xref: /linux/lib/iomap.c (revision f79e4d5f92a129a1159c973735007d4ddc8541f3)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Implement the default iomap interfaces
4  *
5  * (C) Copyright 2004 Linus Torvalds
6  */
7 #include <linux/pci.h>
8 #include <linux/io.h>
9 
10 #include <linux/export.h>
11 
12 /*
13  * Read/write from/to an (offsettable) iomem cookie. It might be a PIO
14  * access or a MMIO access, these functions don't care. The info is
15  * encoded in the hardware mapping set up by the mapping functions
16  * (or the cookie itself, depending on implementation and hw).
17  *
18  * The generic routines don't assume any hardware mappings, and just
19  * encode the PIO/MMIO as part of the cookie. They coldly assume that
20  * the MMIO IO mappings are not in the low address range.
21  *
22  * Architectures for which this is not true can't use this generic
23  * implementation and should do their own copy.
24  */
25 
26 #ifndef HAVE_ARCH_PIO_SIZE
27 /*
28  * We encode the physical PIO addresses (0-0xffff) into the
29  * pointer by offsetting them with a constant (0x10000) and
30  * assuming that all the low addresses are always PIO. That means
31  * we can do some sanity checks on the low bits, and don't
32  * need to just take things for granted.
33  */
34 #define PIO_OFFSET	0x10000UL
35 #define PIO_MASK	0x0ffffUL
36 #define PIO_RESERVED	0x40000UL
37 #endif
38 
39 static void bad_io_access(unsigned long port, const char *access)
40 {
41 	static int count = 10;
42 	if (count) {
43 		count--;
44 		WARN(1, KERN_ERR "Bad IO access at port %#lx (%s)\n", port, access);
45 	}
46 }
47 
48 /*
49  * Ugly macros are a way of life.
50  */
51 #define IO_COND(addr, is_pio, is_mmio) do {			\
52 	unsigned long port = (unsigned long __force)addr;	\
53 	if (port >= PIO_RESERVED) {				\
54 		is_mmio;					\
55 	} else if (port > PIO_OFFSET) {				\
56 		port &= PIO_MASK;				\
57 		is_pio;						\
58 	} else							\
59 		bad_io_access(port, #is_pio );			\
60 } while (0)
61 
62 #ifndef pio_read16be
63 #define pio_read16be(port) swab16(inw(port))
64 #define pio_read32be(port) swab32(inl(port))
65 #endif
66 
67 #ifndef mmio_read16be
68 #define mmio_read16be(addr) be16_to_cpu(__raw_readw(addr))
69 #define mmio_read32be(addr) be32_to_cpu(__raw_readl(addr))
70 #endif
71 
72 unsigned int ioread8(void __iomem *addr)
73 {
74 	IO_COND(addr, return inb(port), return readb(addr));
75 	return 0xff;
76 }
77 unsigned int ioread16(void __iomem *addr)
78 {
79 	IO_COND(addr, return inw(port), return readw(addr));
80 	return 0xffff;
81 }
82 unsigned int ioread16be(void __iomem *addr)
83 {
84 	IO_COND(addr, return pio_read16be(port), return mmio_read16be(addr));
85 	return 0xffff;
86 }
87 unsigned int ioread32(void __iomem *addr)
88 {
89 	IO_COND(addr, return inl(port), return readl(addr));
90 	return 0xffffffff;
91 }
92 unsigned int ioread32be(void __iomem *addr)
93 {
94 	IO_COND(addr, return pio_read32be(port), return mmio_read32be(addr));
95 	return 0xffffffff;
96 }
97 EXPORT_SYMBOL(ioread8);
98 EXPORT_SYMBOL(ioread16);
99 EXPORT_SYMBOL(ioread16be);
100 EXPORT_SYMBOL(ioread32);
101 EXPORT_SYMBOL(ioread32be);
102 
103 #ifndef pio_write16be
104 #define pio_write16be(val,port) outw(swab16(val),port)
105 #define pio_write32be(val,port) outl(swab32(val),port)
106 #endif
107 
108 #ifndef mmio_write16be
109 #define mmio_write16be(val,port) __raw_writew(be16_to_cpu(val),port)
110 #define mmio_write32be(val,port) __raw_writel(be32_to_cpu(val),port)
111 #endif
112 
113 void iowrite8(u8 val, void __iomem *addr)
114 {
115 	IO_COND(addr, outb(val,port), writeb(val, addr));
116 }
117 void iowrite16(u16 val, void __iomem *addr)
118 {
119 	IO_COND(addr, outw(val,port), writew(val, addr));
120 }
121 void iowrite16be(u16 val, void __iomem *addr)
122 {
123 	IO_COND(addr, pio_write16be(val,port), mmio_write16be(val, addr));
124 }
125 void iowrite32(u32 val, void __iomem *addr)
126 {
127 	IO_COND(addr, outl(val,port), writel(val, addr));
128 }
129 void iowrite32be(u32 val, void __iomem *addr)
130 {
131 	IO_COND(addr, pio_write32be(val,port), mmio_write32be(val, addr));
132 }
133 EXPORT_SYMBOL(iowrite8);
134 EXPORT_SYMBOL(iowrite16);
135 EXPORT_SYMBOL(iowrite16be);
136 EXPORT_SYMBOL(iowrite32);
137 EXPORT_SYMBOL(iowrite32be);
138 
139 /*
140  * These are the "repeat MMIO read/write" functions.
