xref: /openbmc/linux/arch/powerpc/kernel/io.c (revision 0da85d1e)
1 /*
2  * I/O string operations
3  *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
4  *    Copyright (C) 2006 IBM Corporation
5  *
6  * Largely rewritten by Cort Dougan (cort@cs.nmt.edu)
7  * and Paul Mackerras.
8  *
9  * Adapted for iSeries by Mike Corrigan (mikejc@us.ibm.com)
10  * PPC64 updates by Dave Engebretsen (engebret@us.ibm.com)
11  *
12  * Rewritten in C by Stephen Rothwell.
13  *
14  * This program is free software; you can redistribute it and/or
15  * modify it under the terms of the GNU General Public License
16  * as published by the Free Software Foundation; either version
17  * 2 of the License, or (at your option) any later version.
18  */
19 #include <linux/kernel.h>
20 #include <linux/types.h>
21 #include <linux/compiler.h>
22 #include <linux/export.h>
23 
24 #include <asm/io.h>
25 #include <asm/firmware.h>
26 #include <asm/bug.h>
27 
28 /* See definition in io.h */
29 bool isa_io_special;
30 
31 void _insb(const volatile u8 __iomem *port, void *buf, long count)
32 {
33 	u8 *tbuf = buf;
34 	u8 tmp;
35 
36 	if (unlikely(count <= 0))
37 		return;
38 	asm volatile("sync");
39 	do {
40 		tmp = *port;
41 		eieio();
42 		*tbuf++ = tmp;
43 	} while (--count != 0);
44 	asm volatile("twi 0,%0,0; isync" : : "r" (tmp));
45 }
46 EXPORT_SYMBOL(_insb);
47 
48 void _outsb(volatile u8 __iomem *port, const void *buf, long count)
49 {
50 	const u8 *tbuf = buf;
51 
52 	if (unlikely(count <= 0))
53 		return;
54 	asm volatile("sync");
55 	do {
56 		*port = *tbuf++;
57 	} while (--count != 0);
58 	asm volatile("sync");
59 }
60 EXPORT_SYMBOL(_outsb);
61 
62 void _insw_ns(const volatile u16 __iomem *port, void *buf, long count)
63 {
64 	u16 *tbuf = buf;
65 	u16 tmp;
66 
67 	if (unlikely(count <= 0))
68 		return;
69 	asm volatile("sync");
70 	do {
71 		tmp = *port;
72 		eieio();
73 		*tbuf++ = tmp;
74 	} while (--count != 0);
75 	asm volatile("twi 0,%0,0; isync" : : "r" (tmp));
76 }
77 EXPORT_SYMBOL(_insw_ns);
78 
79 void _outsw_ns(volatile u16 __iomem *port, const void *buf, long count)
80 {
81 	const u16 *tbuf = buf;
82 
83 	if (unlikely(count <= 0))
84 		return;
85 	asm volatile("sync");
86 	do {
87 		*port = *tbuf++;
88 	} while (--count != 0);
89 	asm volatile("sync");
90 }
91 EXPORT_SYMBOL(_outsw_ns);
92 
93 void _insl_ns(const volatile u32 __iomem *port, void *buf, long count)
94 {
95 	u32 *tbuf = buf;
96 	u32 tmp;
97 
98 	if (unlikely(count <= 0))
99 		return;
100 	asm volatile("sync");
101 	do {
102 		tmp = *port;
103 		eieio();
104 		*tbuf++ = tmp;
105 	} while (--count != 0);
106 	asm volatile("twi 0,%0,0; isync" : : "r" (tmp));
107 }
108 EXPORT_SYMBOL(_insl_ns);
109 
110 void _outsl_ns(volatile u32 __iomem *port, const void *buf, long count)
111 {
112 	const u32 *tbuf = buf;
113 
114 	if (unlikely(count <= 0))
115 		return;
116 	asm volatile("sync");
117 	do {
118 		*port = *tbuf++;
119 	} while (--count != 0);
120 	asm volatile("sync");
121 }
122 EXPORT_SYMBOL(_outsl_ns);
123 
124 #define IO_CHECK_ALIGN(v,a) ((((unsigned long)(v)) & ((a) - 1)) == 0)
125 
126 notrace void
127 _memset_io(volatile void __iomem *addr, int c, unsigned long n)
128 {
129 	void *p = (void __force *)addr;
130 	u32 lc = c;
131 	lc |= lc << 8;
132 	lc |= lc << 16;
133 
134 	__asm__ __volatile__ ("sync" : : : "memory");
135 	while(n && !IO_CHECK_ALIGN(p, 4)) {
136 		*((volatile u8 *)p) = c;
137 		p++;
138 		n--;
139 	}
140 	while(n >= 4) {
141 		*((volatile u32 *)p) = lc;
142 		p += 4;
143 		n -= 4;
144 	}
145 	while(n) {
146 		*((volatile u8 *)p) = c;
147 		p++;
148 		n--;
149 	}
150 	__asm__ __volatile__ ("sync" : : : "memory");
151 }
152 EXPORT_SYMBOL(_memset_io);
153 
154 void _memcpy_fromio(void *dest, const volatile void __iomem *src,
155 		    unsigned long n)
156 {
157 	void *vsrc = (void __force *) src;
158 
159 	__asm__ __volatile__ ("sync" : : : "memory");
160 	while(n && (!IO_CHECK_ALIGN(vsrc, 4) || !IO_CHECK_ALIGN(dest, 4))) {
161 		*((u8 *)dest) = *((volatile u8 *)vsrc);
162 		eieio();
163 		vsrc++;
164 		dest++;
165 		n--;
166 	}
167 	while(n >= 4) {
168 		*((u32 *)dest) = *((volatile u32 *)vsrc);
169 		eieio();
170 		vsrc += 4;
171 		dest += 4;
172 		n -= 4;
173 	}
174 	while(n) {
175 		*((u8 *)dest) = *((volatile u8 *)vsrc);
176 		eieio();
177 		vsrc++;
178 		dest++;
179 		n--;
180 	}
181 	__asm__ __volatile__ ("sync" : : : "memory");
182 }
183 EXPORT_SYMBOL(_memcpy_fromio);
184 
185 void _memcpy_toio(volatile void __iomem *dest, const void *src, unsigned long n)
186 {
187 	void *vdest = (void __force *) dest;
188 
189 	__asm__ __volatile__ ("sync" : : : "memory");
190 	while(n && (!IO_CHECK_ALIGN(vdest, 4) || !IO_CHECK_ALIGN(src, 4))) {
191 		*((volatile u8 *)vdest) = *((u8 *)src);
192 		src++;
193 		vdest++;
194 		n--;
195 	}
196 	while(n >= 4) {
197 		*((volatile u32 *)vdest) = *((volatile u32 *)src);
198 		src += 4;
199 		vdest += 4;
200 		n-=4;
201 	}
202 	while(n) {
203 		*((volatile u8 *)vdest) = *((u8 *)src);
204 		src++;
205 		vdest++;
206 		n--;
207 	}
208 	__asm__ __volatile__ ("sync" : : : "memory");
209 }
210 EXPORT_SYMBOL(_memcpy_toio);
211