xref: /openbmc/linux/arch/sh/kernel/io.c (revision e15a5365)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * arch/sh/kernel/io.c - Machine independent I/O functions.
4  *
5  * Copyright (C) 2000 - 2009  Stuart Menefy
6  * Copyright (C) 2005  Paul Mundt
7  */
8 #include <linux/module.h>
9 #include <linux/pci.h>
10 #include <asm/machvec.h>
11 #include <asm/io.h>
12 
13 /*
14  * Copy data from IO memory space to "real" memory space.
15  */
16 void memcpy_fromio(void *to, const volatile void __iomem *from, unsigned long count)
17 {
18 	/*
19 	 * Would it be worthwhile doing byte and long transfers first
20 	 * to try and get aligned?
21 	 */
22 #ifdef CONFIG_CPU_SH4
23 	if ((count >= 0x20) &&
24 	     (((u32)to & 0x1f) == 0) && (((u32)from & 0x3) == 0)) {
25 		int tmp2, tmp3, tmp4, tmp5, tmp6;
26 
27 		__asm__ __volatile__(
28 			"1:			\n\t"
29 			"mov.l	@%7+, r0	\n\t"
30 			"mov.l	@%7+, %2	\n\t"
31 			"movca.l r0, @%0	\n\t"
32 			"mov.l	@%7+, %3	\n\t"
33 			"mov.l	@%7+, %4	\n\t"
34 			"mov.l	@%7+, %5	\n\t"
35 			"mov.l	@%7+, %6	\n\t"
36 			"mov.l	@%7+, r7	\n\t"
37 			"mov.l	@%7+, r0	\n\t"
38 			"mov.l	%2, @(0x04,%0)	\n\t"
39 			"mov	#0x20, %2	\n\t"
40 			"mov.l	%3, @(0x08,%0)	\n\t"
41 			"sub	%2, %1		\n\t"
42 			"mov.l	%4, @(0x0c,%0)	\n\t"
43 			"cmp/hi	%1, %2		! T if 32 > count	\n\t"
44 			"mov.l	%5, @(0x10,%0)	\n\t"
45 			"mov.l	%6, @(0x14,%0)	\n\t"
46 			"mov.l	r7, @(0x18,%0)	\n\t"
47 			"mov.l	r0, @(0x1c,%0)	\n\t"
48 			"bf.s	1b		\n\t"
49 			" add	#0x20, %0	\n\t"
50 			: "=&r" (to), "=&r" (count),
51 			  "=&r" (tmp2), "=&r" (tmp3), "=&r" (tmp4),
52 			  "=&r" (tmp5), "=&r" (tmp6), "=&r" (from)
53 			: "7"(from), "0" (to), "1" (count)
54 			: "r0", "r7", "t", "memory");
55 	}
56 #endif
57 
58 	if ((((u32)to | (u32)from) & 0x3) == 0) {
59 		for (; count > 3; count -= 4) {
60 			*(u32 *)to = *(volatile u32 *)from;
61 			to += 4;
62 			from += 4;
63 		}
64 	}
65 
66 	for (; count > 0; count--) {
67 		*(u8 *)to = *(volatile u8 *)from;
68 		to++;
69 		from++;
70 	}
71 
72 	mb();
73 }
74 EXPORT_SYMBOL(memcpy_fromio);
75 
76 /*
77  * Copy data from "real" memory space to IO memory space.
78  */
79 void memcpy_toio(volatile void __iomem *to, const void *from, unsigned long count)
80 {
81 	if ((((u32)to | (u32)from) & 0x3) == 0) {
82 		for ( ; count > 3; count -= 4) {
83 			*(volatile u32 *)to = *(u32 *)from;
84 			to += 4;
85 			from += 4;
86 		}
87 	}
88 
89 	for (; count > 0; count--) {
90 		*(volatile u8 *)to = *(u8 *)from;
91 		to++;
92 		from++;
93 	}
94 
95 	mb();
96 }
97 EXPORT_SYMBOL(memcpy_toio);
98 
99 /*
100  * "memset" on IO memory space.
101  * This needs to be optimized.
102  */
103 void memset_io(volatile void __iomem *dst, int c, unsigned long count)
104 {
105         while (count) {
106                 count--;
107                 writeb(c, dst);
108                 dst++;
109         }
110 }
111 EXPORT_SYMBOL(memset_io);
112