141  * Note the "__raw" accesses, since we don't want to
142  * convert to CPU byte order. We write in "IO byte
143  * order" (we also don't have IO barriers).
144  */
145 #ifndef mmio_insb
146 static inline void mmio_insb(void __iomem *addr, u8 *dst, int count)
147 {
148 	while (--count >= 0) {
149 		u8 data = __raw_readb(addr);
150 		*dst = data;
151 		dst++;
152 	}
153 }
154 static inline void mmio_insw(void __iomem *addr, u16 *dst, int count)
155 {
156 	while (--count >= 0) {
157 		u16 data = __raw_readw(addr);
158 		*dst = data;
159 		dst++;
160 	}
161 }
162 static inline void mmio_insl(void __iomem *addr, u32 *dst, int count)
163 {
164 	while (--count >= 0) {
165 		u32 data = __raw_readl(addr);
166 		*dst = data;
167 		dst++;
168 	}
169 }
170 #endif
171 
172 #ifndef mmio_outsb
173 static inline void mmio_outsb(void __iomem *addr, const u8 *src, int count)
174 {
175 	while (--count >= 0) {
176 		__raw_writeb(*src, addr);
177 		src++;
178 	}
179 }
180 static inline void mmio_outsw(void __iomem *addr, const u16 *src, int count)
181 {
182 	while (--count >= 0) {
183 		__raw_writew(*src, addr);
184 		src++;
185 	}
186 }
187 static inline void mmio_outsl(void __iomem *addr, const u32 *src, int count)
188 {
189 	while (--count >= 0) {
190 		__raw_writel(*src, addr);
191 		src++;
192 	}
193 }
194 #endif
195 
196 void ioread8_rep(void __iomem *addr, void *dst, unsigned long count)
197 {
198 	IO_COND(addr, insb(port,dst,count), mmio_insb(addr, dst, count));
199 }
200 void ioread16_rep(void __iomem *addr, void *dst, unsigned long count)
201 {
202 	IO_COND(addr, insw(port,dst,count), mmio_insw(addr, dst, count));
203 }
204 void ioread32_rep(void __iomem *addr, void *dst, unsigned long count)
205 {
206 	IO_COND(addr, insl(port,dst,count), mmio_insl(addr, dst, count));
207 }
208 EXPORT_SYMBOL(ioread8_rep);
209 EXPORT_SYMBOL(ioread16_rep);
210 EXPORT_SYMBOL(ioread32_rep);
211 
212 void iowrite8_rep(void __iomem *addr, const void *src, unsigned long count)
213 {
214 	IO_COND(addr, outsb(port, src, count), mmio_outsb(addr, src, count));
215 }
216 void iowrite16_rep(void __iomem *addr, const void *src, unsigned long count)
217 {
218 	IO_COND(addr, outsw(port, src, count), mmio_outsw(addr, src, count));
219 }
220 void iowrite32_rep(void __iomem *addr, const void *src, unsigned long count)
221 {
222 	IO_COND(addr, outsl(port, src,count), mmio_outsl(addr, src, count));
223 }
224 EXPORT_SYMBOL(iowrite8_rep);
225 EXPORT_SYMBOL(iowrite16_rep);
226 EXPORT_SYMBOL(iowrite32_rep);
227 
228 #ifdef CONFIG_HAS_IOPORT_MAP
229 /* Create a virtual mapping cookie for an IO port range */
230 void __iomem *ioport_map(unsigned long port, unsigned int nr)
231 {
232 	if (port > PIO_MASK)
233 		return NULL;
234 	return (void __iomem *) (unsigned long) (port + PIO_OFFSET);
235 }
236 
237 void ioport_unmap(void __iomem *addr)
238 {
239 	/* Nothing to do */
240 }
241 EXPORT_SYMBOL(ioport_map);
242 EXPORT_SYMBOL(ioport_unmap);
243 #endif /* CONFIG_HAS_IOPORT_MAP */
244 
245 #ifdef CONFIG_PCI
246 /* Hide the details if this is a MMIO or PIO address space and just do what
247  * you expect in the correct way. */
248 void pci_iounmap(struct pci_dev *dev, void __iomem * addr)
249 {
250 	IO_COND(addr, /* nothing */, iounmap(addr));
251 }
252 EXPORT_SYMBOL(pci_iounmap);
253 #endif /* CONFIG_PCI */
254