1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * I/O string operations
4 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
5 * Copyright (C) 2006 IBM Corporation
6 *
7 * Largely rewritten by Cort Dougan (cort@cs.nmt.edu)
8 * and Paul Mackerras.
9 *
10 * Adapted for iSeries by Mike Corrigan (mikejc@us.ibm.com)
11 * PPC64 updates by Dave Engebretsen (engebret@us.ibm.com)
12 *
13 * Rewritten in C by Stephen Rothwell.
14 */
15#include <linux/kernel.h>
16#include <linux/types.h>
17#include <linux/compiler.h>
18#include <linux/export.h>
19
20#include <asm/io.h>
21#include <asm/firmware.h>
22#include <asm/bug.h>
23
24/* See definition in io.h */
25bool isa_io_special;
26
27void _insb(const volatile u8 __iomem *port, void *buf, long count)
28{
29 u8 *tbuf = buf;
30 u8 tmp;
31
32 if (unlikely(count <= 0))
33 return;
34
35 mb();
36 do {
37 tmp = *(const volatile u8 __force *)port;
38 eieio();
39 *tbuf++ = tmp;
40 } while (--count != 0);
41 data_barrier(tmp);
42}
43EXPORT_SYMBOL(_insb);
44
45void _outsb(volatile u8 __iomem *port, const void *buf, long count)
46{
47 const u8 *tbuf = buf;
48
49 if (unlikely(count <= 0))
50 return;
51
52 mb();
53 do {
54 *(volatile u8 __force *)port = *tbuf++;
55 } while (--count != 0);
56 mb();
57}
58EXPORT_SYMBOL(_outsb);
59
60void _insw(const volatile u16 __iomem *port, void *buf, long count)
61{
62 u16 *tbuf = buf;
63 u16 tmp;
64
65 if (unlikely(count <= 0))
66 return;
67
68 mb();
69 do {
70 tmp = *(const volatile u16 __force *)port;
71 eieio();
72 *tbuf++ = tmp;
73 } while (--count != 0);
74 data_barrier(tmp);
75}
76EXPORT_SYMBOL(_insw);
77
78void _outsw(volatile u16 __iomem *port, const void *buf, long count)
79{
80 const u16 *tbuf = buf;
81
82 if (unlikely(count <= 0))
83 return;
84
85 mb();
86 do {
87 *(volatile u16 __force *)port = *tbuf++;
88 } while (--count != 0);
89 mb();
90}
91EXPORT_SYMBOL(_outsw);
92
93void _insl(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
101 mb();
102 do {
103 tmp = *(const volatile u32 __force *)port;
104 eieio();
105 *tbuf++ = tmp;
106 } while (--count != 0);
107 data_barrier(tmp);
108}
109EXPORT_SYMBOL(_insl);
110
111void _outsl(volatile u32 __iomem *port, const void *buf, long count)
112{
113 const u32 *tbuf = buf;
114
115 if (unlikely(count <= 0))
116 return;
117
118 mb();
119 do {
120 *(volatile u32 __force *)port = *tbuf++;
121 } while (--count != 0);
122 mb();
123}
124EXPORT_SYMBOL(_outsl);
125
126#define IO_CHECK_ALIGN(v,a) ((((unsigned long)(v)) & ((a) - 1)) == 0)
127
128notrace void
129_memset_io(volatile void __iomem *addr, int c, unsigned long n)
130{
131 void *p = (void __force *)addr;
132 u32 lc = c;
133 lc |= lc << 8;
134 lc |= lc << 16;
135
136 mb();
137 while(n && !IO_CHECK_ALIGN(p, 4)) {
138 *((volatile u8 *)p) = c;
139 p++;
140 n--;
141 }
142 while(n >= 4) {
143 *((volatile u32 *)p) = lc;
144 p += 4;
145 n -= 4;
146 }
147 while(n) {
148 *((volatile u8 *)p) = c;
149 p++;
150 n--;
151 }
152 mb();
153}
154EXPORT_SYMBOL(_memset_io);
155
156void _memcpy_fromio(void *dest, const volatile void __iomem *src,
157 unsigned long n)
158{
159 void *vsrc = (void __force *) src;
160
161 mb();
162 while(n && (!IO_CHECK_ALIGN(vsrc, 4) || !IO_CHECK_ALIGN(dest, 4))) {
163 *((u8 *)dest) = *((volatile u8 *)vsrc);
164 eieio();
165 vsrc++;
166 dest++;
167 n--;
168 }
169 while(n >= 4) {
170 *((u32 *)dest) = *((volatile u32 *)vsrc);
171 eieio();
172 vsrc += 4;
173 dest += 4;
174 n -= 4;
175 }
176 while(n) {
177 *((u8 *)dest) = *((volatile u8 *)vsrc);
178 eieio();
179 vsrc++;
180 dest++;
181 n--;
182 }
183 mb();
184}
185EXPORT_SYMBOL(_memcpy_fromio);
186
187void _memcpy_toio(volatile void __iomem *dest, const void *src, unsigned long n)
188{
189 void *vdest = (void __force *) dest;
190
191 mb();
192 while(n && (!IO_CHECK_ALIGN(vdest, 4) || !IO_CHECK_ALIGN(src, 4))) {
193 *((volatile u8 *)vdest) = *((u8 *)src);
194 src++;
195 vdest++;
196 n--;
197 }
198 while(n >= 4) {
199 *((volatile u32 *)vdest) = *((volatile u32 *)src);
200 src += 4;
201 vdest += 4;
202 n-=4;
203 }
204 while(n) {
205 *((volatile u8 *)vdest) = *((u8 *)src);
206 src++;
207 vdest++;
208 n--;
209 }
210 mb();
211}
212EXPORT_SYMBOL(_memcpy_toio);
213

source code of linux/arch/powerpc/kernel/io.c