xref: /linux-6.15/include/linux/io.h (revision 02cc2ccf)
1 /*
2  * Copyright 2006 PathScale, Inc.  All Rights Reserved.
3  *
4  * This file is free software; you can redistribute it and/or modify
5  * it under the terms of version 2 of the GNU General Public License
6  * as published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope that it will be useful,
9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11  * GNU General Public License for more details.
12  *
13  * You should have received a copy of the GNU General Public License
14  * along with this program; if not, write to the Free Software Foundation,
15  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
16  */
17 
18 #ifndef _LINUX_IO_H
19 #define _LINUX_IO_H
20 
21 #include <linux/types.h>
22 #include <linux/init.h>
23 #include <asm/io.h>
24 #include <asm/page.h>
25 
26 struct device;
27 
28 __visible void __iowrite32_copy(void __iomem *to, const void *from, size_t count);
29 void __iowrite64_copy(void __iomem *to, const void *from, size_t count);
30 
31 #ifdef CONFIG_MMU
32 int ioremap_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 #endif
41 
42 #ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
43 void __init ioremap_huge_init(void);
44 int arch_ioremap_pud_supported(void);
45 int arch_ioremap_pmd_supported(void);
46 #else
47 static inline void ioremap_huge_init(void) { }
48 #endif
49 
50 /*
51  * Managed iomap interface
52  */
53 #ifdef CONFIG_HAS_IOPORT_MAP
54 void __iomem * devm_ioport_map(struct device *dev, unsigned long port,
55 			       unsigned int nr);
56 void devm_ioport_unmap(struct device *dev, void __iomem *addr);
57 #else
58 static inline void __iomem *devm_ioport_map(struct device *dev,
59 					     unsigned long port,
60 					     unsigned int nr)
61 {
62 	return NULL;
63 }
64 
65 static inline void devm_ioport_unmap(struct device *dev, void __iomem *addr)
66 {
67 }
68 #endif
69 
70 #define IOMEM_ERR_PTR(err) (__force void __iomem *)ERR_PTR(err)
71 
72 void __iomem *devm_ioremap(struct device *dev, resource_size_t offset,
73 			   resource_size_t size);
74 void __iomem *devm_ioremap_nocache(struct device *dev, resource_size_t offset,
75 				   resource_size_t size);
76 void __iomem *devm_ioremap_wc(struct device *dev, resource_size_t offset,
77 				   resource_size_t size);
78 void devm_iounmap(struct device *dev, void __iomem *addr);
79 int check_signature(const volatile void __iomem *io_addr,
80 			const unsigned char *signature, int length);
81 void devm_ioremap_release(struct device *dev, void *res);
82 
83 /*
84  * Some systems do not have legacy ISA devices.
85  * /dev/port is not a valid interface on these systems.
86  * So for those archs, <asm/io.h> should define the following symbol.
87  */
88 #ifndef arch_has_dev_port
89 #define arch_has_dev_port()     (1)
90 #endif
91 
92 /*
93  * Some systems (x86 without PAT) have a somewhat reliable way to mark a
94  * physical address range such that uncached mappings will actually
95  * end up write-combining.  This facility should be used in conjunction
96  * with pgprot_writecombine, ioremap-wc, or set_memory_wc, since it has
97  * no effect if the per-page mechanisms are functional.
98  * (On x86 without PAT, these functions manipulate MTRRs.)
99  *
100  * arch_phys_del_wc(0) or arch_phys_del_wc(any error code) is guaranteed
101  * to have no effect.
102  */
103 #ifndef arch_phys_wc_add
104 static inline int __must_check arch_phys_wc_add(unsigned long base,
105 						unsigned long size)
106 {
107 	return 0;  /* It worked (i.e. did nothing). */
108 }
109 
110 static inline void arch_phys_wc_del(int handle)
111 {
112 }
113 
114 #define arch_phys_wc_add arch_phys_wc_add
115 #ifndef arch_phys_wc_index
116 static inline int arch_phys_wc_index(int handle)
117 {
118 	return -1;
119 }
120 #define arch_phys_wc_index arch_phys_wc_index
121 #endif
122 #endif
123 
124 #endif /* _LINUX_IO_H */
125