFT 11
33 #define IO_TLB_SIZE (1 << IO_TLB_SHIFT)
34
35 /* default to 64MB */
36 #define IO_TLB_DEFAULT_SIZE (64UL<<20)
37
38 extern void swiotlb_init(int verbose);
39 int swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose);
40 unsigned long swiotlb_size_or_default(void);
41 extern int swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs);
42 extern int swiotlb_late_init_with_default_size(size_t default_size);
43 extern void __init swiotlb_update_mem_attributes(void);
44
45 phys_addr_t swiotlb_tbl_map_single(struct device *hwdev, phys_addr_t phys,
46 size_t mapping_size, size_t alloc_size,
47 enum dma_data_direction dir, unsigned long attrs);
48
49 extern void swiotlb_tbl_unmap_single(struct device *hwdev,
50 phys_addr_t tlb_addr,
51 size_t mapping_size,
52 enum dma_data_direction dir,
53 unsigned long attrs);
54
55 void swiotlb_sync_single_for_device(struct device *dev, phys_addr_t tlb_addr,
56 size_t size, enum dma_data_direction dir);
57 void swiotlb_sync_single_for_cpu(struct device *dev, phys_addr_t tlb_addr,
58 size_t size, enum dma_data_direction dir);
59 dma_addr_t swiotlb_map(struct device *dev, phys_addr_t phys,
60 size_t size, enum dma_data_direction dir, unsigned long attrs);
61
62 #ifdef CONFIG_SWIOTLB
63 extern enum swiotlb_force swiotlb_force;
64
65 /**
66 * struct io_tlb_mem - IO TLB Memory Pool Descriptor
67 *
68 * @start: The start address of the swiotlb memory pool. Used to do a quick
69 * range check to see if the memory was in fact allocated by this
70 * API.
71 * @end: The end address of the swiotlb memory pool. Used to do a quick
72 * range check to see if the memory was in fact allocated by this
73 * API.
74 * @nslabs: The number of IO TLB blocks (in groups of 64) between @start and
75 * @end. This is command line adjustable via setup_io_tlb_npages.
76 * @used: The number of used IO TLB block.
77 * @list: The free list describing the number of free entries available
78 * from each index.
79 * @index: The index to start searching in the next round.
80 * @orig_addr: The original address corresponding to a mapped entry.
81 * @alloc_size: Size of the allocated buffer.
82 * @lock: The lock to protect the above data structures in the map and
83 * unmap calls.
84 * @debugfs: The dentry to debugfs.
85 * @late_alloc: %true if allocated using the page allocator
86 */
87 struct io_tlb_mem {
88 phys_addr_t start;
89 phys_addr_t end;
90 unsigned long nslabs;
91 unsigned long used;
92 unsigned int index;
93 spinlock_t lock;
94 struct dentry *debugfs;
95 bool late_alloc;
96 struct io_tlb_slot {
97 phys_addr_t orig_addr;
98 size_t alloc_size;
99 unsigned int list;
100 } slots[];
101 };
102 extern struct io_tlb_mem *io_tlb_default_mem;
103
is_swiotlb_buffer(phys_addr_t paddr)104 static inline bool is_swiotlb_buffer(phys_addr_t paddr)
105 {
106 struct io_tlb_mem *mem = io_tlb_default_mem;
107
108 return mem && paddr >= mem->start && paddr < mem->end;
109 }
110
111 void __init swiotlb_exit(void);
112 unsigned int swiotlb_max_segment(void);
113 size_t swiotlb_max_mapping_size(struct device *dev);
114 bool is_swiotlb_active(void);
115 void __init swiotlb_adjust_size(unsigned long size);
116 #else
117 #define swiotlb_force SWIOTLB_NO_FORCE
is_swiotlb_buffer(phys_addr_t paddr)118 static inline bool is_swiotlb_buffer(phys_addr_t paddr)
119 {
120 return false;
121 }
swiotlb_exit(void)122 static inline void swiotlb_exit(void)
123 {
124 }
swiotlb_max_segment(void)125 static inline unsigned int swiotlb_max_segment(void)
126 {
127 return 0;
128 }
swiotlb_max_mapping_size(struct device * dev)129 static inline size_t swiotlb_max_mapping_size(struct device *dev)
130 {
131 return SIZE_MAX;
132 }
133
is_swiotlb_active(void)134 static inline bool is_swiotlb_active(void)
135 {
136 return false;
137 }
138
swiotlb_adjust_size(unsigned long size)139 static inline void swiotlb_adjust_size(unsigned long size)
140 {
141 }
142 #endif /* CONFIG_SWIOTLB */
143
144 extern void swiotlb_print_info(void);
145 extern void swiotlb_set_max_segment(unsigned int);
146
147 #endif /* __LINUX_SWIOTLB_H */
148