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 #ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
35 void __init ioremap_huge_init(void);
36 int arch_ioremap_p4d_supported(void);
37 int arch_ioremap_pud_supported(void);
38 int arch_ioremap_pmd_supported(void);
39 #else
ioremap_huge_init(void)40 static inline void ioremap_huge_init(void) { }
41 #endif
42 
43 /*
44  * Managed iomap interface
45  */
46 #ifdef CONFIG_HAS_IOPORT_MAP
47 void __iomem * devm_ioport_map(struct device *dev, unsigned long port,
48 			       unsigned int nr);
49 void devm_ioport_unmap(struct device *dev, void __iomem *addr);
50 #else
devm_ioport_map(struct device * dev,unsigned long port,unsigned int nr)51 static inline void __iomem *devm_ioport_map(struct device *dev,
52 					     unsigned long port,
53 					     unsigned int nr)
54 {
55 	return NULL;
56 }
57 
devm_ioport_unmap(struct device * dev,void __iomem * addr)58 static inline void devm_ioport_unmap(struct device *dev, void __iomem *addr)
59 {
60 }
61 #endif
62 
63 #define IOMEM_ERR_PTR(err) (__force void __iomem *)ERR_PTR(err)
64 
65 void __iomem *devm_ioremap(struct device *dev, resource_size_t offset,
66 			   resource_size_t size);
67 void __iomem *devm_ioremap_uc(struct device *dev, resource_size_t offset,
68 				   resource_size_t size);
69 void __iomem *devm_ioremap_wc(struct device *dev, resource_size_t offset,
70 				   resource_size_t size);
71 void devm_iounmap(struct device *dev, void __iomem *addr);
72 int check_signature(const volatile void __iomem *io_addr,
73 			const unsigned char *signature, int length);
74 void devm_ioremap_release(struct device *dev, void *res);
75 
76 void *devm_memremap(struct device *dev, resource_size_t offset,
77 		size_t size, unsigned long flags);
78 void devm_memunmap(struct device *dev, void *addr);
79 
80 #ifdef CONFIG_PCI
81 /*
82  * The PCI specifications (Rev 3.0, 3.2.5 "Transaction Ordering and
83  * Posting") mandate non-posted configuration transactions. There is
84  * no ioremap API in the kernel that can guarantee non-posted write
85  * semantics across arches so provide a default implementation for
86  * mapping PCI config space that defaults to ioremap(); arches
87  * should override it if they have memory mapping implementations that
88  * guarantee non-posted writes semantics to make the memory mapping
89  * compliant with the PCI specification.
90  */
91 #ifndef pci_remap_cfgspace
92 #define pci_remap_cfgspace pci_remap_cfgspace
pci_remap_cfgspace(phys_addr_t offset,size_t size)93 static inline void __iomem *pci_remap_cfgspace(phys_addr_t offset,
94 					       size_t size)
95 {
96 	return ioremap(offset, size);
97 }
98 #endif
99 #endif
100 
101 /*
102  * Some systems do not have legacy ISA devices.
103  * /dev/port is not a valid interface on these systems.
104  * So for those archs, <asm/io.h> should define the following symbol.
105  */
106 #ifndef arch_has_dev_port
107 #define arch_has_dev_port()     (1)
108 #endif
109 
110 /*
111  * Some systems (x86 without PAT) have a somewhat reliable way to mark a
112  * physical address range such that uncached mappings will actually
113  * end up write-combining.  This facility should be used in conjunction
114  * with pgprot_writecombine, ioremap-wc, or set_memory_wc, since it has
115  * no effect if the per-page mechanisms are functional.
116  * (On x86 without PAT, these functions manipulate MTRRs.)
117  *
118  * arch_phys_del_wc(0) or arch_phys_del_wc(any error code) is guaranteed
119  * to have no effect.
120  */
121 #ifndef arch_phys_wc_add
arch_phys_wc_add(unsigned long base,unsigned long size)122 static inline int __must_check arch_phys_wc_add(unsigned long base,
123 						unsigned long size)
124 {
125 	return 0;  /* It worked (i.e. did nothing). */
126 }
127 
arch_phys_wc_del(int handle)128 static inline void arch_phys_wc_del(int handle)
129 {
130 }
131 
132 #define arch_phys_wc_add arch_phys_wc_add
133 #ifndef arch_phys_wc_index
arch_phys_wc_index(int handle)134 static inline int arch_phys_wc_index(int handle)
135 {
136 	return -1;
137 }
138 #define arch_phys_wc_index arch_phys_wc_index
139 #endif
140 #endif
141 
142 enum {
143 	/* See memremap() kernel-doc for usage description... */
144 	MEMREMAP_WB = 1 << 0,
145 	MEMREMAP_WT = 1 << 1,
146 	MEMREMAP_WC = 1 << 2,
147 	MEMREMAP_ENC = 1 << 3,
148 	MEMREMAP_DEC = 1 << 4,
149 };
150 
151 void *memremap(resource_size_t offset, size_t size, unsigned long flags);
152 void memunmap(void *addr);
153 
154 /*
155  * On x86 PAT systems we have memory tracking that keeps track of
156  * the allowed mappings on memory ranges. This tracking works for
157  * all the in-kernel mapping APIs (ioremap*), but where the user
158  * wishes to map a range from a physical device into user memory
159  * the tracking won't be updated. This API is to be used by
160  * drivers which remap physical device pages into userspace,
161  * and wants to make sure they are mapped WC and not UC.
162  */
163 #ifndef arch_io_reserve_memtype_wc
arch_io_reserve_memtype_wc(resource_size_t base,resource_size_t size)164 static inline int arch_io_reserve_memtype_wc(resource_size_t base,
165 					     resource_size_t size)
166 {
167 	return 0;
168 }
169 
arch_io_free_memtype_wc(resource_size_t base,resource_size_t size)170 static inline void arch_io_free_memtype_wc(resource_size_t base,
171 					   resource_size_t size)
172 {
173 }
174 #endif
175 
176 #endif /* _LINUX_IO_H */
177