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

source code of linux/include/linux/io.h