File: /usr/src/linux/include/asm-i386/io.h
1 #ifndef _ASM_IO_H
2 #define _ASM_IO_H
3
4 #include <linux/config.h>
5
6 /*
7 * This file contains the definitions for the x86 IO instructions
8 * inb/inw/inl/outb/outw/outl and the "string versions" of the same
9 * (insb/insw/insl/outsb/outsw/outsl). You can also use "pausing"
10 * versions of the single-IO instructions (inb_p/inw_p/..).
11 *
12 * This file is not meant to be obfuscating: it's just complicated
13 * to (a) handle it all in a way that makes gcc able to optimize it
14 * as well as possible and (b) trying to avoid writing the same thing
15 * over and over again with slight variations and possibly making a
16 * mistake somewhere.
17 */
18
19 /*
20 * Thanks to James van Artsdalen for a better timing-fix than
21 * the two short jumps: using outb's to a nonexistent port seems
22 * to guarantee better timings even on fast machines.
23 *
24 * On the other hand, I'd like to be sure of a non-existent port:
25 * I feel a bit unsafe about using 0x80 (should be safe, though)
26 *
27 * Linus
28 */
29
30 /*
31 * Bit simplified and optimized by Jan Hubicka
32 * Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999.
33 *
34 * isa_memset_io, isa_memcpy_fromio, isa_memcpy_toio added,
35 * isa_read[wl] and isa_write[wl] fixed
36 * - Arnaldo Carvalho de Melo <acme@conectiva.com.br>
37 */
38
39 #ifdef SLOW_IO_BY_JUMPING
40 #define __SLOW_DOWN_IO "\njmp 1f\n1:\tjmp 1f\n1:"
41 #else
42 #define __SLOW_DOWN_IO "\noutb %%al,$0x80"
43 #endif
44
45 #ifdef REALLY_SLOW_IO
46 #define __FULL_SLOW_DOWN_IO __SLOW_DOWN_IO __SLOW_DOWN_IO __SLOW_DOWN_IO __SLOW_DOWN_IO
47 #else
48 #define __FULL_SLOW_DOWN_IO __SLOW_DOWN_IO
49 #endif
50
51 /*
52 * Talk about misusing macros..
53 */
54 #define __OUT1(s,x) \
55 static inline void out##s(unsigned x value, unsigned short port) {
56
57 #define __OUT2(s,s1,s2) \
58 __asm__ __volatile__ ("out" #s " %" s1 "0,%" s2 "1"
59
60 #define __OUT(s,s1,x) \
61 __OUT1(s,x) __OUT2(s,s1,"w") : : "a" (value), "Nd" (port)); } \
62 __OUT1(s##_p,x) __OUT2(s,s1,"w") __FULL_SLOW_DOWN_IO : : "a" (value), "Nd" (port));} \
63
64 #define __IN1(s) \
65 static inline RETURN_TYPE in##s(unsigned short port) { RETURN_TYPE _v;
66
67 #define __IN2(s,s1,s2) \
68 __asm__ __volatile__ ("in" #s " %" s2 "1,%" s1 "0"
69
70 #define __IN(s,s1,i...) \
71 __IN1(s) __IN2(s,s1,"w") : "=a" (_v) : "Nd" (port) ,##i ); return _v; } \
72 __IN1(s##_p) __IN2(s,s1,"w") __FULL_SLOW_DOWN_IO : "=a" (_v) : "Nd" (port) ,##i ); return _v; } \
73
74 #define __INS(s) \
75 static inline void ins##s(unsigned short port, void * addr, unsigned long count) \
76 { __asm__ __volatile__ ("rep ; ins" #s \
77 : "=D" (addr), "=c" (count) : "d" (port),"0" (addr),"1" (count)); }
78
79 #define __OUTS(s) \
80 static inline void outs##s(unsigned short port, const void * addr, unsigned long count) \
81 { __asm__ __volatile__ ("rep ; outs" #s \
82 : "=S" (addr), "=c" (count) : "d" (port),"0" (addr),"1" (count)); }
83
84 #define RETURN_TYPE unsigned char
85 __IN(b,"")
86 #undef RETURN_TYPE
87 #define RETURN_TYPE unsigned short
88 __IN(w,"")
89 #undef RETURN_TYPE
90 #define RETURN_TYPE unsigned int
91 __IN(l,"")
92 #undef RETURN_TYPE
93
94 __OUT(b,"b",char)
95 __OUT(w,"w",short)
96 __OUT(l,,int)
97
98 __INS(b)
99 __INS(w)
100 __INS(l)
101
102 __OUTS(b)
103 __OUTS(w)
104 __OUTS(l)
105
106 #define IO_SPACE_LIMIT 0xffff
107
108 #ifdef __KERNEL__
109
110 #include <linux/vmalloc.h>
111
112 /*
113 * Temporary debugging check to catch old code using
114 * unmapped ISA addresses. Will be removed in 2.4.
115 */
116 #if CONFIG_DEBUG_IOVIRT
117 extern void *__io_virt_debug(unsigned long x, const char *file, int line);
118 extern unsigned long __io_phys_debug(unsigned long x, const char *file, int line);
119 #define __io_virt(x) __io_virt_debug((unsigned long)(x), __FILE__, __LINE__)
120 //#define __io_phys(x) __io_phys_debug((unsigned long)(x), __FILE__, __LINE__)
121 #else
122 #define __io_virt(x) ((void *)(x))
123 //#define __io_phys(x) __pa(x)
124 #endif
125
126 /*
127 * Change virtual addresses to physical addresses and vv.
