xref: /linux-6.15/include/linux/io.h (revision e7bc47b1)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Copyright 2006 PathScale, Inc.  All Rights Reserved.
4  */
5 
6 #ifndef _LINUX_IO_H
7 #define _LINUX_IO_H
8 
9 #include <linux/types.h>
10 #include <linux/init.h>
11 #include <linux/bug.h>
12 #include <linux/err.h>
13 #include <asm/io.h>
14 #include <asm/page.h>
15 
16 struct device;
17 struct resource;
18 
19 #ifndef __iowrite32_copy
20 void __iowrite32_copy(void __iomem *to, const void *from, size_t count);
21 #endif
22 
23 void __ioread32_copy(void *to, const void __iomem *from, size_t count);
24 
25 #ifndef __iowrite64_copy
26 void __iowrite64_copy(void __iomem *to, const void *from, size_t count);
27 #endif
28 
29 #ifdef CONFIG_MMU
30 int ioremap_page_range(unsigned long addr, unsigned long end,
31 		       phys_addr_t phys_addr, pgprot_t prot);
32 int vmap_page_range(unsigned long addr, unsigned long end,
33 		    phys_addr_t phys_addr, pgprot_t prot);
34 #else
35 static inline int ioremap_page_range(unsigned long addr, unsigned long end,
36 				     phys_addr_t phys_addr, pgprot_t prot)
37 {
38 	return 0;
39 }
40 static inline int vmap_page_range(unsigned long addr, unsigned long end,
41 				  phys_addr_t phys_addr, pgprot_t prot)
42 {
43 	return 0;
44 }
45 #endif
46 
47 /*
48  * Managed iomap interface
49  */
50 #ifdef CONFIG_HAS_IOPORT_MAP
51 void __iomem * devm_ioport_map(struct device *dev, unsigned long port,
52 			       unsigned int nr);
53 void devm_ioport_unmap(struct device *dev, void __iomem *addr);
54 #else
55 static inline void __iomem *devm_ioport_map(struct device *dev,
56 					     unsigned long port,
57 					     unsigned int nr)
58 {
59 	return NULL;
60 }
61 
62 static inline void devm_ioport_unmap(struct device *dev, void __iomem *addr)
63 {
64 }
65 #endif
66 
67 #define IOMEM_ERR_PTR(err) (__force void __iomem *)ERR_PTR(err)
68 
69 void __iomem *devm_ioremap(struct device *dev, resource_size_t offset,
70 			   resource_size_t size);
71 void __iomem *devm_ioremap_uc(struct device *dev, resource_size_t offset,
72 				   resource_size_t size);
73 void __iomem *devm_ioremap_wc(struct device *dev, resource_size_t offset,
74 				   resource_size_t size);
75 void devm_iounmap(struct device *dev, void __iomem *addr);
76 int check_signature(const volatile void __iomem *io_addr,
77 			const unsigned char *signature, int length);
78 void devm_ioremap_release(struct device *dev, void *res);
79 
80 void *devm_memremap(struct device *dev, resource_size_t offset,
81 		size_t size, unsigned long flags);
82 void devm_memunmap(struct device *dev, void *addr);
83 
84 /* architectures can override this */
85 pgprot_t __init early_memremap_pgprot_adjust(resource_size_t phys_addr,
86 					unsigned long size, pgprot_t prot);
87 
88 
89 #ifdef CONFIG_PCI
90 /*
91  * The PCI specifications (Rev 3.0, 3.2.5 "Transaction Ordering and
92  * Posting") mandate non-posted configuration transactions. This default
93  * implementation attempts to use the ioremap_np() API to provide this
94  * on arches that support it, and falls back to ioremap() on those that
95  * don't. Overriding this function is deprecated; arches that properly
96  * support non-posted accesses should implement ioremap_np() instead, which
97  * this default implementation can then use to return mappings compliant with
98  * the PCI specification.
99  */
100 #ifndef pci_remap_cfgspace
101 #define pci_remap_cfgspace pci_remap_cfgspace
102 static inline void __iomem *pci_remap_cfgspace(phys_addr_t offset,
103 					       size_t size)
104 {
105 	return ioremap_np(offset, size) ?: ioremap(offset, size);
106 }
107 #endif
108 #endif
109 
110 /*
111  * Some systems do not have legacy ISA devices.
112  * /dev/port is not a valid interface on these systems.
113  * So for those archs, <asm/io.h> should define the following symbol.
114  */
115 #ifndef arch_has_dev_port
116 #define arch_has_dev_port()     (1)
117 #endif
118 
119 /*
120  * Some systems (x86 without PAT) have a somewhat reliable way to mark a
121  * physical address range such that uncached mappings will actually
122  * end up write-combining.  This facility should be used in conjunction
123  * with pgprot_writecombine, ioremap-wc, or set_memory_wc, since it has
124  * no effect if the per-page mechanisms are functional.
125  * (On x86 without PAT, these functions manipulate MTRRs.)
126  *
127  * arch_phys_del_wc(0) or arch_phys_del_wc(any error code) is guaranteed
128  * to have no effect.
129  */
130 #ifndef arch_phys_wc_add
131 static inline int __must_check arch_phys_wc_add(unsigned long base,
132 						unsigned long size)
133 {
134 	return 0;  /* It worked (i.e. did nothing). */
135 }
136 
137 static inline void arch_phys_wc_del(int handle)
138 {
139 }
140 
141 #define arch_phys_wc_add arch_phys_wc_add
142 #ifndef arch_phys_wc_index
143 static inline int arch_phys_wc_index(int handle)
144 {
145 	return -1;
146 }
147 #define arch_phys_wc_index arch_phys_wc_index
148 #endif
149 #endif
150 
151 int devm_arch_phys_wc_add(struct device *dev, unsigned long base, unsigned long size);
152 
153 enum {
154 	/* See memremap() kernel-doc for usage description... */
155 	MEMREMAP_WB = 1 << 0,
156 	MEMREMAP_WT = 1 << 1,
157 	MEMREMAP_WC = 1 << 2,
158 	MEMREMAP_ENC = 1 << 3,
159 	MEMREMAP_DEC = 1 << 4,
160 };
161 
162 void *memremap(resource_size_t offset, size_t size, unsigned long flags);
163 void memunmap(void *addr);
164 
165 /*
166  * On x86 PAT systems we have memory tracking that keeps track of
167  * the allowed mappings on memory ranges. This tracking works for
168  * all the in-kernel mapping APIs (ioremap*), but where the user
169  * wishes to map a range from a physical device into user memory
170  * the tracking won't be updated. This API is to be used by
171  * drivers which remap physical device pages into userspace,
172  * and wants to make sure they are mapped WC and not UC.
173  */
174 #ifndef arch_io_reserve_memtype_wc
175 static inline int arch_io_reserve_memtype_wc(resource_size_t base,
176 					     resource_size_t size)
177 {
178 	return 0;
179 }
180 
181 static inline void arch_io_free_memtype_wc(resource_size_t base,
182 					   resource_size_t size)
183 {
184 }
185 #endif
186 
187 int devm_arch_io_reserve_memtype_wc(struct device *dev, resource_size_t start,
188 				    resource_size_t size);
189 
190 #endif /* _LINUX_IO_H */
191