xref: /linux/arch/powerpc/kernel/io.c (revision 3d0fe49454652117522f60bfbefb978ba0e5300b)
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 */
25 bool isa_io_special;
26 
27 void _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 	asm volatile("sync");
35 	do {
36 		tmp = *(const volatile u8 __force *)port;
37 		eieio();
38 		*tbuf++ = tmp;
39 	} while (--count != 0);
40 	asm volatile("twi 0,%0,0; isync" : : "r" (tmp));
41 }
42 EXPORT_SYMBOL(_insb);
43 
44 void _outsb(volatile u8 __iomem *port, const void *buf, long count)
45 {
46 	const u8 *tbuf = buf;
47 
48 	if (unlikely(count <= 0))
49 		return;
50 	asm volatile("sync");
51 	do {
52 		*(volatile u8 __force *)port = *tbuf++;
53 	} while (--count != 0);
54 	asm volatile("sync");
55 }
56 EXPORT_SYMBOL(_outsb);
57 
58 void _insw_ns(const volatile u16 __iomem *port, void *buf, long count)
59 {
60 	u16 *tbuf = buf;
61 	u16 tmp;
62 
63 	if (unlikely(count <= 0))
64 		return;
65 	asm volatile("sync");
66 	do {
67 		tmp = *(const volatile u16 __force *)port;
68 		eieio();
69 		*tbuf++ = tmp;
70 	} while (--count != 0);
71 	asm volatile("twi 0,%0,0; isync" : : "r" (tmp));
72 }
73 EXPORT_SYMBOL(_insw_ns);
74 
75 void _outsw_ns(volatile u16 __iomem *port, const void *buf, long count)
76 {
77 	const u16 *tbuf = buf;
78 
79 	if (unlikely(count <= 0))
80 		return;
81 	asm volatile("sync");
82 	do {
83 		*(volatile u16 __force *)port = *tbuf++;
84 	} while (--count != 0);
85 	asm volatile("sync");
86 }
87 EXPORT_SYMBOL(_outsw_ns);
88 
89 void _insl_ns(const volatile u32 __iomem *port, void *buf, long count)
90 {
91 	u32 *tbuf = buf;
92 	u32 tmp;
93 
94 	if (unlikely(count <= 0))
95 		return;
96 	asm volatile("sync");
97 	do {
98 		tmp = *(const volatile u32 __force *)port;
99 		eieio();
100 		*tbuf++ = tmp;
101 	} while (--count != 0);
102 	asm volatile("twi 0,%0,0; isync" : : "r" (tmp));
103 }
104 EXPORT_SYMBOL(_insl_ns);
105 
106 void _outsl_ns(volatile u32 __iomem *port, const void *buf, long count)
107 {
108 	const u32 *tbuf = buf;
109 
110 	if (unlikely(count <= 0))
111 		return;
112 	asm volatile("sync");
113 	do {
114 		*(volatile u32 __force *)port = *tbuf++;
115 	} while (--count != 0);
116 	asm volatile("sync");
117 }
118 EXPORT_SYMBOL(_outsl_ns);
119 
120 #define IO_CHECK_ALIGN(v,a) ((((unsigned long)(v)) & ((a) - 1)) == 0)
121 
122 notrace void
123 _memset_io(volatile void __iomem *addr, int c, unsigned long n)
124 {
125 	void *p = (void __force *)addr;
126 	u32 lc = c;
127 	lc |= lc << 8;
128 	lc |= lc << 16;
129 
130 	__asm__ __volatile__ ("sync" : : : "memory");
131 	while(n && !IO_CHECK_ALIGN(p, 4)) {
132 		*((volatile u8 *)p) = c;
133 		p++;
134 		n--;
135 	}
136 	while(n >= 4) {
137 		*((volatile u32 *)p) = lc;
138 		p += 4;
139 		n -= 4;
140 	}
141 	while(n) {
142 		*((volatile u8 *)p) = c;
143 		p++;
144 		n--;
145 	}
146 	__asm__ __volatile__ ("sync" : : : "memory");
147 }
148 EXPORT_SYMBOL(_memset_io);
149 
150 void _memcpy_fromio(void *dest, const volatile void __iomem *src,
151 		    unsigned long n)
152 {
153 	void *vsrc = (void __force *) src;
154 
155 	__asm__ __volatile__ ("sync" : : : "memory");
156 	while(n && (!IO_CHECK_ALIGN(vsrc, 4) || !IO_CHECK_ALIGN(dest, 4))) {
157 		*((u8 *)dest) = *((volatile u8 *)vsrc);
158 		eieio();
159 		vsrc++;
160 		dest++;
161 		n--;
162 	}
163 	while(n >= 4) {
164 		*((u32 *)dest) = *((volatile u32 *)vsrc);
165 		eieio();
166 		vsrc += 4;
167 		dest += 4;
168 		n -= 4;
169 	}
170 	while(n) {
171 		*((u8 *)dest) = *((volatile u8 *)vsrc);
172 		eieio();
173 		vsrc++;
174 		dest++;
175 		n--;
176 	}
177 	__asm__ __volatile__ ("sync" : : : "memory");
178 }
179 EXPORT_SYMBOL(_memcpy_fromio);
180 
181 void _memcpy_toio(volatile void __iomem *dest, const void *src, unsigned long n)
182 {
183 	void *vdest = (void __force *) dest;
184 
185 	__asm__ __volatile__ ("sync" : : : "memory");
186 	while(n && (!IO_CHECK_ALIGN(vdest, 4) || !IO_CHECK_ALIGN(src, 4))) {
187 		*((volatile u8 *)vdest) = *((u8 *)src);
188 		src++;
189 		vdest++;
190 		n--;
191 	}
192 	while(n >= 4) {
193 		*((volatile u32 *)vdest) = *((volatile u32 *)src);
194 		src += 4;
195 		vdest += 4;
196 		n-=4;
197 	}
198 	while(n) {
199 		*((volatile u8 *)vdest) = *((u8 *)src);
200 		src++;
201 		vdest++;
202 		n--;
203 	}
204 	__asm__ __volatile__ ("sync" : : : "memory");
205 }
206 EXPORT_SYMBOL(_memcpy_toio);
207