xref: /openbmc/linux/include/linux/io.h (revision 4d312ac0)
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 __visible void __iowrite32_copy(void __iomem *to, const void *from, size_t count);
20 void __ioread32_copy(void *to, const void __iomem *from, size_t count);
21 void __iowrite64_copy(void __iomem *to, const void *from, size_t count);
22 
23 #ifdef CONFIG_MMU
24 int ioremap_page_range(unsigned long addr, unsigned long end,
25 		       phys_addr_t phys_addr, pgprot_t prot);
26 #else
ioremap_page_range(unsigned long addr,unsigned long end,phys_addr_t phys_addr,pgprot_t prot)27 static 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
38 void __iomem * devm_ioport_map(struct device *dev, unsigned long port,
39 			       unsigned int nr);
40 void devm_ioport_unmap(struct device *dev, void __iomem *addr);
41 #else
devm_ioport_map(struct device * dev,unsigned long port,unsigned int nr)42 static inline void __iomem *devm_ioport_map(struct device *dev,
43 					     unsigned long port,
44 					     unsigned int nr)
45 {
46 	return NULL;
47 }
48 
devm_ioport_unmap(struct device * dev,void __iomem * addr)49 static 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 
56 void __iomem *devm_ioremap(struct device *dev, resource_size_t offset,
57 			   resource_size_t size);
58 void __iomem *devm_ioremap_uc(struct device *dev, resource_size_t offset,
59 				   resource_size_t size);
60 void __iomem *devm_ioremap_wc(struct device *dev, resource_size_t offset,
61 				   resource_size_t size);
62 void devm_iounmap(struct device *dev, void __iomem *addr);
63 int check_signature(const volatile void __iomem *io_addr,
64 			const unsigned char *signature, int length);
65 void devm_ioremap_release(struct device *dev, void *res);
66 
67 void *devm_memremap(struct device *dev, resource_size_t offset,
68 		size_t size, unsigned long flags);
69 void devm_memunmap(struct device *dev, void *addr);
70 
71 /* architectures can override this */
72 pgprot_t __init early_memremap_pgprot_adjust(resource_size_t phys_addr,
73 					unsigned long size, pgprot_t prot);
74 
75 
76 #ifdef CONFIG_PCI
77 /*
78  * The PCI specifications (Rev 3.0, 3.2.5 "Transaction Ordering and
79  * Posting") mandate non-posted configuration transactions. This default
80  * implementation attempts to use the ioremap_np() API to provide this
81  * on arches that support it, and falls back to ioremap() on those that
82  * don't. Overriding this function is deprecated; arches that properly
83  * support non-posted accesses should implement ioremap_np() instead, which
84  * this default implementation can then use to return mappings compliant with
85  * the PCI specification.
86  */
87 #ifndef pci_remap_cfgspace
88 #define pci_remap_cfgspace pci_remap_cfgspace
pci_remap_cfgspace(phys_addr_t offset,size_t size)89 static inline void __iomem *pci_remap_cfgspace(phys_addr_t offset,
90 					       size_t size)
91 {
92 	return ioremap_np(offset, size) ?: ioremap(offset, size);
93 }
94 #endif
95 #endif
96 
97 /*
98  * Some systems do not have legacy ISA devices.
99  * /dev/port is not a valid interface on these systems.
100  * So for those archs, <asm/io.h> should define the following symbol.
101  */
102 #ifndef arch_has_dev_port
103 #define arch_has_dev_port()     (1)
104 #endif
105 
106 /*
107  * Some systems (x86 without PAT) have a somewhat reliable way to mark a
108  * physical address range such that uncached mappings will actually
109  * end up write-combining.  This facility should be used in conjunction
110  * with pgprot_writecombine, ioremap-wc, or set_memory_wc, since it has
111  * no effect if the per-page mechanisms are functional.
112  * (On x86 without PAT, these functions manipulate MTRRs.)
113  *
114  * arch_phys_del_wc(0) or arch_phys_del_wc(any error code) is guaranteed
115  * to have no effect.
116  */
117 #ifndef arch_phys_wc_add
arch_phys_wc_add(unsigned long base,unsigned long size)118 static inline int __must_check arch_phys_wc_add(unsigned long base,
119 						unsigned long size)
120 {
121 	return 0;  /* It worked (i.e. did nothing). */
122 }
123 
arch_phys_wc_del(int handle)124 static inline void arch_phys_wc_del(int handle)
125 {
126 }
127 
128 #define arch_phys_wc_add arch_phys_wc_add
129 #ifndef arch_phys_wc_index
arch_phys_wc_index(int handle)130 static inline int arch_phys_wc_index(int handle)
131 {
132 	return -1;
133 }
134 #define arch_phys_wc_index arch_phys_wc_index
135 #endif
136 #endif
137 
138 int devm_arch_phys_wc_add(struct device *dev, unsigned long base, unsigned long size);
139 
140 enum {
141 	/* See memremap() kernel-doc for usage description... */
142 	MEMREMAP_WB = 1 << 0,
143 	MEMREMAP_WT = 1 << 1,
144 	MEMREMAP_WC = 1 << 2,
145 	MEMREMAP_ENC = 1 << 3,
146 	MEMREMAP_DEC = 1 << 4,
147 };
148 
149 void *memremap(resource_size_t offset, size_t size, unsigned long flags);
150 void memunmap(void *addr);
151 
152 /*
153  * On x86 PAT systems we have memory tracking that keeps track of
154  * the allowed mappings on memory ranges. This tracking works for
155  * all the in-kernel mapping APIs (ioremap*), but where the user
156  * wishes to map a range from a physical device into user memory
157  * the tracking won't be updated. This API is to be used by
158  * drivers which remap physical device pages into userspace,
159  * and wants to make sure they are mapped WC and not UC.
160  */
161 #ifndef arch_io_reserve_memtype_wc
arch_io_reserve_memtype_wc(resource_size_t base,resource_size_t size)162 static inline int arch_io_reserve_memtype_wc(resource_size_t base,
163 					     resource_size_t size)
164 {
165 	return 0;
166 }
167 
arch_io_free_memtype_wc(resource_size_t base,resource_size_t size)168 static inline void arch_io_free_memtype_wc(resource_size_t base,
169 					   resource_size_t size)
170 {
171 }
172 #endif
173 
174 int devm_arch_io_reserve_memtype_wc(struct device *dev, resource_size_t start,
175 				    resource_size_t size);
176 
177 #endif /* _LINUX_IO_H */
178