efivars: Refactor sanity checking code into separate function
[linux/fpc-iii.git] / arch / powerpc / kernel / io.c
blob2a2b4aeab80fd83ca276bcccfef6387f3324d565
1 /*
2 * I/O string operations
3 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
4 * Copyright (C) 2006 IBM Corporation
6 * Largely rewritten by Cort Dougan (cort@cs.nmt.edu)
7 * and Paul Mackerras.
9 * Adapted for iSeries by Mike Corrigan (mikejc@us.ibm.com)
10 * PPC64 updates by Dave Engebretsen (engebret@us.ibm.com)
12 * Rewritten in C by Stephen Rothwell.
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.
19 #include <linux/kernel.h>
20 #include <linux/types.h>
21 #include <linux/compiler.h>
22 #include <linux/export.h>
24 #include <asm/io.h>
25 #include <asm/firmware.h>
26 #include <asm/bug.h>
28 /* See definition in io.h */
29 bool isa_io_special;
31 void _insb(const volatile u8 __iomem *port, void *buf, long count)
33 u8 *tbuf = buf;
34 u8 tmp;
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));
46 EXPORT_SYMBOL(_insb);
48 void _outsb(volatile u8 __iomem *port, const void *buf, long count)
50 const u8 *tbuf = buf;
52 if (unlikely(count <= 0))
53 return;
54 asm volatile("sync");
55 do {
56 *port = *tbuf++;
57 } while (--count != 0);
58 asm volatile("sync");
60 EXPORT_SYMBOL(_outsb);
62 void _insw_ns(const volatile u16 __iomem *port, void *buf, long count)
64 u16 *tbuf = buf;
65 u16 tmp;
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));
77 EXPORT_SYMBOL(_insw_ns);
79 void _outsw_ns(volatile u16 __iomem *port, const void *buf, long count)
81 const u16 *tbuf = buf;
83 if (unlikely(count <= 0))
84 return;
85 asm volatile("sync");
86 do {
87 *port = *tbuf++;
88 } while (--count != 0);
89 asm volatile("sync");
91 EXPORT_SYMBOL(_outsw_ns);
93 void _insl_ns(const volatile u32 __iomem *port, void *buf, long count)
95 u32 *tbuf = buf;
96 u32 tmp;
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));
108 EXPORT_SYMBOL(_insl_ns);
110 void _outsl_ns(volatile u32 __iomem *port, const void *buf, long count)
112 const u32 *tbuf = buf;
114 if (unlikely(count <= 0))
115 return;
116 asm volatile("sync");
117 do {
118 *port = *tbuf++;
119 } while (--count != 0);
120 asm volatile("sync");
122 EXPORT_SYMBOL(_outsl_ns);
124 #define IO_CHECK_ALIGN(v,a) ((((unsigned long)(v)) & ((a) - 1)) == 0)
126 notrace void
127 _memset_io(volatile void __iomem *addr, int c, unsigned long n)
129 void *p = (void __force *)addr;
130 u32 lc = c;
131 lc |= lc << 8;
132 lc |= lc << 16;
134 __asm__ __volatile__ ("sync" : : : "memory");
135 while(n && !IO_CHECK_ALIGN(p, 4)) {
136 *((volatile u8 *)p) = c;
137 p++;
138 n--;
140 while(n >= 4) {
141 *((volatile u32 *)p) = lc;
142 p += 4;
143 n -= 4;
145 while(n) {
146 *((volatile u8 *)p) = c;
147 p++;
148 n--;
150 __asm__ __volatile__ ("sync" : : : "memory");
152 EXPORT_SYMBOL(_memset_io);
154 void _memcpy_fromio(void *dest, const volatile void __iomem *src,
155 unsigned long n)
157 void *vsrc = (void __force *) src;
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--;
167 while(n >= 4) {
168 *((u32 *)dest) = *((volatile u32 *)vsrc);
169 eieio();
170 vsrc += 4;
171 dest += 4;
172 n -= 4;
174 while(n) {
175 *((u8 *)dest) = *((volatile u8 *)vsrc);
176 eieio();
177 vsrc++;
178 dest++;
179 n--;
181 __asm__ __volatile__ ("sync" : : : "memory");
183 EXPORT_SYMBOL(_memcpy_fromio);
185 void _memcpy_toio(volatile void __iomem *dest, const void *src, unsigned long n)
187 void *vdest = (void __force *) dest;
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--;
196 while(n >= 4) {
197 *((volatile u32 *)vdest) = *((volatile u32 *)src);
198 src += 4;
199 vdest += 4;
200 n-=4;
202 while(n) {
203 *((volatile u8 *)vdest) = *((u8 *)src);
204 src++;
205 vdest++;
206 n--;
208 __asm__ __volatile__ ("sync" : : : "memory");
210 EXPORT_SYMBOL(_memcpy_toio);