128 * These are pretty trivial
129 */
130 static inline unsigned long virt_to_phys(volatile void * address)
131 {
132 return __pa(address);
133 }
134
135 static inline void * phys_to_virt(unsigned long address)
136 {
137 return __va(address);
138 }
139
140 /*
141 * Change "struct page" to physical address.
142 */
143 #define page_to_phys(page) ((page - mem_map) << PAGE_SHIFT)
144
145 extern void * __ioremap(unsigned long offset, unsigned long size, unsigned long flags);
146
147 static inline void * ioremap (unsigned long offset, unsigned long size)
148 {
149 return __ioremap(offset, size, 0);
150 }
151
152 /*
153 * This one maps high address device memory and turns off caching for that area.
154 * it's useful if some control registers are in such an area and write combining
155 * or read caching is not desirable:
156 */
157 static inline void * ioremap_nocache (unsigned long offset, unsigned long size)
158 {
159 return __ioremap(offset, size, _PAGE_PCD);
160 }
161
162 extern void iounmap(void *addr);
163
164 /*
165 * IO bus memory addresses are also 1:1 with the physical address
166 */
167 #define virt_to_bus virt_to_phys
168 #define bus_to_virt phys_to_virt
169 #define page_to_bus page_to_phys
170
171 /*
172 * readX/writeX() are used to access memory mapped devices. On some
173 * architectures the memory mapped IO stuff needs to be accessed
174 * differently. On the x86 architecture, we just read/write the
175 * memory location directly.
176 */
177
178 #define readb(addr) (*(volatile unsigned char *) __io_virt(addr))
179 #define readw(addr) (*(volatile unsigned short *) __io_virt(addr))
180 #define readl(addr) (*(volatile unsigned int *) __io_virt(addr))
181 #define __raw_readb readb
182 #define __raw_readw readw
183 #define __raw_readl readl
184
185 #define writeb(b,addr) (*(volatile unsigned char *) __io_virt(addr) = (b))
186 #define writew(b,addr) (*(volatile unsigned short *) __io_virt(addr) = (b))
187 #define writel(b,addr) (*(volatile unsigned int *) __io_virt(addr) = (b))
188 #define __raw_writeb writeb
189 #define __raw_writew writew
190 #define __raw_writel writel
191
192 #define memset_io(a,b,c) memset(__io_virt(a),(b),(c))
193 #define memcpy_fromio(a,b,c) memcpy((a),__io_virt(b),(c))
194 #define memcpy_toio(a,b,c) memcpy(__io_virt(a),(b),(c))
195
196 /*
197 * ISA space is 'always mapped' on a typical x86 system, no need to
198 * explicitly ioremap() it. The fact that the ISA IO space is mapped
199 * to PAGE_OFFSET is pure coincidence - it does not mean ISA values
200 * are physical addresses. The following constant pointer can be
201 * used as the IO-area pointer (it can be iounmapped as well, so the
202 * analogy with PCI is quite large):
203 */
204 #define __ISA_IO_base ((char *)(PAGE_OFFSET))
205
206 #define isa_readb(a) readb(__ISA_IO_base + (a))
207 #define isa_readw(a) readw(__ISA_IO_base + (a))
208 #define isa_readl(a) readl(__ISA_IO_base + (a))
209 #define isa_writeb(b,a) writeb(b,__ISA_IO_base + (a))
210 #define isa_writew(w,a) writew(w,__ISA_IO_base + (a))
211 #define isa_writel(l,a) writel(l,__ISA_IO_base + (a))
212 #define isa_memset_io(a,b,c) memset_io(__ISA_IO_base + (a),(b),(c))
213 #define isa_memcpy_fromio(a,b,c) memcpy_fromio((a),__ISA_IO_base + (b),(c))
214 #define isa_memcpy_toio(a,b,c) memcpy_toio(__ISA_IO_base + (a),(b),(c))
215
216
217 /*
218 * Again, i386 does not require mem IO specific function.
219 */
220
221 #define eth_io_copy_and_sum(a,b,c,d) eth_copy_and_sum((a),__io_virt(b),(c),(d))
222 #define isa_eth_io_copy_and_sum(a,b,c,d) eth_copy_and_sum((a),__io_virt(__ISA_IO_base + (b)),(c),(d))
223
224 static inline int check_signature(unsigned long io_addr,
225 const unsigned char *signature, int length)
226 {
227 int retval = 0;
228 do {
229 if (readb(io_addr) != *signature)
230 goto out;
231 io_addr++;
232 signature++;
233 length--;
234 } while (length);
235 retval = 1;
236 out:
237 return retval;
238 }
239
240 static inline int isa_check_signature(unsigned long io_addr,
241 const unsigned char *signature, int length)
242 {
243 int retval = 0;
244 do {
245 if (isa_readb(io_addr) != *signature)
246 goto out;
247 io_addr++;
248 signature++;
249 length--;
250 } while (length);
251 retval = 1;
252 out:
253 return retval;
254 }
255
256 /* Nothing to do */
257
258 #define dma_cache_inv(_start,_size) do { } while (0)
259 #define dma_cache_wback(_start,_size) do { } while (0)
260 #define dma_cache_wback_inv(_start,_size) do { } while (0)
261
262 #endif /* __KERNEL__ */
263
264 #endif
265