summaryrefslogtreecommitdiff
path: root/include/asm-i386/io.h
blob: d8c503ccb32fd227367636f85fe049b8f6245dc1 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
#ifndef _ASM_IO_H
#define _ASM_IO_H

#include <linux/config.h>

/*
 * This file contains the definitions for the x86 IO instructions
 * inb/inw/inl/outb/outw/outl and the "string versions" of the same
 * (insb/insw/insl/outsb/outsw/outsl). You can also use "pausing"
 * versions of the single-IO instructions (inb_p/inw_p/..).
 *
 * This file is not meant to be obfuscating: it's just complicated
 * to (a) handle it all in a way that makes gcc able to optimize it
 * as well as possible and (b) trying to avoid writing the same thing
 * over and over again with slight variations and possibly making a
 * mistake somewhere.
 */

/*
 * Thanks to James van Artsdalen for a better timing-fix than
 * the two short jumps: using outb's to a nonexistent port seems
 * to guarantee better timings even on fast machines.
 *
 * On the other hand, I'd like to be sure of a non-existent port:
 * I feel a bit unsafe about using 0x80 (should be safe, though)
 *
 *		Linus
 */

 /*
  *  Bit simplified and optimized by Jan Hubicka
  *  Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999.
  *
  *  isa_memset_io, isa_memcpy_fromio, isa_memcpy_toio added,
  *  isa_read[wl] and isa_write[wl] fixed
  *  - Arnaldo Carvalho de Melo <acme@conectiva.com.br>
  */

#define IO_SPACE_LIMIT 0xffff


#ifdef __KERNEL__


/*
 * readX/writeX() are used to access memory mapped devices. On some
 * architectures the memory mapped IO stuff needs to be accessed
 * differently. On the x86 architecture, we just read/write the
 * memory location directly.
 */

#define readb(addr) (*(volatile unsigned char *) (addr))
#define readw(addr) (*(volatile unsigned short *) (addr))
#define readl(addr) (*(volatile unsigned int *) (addr))
#define __raw_readb readb
#define __raw_readw readw
#define __raw_readl readl

#define writeb(b,addr) (*(volatile unsigned char *) (addr) = (b))
#define writew(b,addr) (*(volatile unsigned short *) (addr) = (b))
#define writel(b,addr) (*(volatile unsigned int *) (addr) = (b))
#define __raw_writeb writeb
#define __raw_writew writew
#define __raw_writel writel

#define memset_io(a,b,c)	memset((a),(b),(c))
#define memcpy_fromio(a,b,c)	memcpy((a),(b),(c))
#define memcpy_toio(a,b,c)	memcpy((a),(b),(c))

/*
 * ISA space is 'always mapped' on a typical x86 system, no need to
 * explicitly ioremap() it. The fact that the ISA IO space is mapped
 * to PAGE_OFFSET is pure coincidence - it does not mean ISA values
 * are physical addresses. The following constant pointer can be
 * used as the IO-area pointer (it can be iounmapped as well, so the
 * analogy with PCI is quite large):
 */
#define isa_readb(a) readb((a))
#define isa_readw(a) readw((a))
#define isa_readl(a) readl((a))
#define isa_writeb(b,a) writeb(b,(a))
#define isa_writew(w,a) writew(w,(a))
#define isa_writel(l,a) writel(l,(a))
#define isa_memset_io(a,b,c)		memset_io((a),(b),(c))
#define isa_memcpy_fromio(a,b,c)	memcpy_fromio((a),(b),(c))
#define isa_memcpy_toio(a,b,c)		memcpy_toio((a),(b),(c))


 
static inline int check_signature(unsigned long io_addr,
	const unsigned char *signature, int length)
{
	int retval = 0;
	do {
		if (readb(io_addr) != *signature)
			goto out;
		io_addr++;
		signature++;
		length--;
	} while (length);
	retval = 1;
out:
	return retval;
}

/**
 *	isa_check_signature		-	find BIOS signatures
 *	@io_addr: mmio address to check 
 *	@signature:  signature block
 *	@length: length of signature
 *
 *	Perform a signature comparison with the ISA mmio address io_addr.
 *	Returns 1 on a match.
 *
 *	This function is deprecated. New drivers should use ioremap and
 *	check_signature.
 */
 

static inline int isa_check_signature(unsigned long io_addr,
	const unsigned char *signature, int length)
{
	int retval = 0;
	do {
		if (isa_readb(io_addr) != *signature)
			goto out;
		io_addr++;
		signature++;
		length--;
	} while (length);
	retval = 1;
out:
	return retval;
}

#endif /* __KERNEL__ */

#ifdef SLOW_IO_BY_JUMPING
#define __SLOW_DOWN_IO "\njmp 1f\n1:\tjmp 1f\n1:"
#else
#define __SLOW_DOWN_IO "\noutb %%al,$0x80"
#endif

#ifdef REALLY_SLOW_IO
#define __FULL_SLOW_DOWN_IO __SLOW_DOWN_IO __SLOW_DOWN_IO __SLOW_DOWN_IO __SLOW_DOWN_IO
#else
#define __FULL_SLOW_DOWN_IO __SLOW_DOWN_IO
#endif


/*
 * Talk about misusing macros..
 */
#define __OUT1(s,x) \
static inline void out##s(unsigned x value, unsigned short port) {

#define __OUT2(s,s1,s2) \
__asm__ __volatile__ ("out" #s " %" s1 "0,%" s2 "1"


#define __OUT(s,s1,x) \
__OUT1(s,x) __OUT2(s,s1,"w") : : "a" (value), "Nd" (port)); } \
__OUT1(s##_p,x) __OUT2(s,s1,"w") __FULL_SLOW_DOWN_IO : : "a" (value), "Nd" (port));} 

#define __IN1(s) \
static inline RETURN_TYPE in##s(unsigned short port) { RETURN_TYPE _v;

#define __IN2(s,s1,s2) \
__asm__ __volatile__ ("in" #s " %" s2 "1,%" s1 "0"

#define __IN(s,s1,i...) \
__IN1(s) __IN2(s,s1,"w") : "=a" (_v) : "Nd" (port) ,##i ); return _v; } \
__IN1(s##_p) __IN2(s,s1,"w") __FULL_SLOW_DOWN_IO : "=a" (_v) : "Nd" (port) ,##i ); return _v; } 

#define __INS(s) \
static inline void ins##s(unsigned short port, void * addr, unsigned long count) \
{ __asm__ __volatile__ ("rep ; ins" #s \
: "=D" (addr), "=c" (count) : "d" (port),"0" (addr),"1" (count)); }

#define __OUTS(s) \
static inline void outs##s(unsigned short port, const void * addr, unsigned long count) \
{ __asm__ __volatile__ ("rep ; outs" #s \
: "=S" (addr), "=c" (count) : "d" (port),"0" (addr),"1" (count)); }

#define RETURN_TYPE unsigned char
__IN(b,"")
#undef RETURN_TYPE
#define RETURN_TYPE unsigned short
__IN(w,"")
#undef RETURN_TYPE
#define RETURN_TYPE unsigned int
__IN(l,"")
#undef RETURN_TYPE

__OUT(b,"b",char)
__OUT(w,"w",short)
__OUT(l,,int)

__INS(b)
__INS(w)
__INS(l)

__OUTS(b)
__OUTS(w)
__OUTS(l)

#endif