xref: /openbmc/linux/arch/powerpc/boot/io.h (revision fb574682)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _IO_H
3 #define _IO_H
4 
5 #include "types.h"
6 
7 /*
8  * Low-level I/O routines.
9  *
10  * Copied from <file:arch/powerpc/include/asm/io.h> (which has no copyright)
11  */
12 static inline int in_8(const volatile unsigned char *addr)
13 {
14 	int ret;
15 
16 	__asm__ __volatile__("lbz%U1%X1 %0,%1; twi 0,%0,0; isync"
17 			     : "=r" (ret) : "m" (*addr));
18 	return ret;
19 }
20 
21 static inline void out_8(volatile unsigned char *addr, int val)
22 {
23 	__asm__ __volatile__("stb%U0%X0 %1,%0; sync"
24 			     : "=m" (*addr) : "r" (val));
25 }
26 
27 static inline unsigned in_le16(const volatile u16 *addr)
28 {
29 	unsigned ret;
30 
31 	__asm__ __volatile__("lhbrx %0,0,%1; twi 0,%0,0; isync"
32 			     : "=r" (ret) : "r" (addr), "m" (*addr));
33 
34 	return ret;
35 }
36 
37 static inline unsigned in_be16(const volatile u16 *addr)
38 {
39 	unsigned ret;
40 
41 	__asm__ __volatile__("lhz%U1%X1 %0,%1; twi 0,%0,0; isync"
42 			     : "=r" (ret) : "m" (*addr));
43 	return ret;
44 }
45 
46 static inline void out_le16(volatile u16 *addr, int val)
47 {
48 	__asm__ __volatile__("sthbrx %1,0,%2; sync" : "=m" (*addr)
49 			     : "r" (val), "r" (addr));
50 }
51 
52 static inline void out_be16(volatile u16 *addr, int val)
53 {
54 	__asm__ __volatile__("sth%U0%X0 %1,%0; sync"
55 			     : "=m" (*addr) : "r" (val));
56 }
57 
58 static inline unsigned in_le32(const volatile unsigned *addr)
59 {
60 	unsigned ret;
61 
62 	__asm__ __volatile__("lwbrx %0,0,%1; twi 0,%0,0; isync"
63 			     : "=r" (ret) : "r" (addr), "m" (*addr));
64 	return ret;
65 }
66 
67 static inline unsigned in_be32(const volatile unsigned *addr)
68 {
69 	unsigned ret;
70 
71 	__asm__ __volatile__("lwz%U1%X1 %0,%1; twi 0,%0,0; isync"
72 			     : "=r" (ret) : "m" (*addr));
73 	return ret;
74 }
75 
76 static inline void out_le32(volatile unsigned *addr, int val)
77 {
78 	__asm__ __volatile__("stwbrx %1,0,%2; sync" : "=m" (*addr)
79 			     : "r" (val), "r" (addr));
80 }
81 
82 static inline void out_be32(volatile unsigned *addr, int val)
83 {
84 	__asm__ __volatile__("stw%U0%X0 %1,%0; sync"
85 			     : "=m" (*addr) : "r" (val));
86 }
87 
88 static inline void sync(void)
89 {
90 	asm volatile("sync" : : : "memory");
91 }
92 
93 static inline void eieio(void)
94 {
95 	asm volatile("eieio" : : : "memory");
96 }
97 
98 static inline void barrier(void)
99 {
100 	asm volatile("" : : : "memory");
101 }
102 
103 #endif /* _IO_H */
104