1 /*
2 * Based on arch/arm/kernel/io.c
3 *
4 * Copyright (C) 2012 ARM Ltd.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program. If not, see <http://www.gnu.org/licenses/>.
17 */
18
19 #include <linux/export.h>
20 #include <linux/types.h>
21 #include <linux/io.h>
22
23 /*
24 * Copy data from IO memory space to "real" memory space.
25 */
__memcpy_fromio(void * to,const volatile void __iomem * from,size_t count)26 void __memcpy_fromio(void *to, const volatile void __iomem *from, size_t count)
27 {
28 while (count && !IS_ALIGNED((unsigned long)from, 8)) {
29 *(u8 *)to = __raw_readb(from);
30 from++;
31 to++;
32 count--;
33 }
34
35 while (count >= 8) {
36 *(u64 *)to = __raw_readq(from);
37 from += 8;
38 to += 8;
39 count -= 8;
40 }
41
42 while (count) {
43 *(u8 *)to = __raw_readb(from);
44 from++;
45 to++;
46 count--;
47 }
48 }
49 EXPORT_SYMBOL(__memcpy_fromio);
50
51 /*
52 * Copy data from "real" memory space to IO memory space.
53 */
__memcpy_toio(volatile void __iomem * to,const void * from,size_t count)54 void __memcpy_toio(volatile void __iomem *to, const void *from, size_t count)
55 {
56 while (count && !IS_ALIGNED((unsigned long)to, 8)) {
57 __raw_writeb(*(u8 *)from, to);
58 from++;
59 to++;
60 count--;
61 }
62
63 while (count >= 8) {
64 __raw_writeq(*(u64 *)from, to);
65 from += 8;
66 to += 8;
67 count -= 8;
68 }
69
70 while (count) {
71 __raw_writeb(*(u8 *)from, to);
72 from++;
73 to++;
74 count--;
75 }
76 }
77 EXPORT_SYMBOL(__memcpy_toio);
78
79 /*
80 * "memset" on IO memory space.
81 */
__memset_io(volatile void __iomem * dst,int c,size_t count)82 void __memset_io(volatile void __iomem *dst, int c, size_t count)
83 {
84 u64 qc = (u8)c;
85
86 qc |= qc << 8;
87 qc |= qc << 16;
88 qc |= qc << 32;
89
90 while (count && !IS_ALIGNED((unsigned long)dst, 8)) {
91 __raw_writeb(c, dst);
92 dst++;
93 count--;
94 }
95
96 while (count >= 8) {
97 __raw_writeq(qc, dst);
98 dst += 8;
99 count -= 8;
100 }
101
102 while (count) {
103 __raw_writeb(c, dst);
104 dst++;
105 count--;
106 }
107 }
108 EXPORT_SYMBOL(__memset_io);
109