xref: /linux/arch/sh/kernel/io.c (revision fd639726bf15fca8ee1a00dce8e0096d0ad9bd18)
1 /*
2  * arch/sh/kernel/io.c - Machine independent I/O functions.
3  *
4  * Copyright (C) 2000 - 2009  Stuart Menefy
5  * Copyright (C) 2005  Paul Mundt
6  *
7  * This file is subject to the terms and conditions of the GNU General Public
8  * License.  See the file "COPYING" in the main directory of this archive
9  * for more details.
10  */
11 #include <linux/module.h>
12 #include <linux/pci.h>
13 #include <asm/machvec.h>
14 #include <asm/io.h>
15 
16 /*
17  * Copy data from IO memory space to "real" memory space.
18  */
19 void memcpy_fromio(void *to, const volatile void __iomem *from, unsigned long count)
20 {
21 	/*
22 	 * Would it be worthwhile doing byte and long transfers first
23 	 * to try and get aligned?
24 	 */
25 #ifdef CONFIG_CPU_SH4
26 	if ((count >= 0x20) &&
27 	     (((u32)to & 0x1f) == 0) && (((u32)from & 0x3) == 0)) {
28 		int tmp2, tmp3, tmp4, tmp5, tmp6;
29 
30 		__asm__ __volatile__(
31 			"1:			\n\t"
32 			"mov.l	@%7+, r0	\n\t"
33 			"mov.l	@%7+, %2	\n\t"
34 			"movca.l r0, @%0	\n\t"
35 			"mov.l	@%7+, %3	\n\t"
36 			"mov.l	@%7+, %4	\n\t"
37 			"mov.l	@%7+, %5	\n\t"
38 			"mov.l	@%7+, %6	\n\t"
39 			"mov.l	@%7+, r7	\n\t"
40 			"mov.l	@%7+, r0	\n\t"
41 			"mov.l	%2, @(0x04,%0)	\n\t"
42 			"mov	#0x20, %2	\n\t"
43 			"mov.l	%3, @(0x08,%0)	\n\t"
44 			"sub	%2, %1		\n\t"
45 			"mov.l	%4, @(0x0c,%0)	\n\t"
46 			"cmp/hi	%1, %2		! T if 32 > count	\n\t"
47 			"mov.l	%5, @(0x10,%0)	\n\t"
48 			"mov.l	%6, @(0x14,%0)	\n\t"
49 			"mov.l	r7, @(0x18,%0)	\n\t"
50 			"mov.l	r0, @(0x1c,%0)	\n\t"
51 			"bf.s	1b		\n\t"
52 			" add	#0x20, %0	\n\t"
53 			: "=&r" (to), "=&r" (count),
54 			  "=&r" (tmp2), "=&r" (tmp3), "=&r" (tmp4),
55 			  "=&r" (tmp5), "=&r" (tmp6), "=&r" (from)
56 			: "7"(from), "0" (to), "1" (count)
57 			: "r0", "r7", "t", "memory");
58 	}
59 #endif
60 
61 	if ((((u32)to | (u32)from) & 0x3) == 0) {
62 		for (; count > 3; count -= 4) {
63 			*(u32 *)to = *(volatile u32 *)from;
64 			to += 4;
65 			from += 4;
66 		}
67 	}
68 
69 	for (; count > 0; count--) {
70 		*(u8 *)to = *(volatile u8 *)from;
71 		to++;
72 		from++;
73 	}
74 
75 	mb();
76 }
77 EXPORT_SYMBOL(memcpy_fromio);
78 
79 /*
80  * Copy data from "real" memory space to IO memory space.
81  */
82 void memcpy_toio(volatile void __iomem *to, const void *from, unsigned long count)
83 {
84 	if ((((u32)to | (u32)from) & 0x3) == 0) {
85 		for ( ; count > 3; count -= 4) {
86 			*(volatile u32 *)to = *(u32 *)from;
87 			to += 4;
88 			from += 4;
89 		}
90 	}
91 
92 	for (; count > 0; count--) {
93 		*(volatile u8 *)to = *(u8 *)from;
94 		to++;
95 		from++;
96 	}
97 
98 	mb();
99 }
100 EXPORT_SYMBOL(memcpy_toio);
101 
102 /*
103  * "memset" on IO memory space.
104  * This needs to be optimized.
105  */
106 void memset_io(volatile void __iomem *dst, int c, unsigned long count)
107 {
108         while (count) {
109                 count--;
110                 writeb(c, dst);
111                 dst++;
112         }
113 }
114 EXPORT_SYMBOL(memset_io);
115