xref: /linux-6.15/include/linux/io.h (revision 2494fce2)
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/sizes.h>
10 #include <linux/types.h>
11 #include <linux/init.h>
12 #include <asm/io.h>
13 #include <asm/page.h>
14 
15 struct device;
16 
17 #ifndef __iowrite32_copy
18 void __iowrite32_copy(void __iomem *to, const void *from, size_t count);
19 #endif
20 
21 void __ioread32_copy(void *to, const void __iomem *from, size_t count);
22 
23 #ifndef __iowrite64_copy
24 void __iowrite64_copy(void __iomem *to, const void *from, size_t count);
25 #endif
26 
27 #ifdef CONFIG_MMU
28 int ioremap_page_range(unsigned long addr, unsigned long end,
29 		       phys_addr_t phys_addr, pgprot_t prot);
30 int vmap_page_range(unsigned long addr, unsigned long end,
31 		    phys_addr_t phys_addr, pgprot_t prot);
32 #else
33 static inline int ioremap_page_range(unsigned long addr, unsigned long end,
34 				     phys_addr_t phys_addr, pgprot_t prot)
35 {
36 	return 0;
37 }
38 static inline int vmap_page_range(unsigned long addr, unsigned long end,
39 				  phys_addr_t phys_addr, pgprot_t prot)
40 {
41 	return 0;
42 }
43 #endif
44 
45 /*
46  * Managed iomap interface
47  */
48 #ifdef CONFIG_HAS_IOPORT_MAP
49 void __iomem * devm_ioport_map(struct device *dev, unsigned long port,
50 			       unsigned int nr);
51 void devm_ioport_unmap(struct device *dev, void __iomem *addr);
52 #else
53 static inline void __iomem *devm_ioport_map(struct device *dev,
54 					     unsigned long port,
55 					     unsigned int nr)
56 {
57 	return NULL;
58 }
59 
60 static inline void devm_ioport_unmap(struct device *dev, void __iomem *addr)
61 {
62 }
63 #endif
64 
65 #define IOMEM_ERR_PTR(err) (__force void __iomem *)ERR_PTR(err)
66 
67 void __iomem *devm_ioremap(struct device *dev, resource_size_t offset,
68 			   resource_size_t size);
69 void __iomem *devm_ioremap_uc(struct device *dev, resource_size_t offset,
70 				   resource_size_t size);
71 void __iomem *devm_ioremap_wc(struct device *dev, resource_size_t offset,
72 				   resource_size_t size);
73 void devm_iounmap(struct device *dev, void __iomem *addr);
74 int check_signature(const volatile void __iomem *io_addr,
75 			const unsigned char *signature, int length);
76 void devm_ioremap_release(struct device *dev, void *res);
77 
78 void *devm_memremap(struct device *dev, resource_size_t offset,
79 		size_t size, unsigned long flags);
80 void devm_memunmap(struct device *dev, void *addr);
81 
82 /* architectures can override this */
83 pgprot_t __init early_memremap_pgprot_adjust(resource_size_t phys_addr,
84 					unsigned long size, pgprot_t prot);
85 
86 
87 #ifdef CONFIG_PCI
88 /*
89  * The PCI specifications (Rev 3.0, 3.2.5 "Transaction Ordering and
90  * Posting") mandate non-posted configuration transactions. This default
91  * implementation attempts to use the ioremap_np() API to provide this
92  * on arches that support it, and falls back to ioremap() on those that
93  * don't. Overriding this function is deprecated; arches that properly
94  * support non-posted accesses should implement ioremap_np() instead, which
95  * this default implementation can then use to return mappings compliant with
96  * the PCI specification.
97  */
98 #ifndef pci_remap_cfgspace
99 #define pci_remap_cfgspace pci_remap_cfgspace
100 static inline void __iomem *pci_remap_cfgspace(phys_addr_t offset,
101 					       size_t size)
102 {
103 	return ioremap_np(offset, size) ?: ioremap(offset, size);
104 }
105 #endif
106 #endif
107 
108 /*
109  * Some systems do not have legacy ISA devices.
110  * /dev/port is not a valid interface on these systems.
111  * So for those archs, <asm/io.h> should define the following symbol.
112  */
113 #ifndef arch_has_dev_port
114 #define arch_has_dev_port()     (1)
115 #endif
116 
117 /*
118  * Some systems (x86 without PAT) have a somewhat reliable way to mark a
119  * physical address range such that uncached mappings will actually
120  * end up write-combining.  This facility should be used in conjunction
121  * with pgprot_writecombine, ioremap-wc, or set_memory_wc, since it has
122  * no effect if the per-page mechanisms are functional.
123  * (On x86 without PAT, these functions manipulate MTRRs.)
124  *
125  * arch_phys_del_wc(0) or arch_phys_del_wc(any error code) is guaranteed
126  * to have no effect.
127  */
128 #ifndef arch_phys_wc_add
129 static inline int __must_check arch_phys_wc_add(unsigned long base,
130 						unsigned long size)
131 {
132 	return 0;  /* It worked (i.e. did nothing). */
133 }
134 
135 static inline void arch_phys_wc_del(int handle)
136 {
137 }
138 
139 #define arch_phys_wc_add arch_phys_wc_add
140 #ifndef arch_phys_wc_index
141 static inline int arch_phys_wc_index(int handle)
142 {
143 	return -1;
144 }
145 #define arch_phys_wc_index arch_phys_wc_index
146 #endif
147 #endif
148 
149 int devm_arch_phys_wc_add(struct device *dev, unsigned long base, unsigned long size);
150 
151 enum {
152 	/* See memremap() kernel-doc for usage description... */
153 	MEMREMAP_WB = 1 << 0,
154 	MEMREMAP_WT = 1 << 1,
155 	MEMREMAP_WC = 1 << 2,
156 	MEMREMAP_ENC = 1 << 3,
157 	MEMREMAP_DEC = 1 << 4,
158 };
159 
160 void *memremap(resource_size_t offset, size_t size, unsigned long flags);
161 void memunmap(void *addr);
162 
163 /*
164  * On x86 PAT systems we have memory tracking that keeps track of
165  * the allowed mappings on memory ranges. This tracking works for
166  * all the in-kernel mapping APIs (ioremap*), but where the user
167  * wishes to map a range from a physical device into user memory
168  * the tracking won't be updated. This API is to be used by
169  * drivers which remap physical device pages into userspace,
170  * and wants to make sure they are mapped WC and not UC.
171  */
172 #ifndef arch_io_reserve_memtype_wc
173 static inline int arch_io_reserve_memtype_wc(resource_size_t base,
174 					     resource_size_t size)
175 {
176 	return 0;
177 }
178 
179 static inline void arch_io_free_memtype_wc(resource_size_t base,
180 					   resource_size_t size)
181 {
182 }
183 #endif
184 
185 int devm_arch_io_reserve_memtype_wc(struct device *dev, resource_size_t start,
186 				    resource_size_t size);
187 
188 #endif /* _LINUX_IO_H */
189