xref: /linux-6.15/include/linux/swiotlb.h (revision bb4e9af0)
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 
9 struct device;
10 struct page;
11 struct scatterlist;
12 
13 enum 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 
32 extern void swiotlb_init(int verbose);
33 int swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose);
34 extern unsigned long swiotlb_nr_tbl(void);
35 unsigned long swiotlb_size_or_default(void);
36 extern int swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs);
37 extern void __init swiotlb_update_mem_attributes(void);
38 
39 /*
40  * Enumeration for sync targets
41  */
42 enum dma_sync_target {
43 	SYNC_FOR_CPU = 0,
44 	SYNC_FOR_DEVICE = 1,
45 };
46 
47 extern 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 
53 extern 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 
58 extern 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
64 extern enum swiotlb_force swiotlb_force;
65 extern phys_addr_t io_tlb_start, io_tlb_end;
66 
67 static inline bool is_swiotlb_buffer(phys_addr_t paddr)
68 {
69 	return paddr >= io_tlb_start && paddr < io_tlb_end;
70 }
71 
72 bool 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);
74 void __init swiotlb_exit(void);
75 unsigned int swiotlb_max_segment(void);
76 size_t swiotlb_max_mapping_size(struct device *dev);
77 bool is_swiotlb_active(void);
78 #else
79 #define swiotlb_force SWIOTLB_NO_FORCE
80 static inline bool is_swiotlb_buffer(phys_addr_t paddr)
81 {
82 	return false;
83 }
84 static 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 }
90 static inline void swiotlb_exit(void)
91 {
92 }
93 static inline unsigned int swiotlb_max_segment(void)
94 {
95 	return 0;
96 }
97 static inline size_t swiotlb_max_mapping_size(struct device *dev)
98 {
99 	return SIZE_MAX;
100 }
101 
102 static inline bool is_swiotlb_active(void)
103 {
104 	return false;
105 }
106 #endif /* CONFIG_SWIOTLB */
107 
108 extern void swiotlb_print_info(void);
109 extern void swiotlb_set_max_segment(unsigned int);
110 
111 #endif /* __LINUX_SWIOTLB_H */
112