xref: /openbmc/u-boot/arch/x86/include/asm/io.h (revision c6af2e7d)
1 #ifndef _ASM_IO_H
2 #define _ASM_IO_H
3 
4 /*
5  * This file contains the definitions for the x86 IO instructions
6  * inb/inw/inl/outb/outw/outl and the "string versions" of the same
7  * (insb/insw/insl/outsb/outsw/outsl). You can also use "pausing"
8  * versions of the single-IO instructions (inb_p/inw_p/..).
9  *
10  * This file is not meant to be obfuscating: it's just complicated
11  * to (a) handle it all in a way that makes gcc able to optimize it
12  * as well as possible and (b) trying to avoid writing the same thing
13  * over and over again with slight variations and possibly making a
14  * mistake somewhere.
15  */
16 
17 /*
18  * Thanks to James van Artsdalen for a better timing-fix than
19  * the two short jumps: using outb's to a nonexistent port seems
20  * to guarantee better timings even on fast machines.
21  *
22  * On the other hand, I'd like to be sure of a non-existent port:
23  * I feel a bit unsafe about using 0x80 (should be safe, though)
24  *
25  *		Linus
26  */
27 
28  /*
29   *  Bit simplified and optimized by Jan Hubicka
30   *  Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999.
31   *
32   *  isa_memset_io, isa_memcpy_fromio, isa_memcpy_toio added,
33   *  isa_read[wl] and isa_write[wl] fixed
34   *  - Arnaldo Carvalho de Melo <acme@conectiva.com.br>
35   */
36 
37 #define IO_SPACE_LIMIT 0xffff
38 
39 
40 #ifdef __KERNEL__
41 
42 
43 /*
44  * readX/writeX() are used to access memory mapped devices. On some
45  * architectures the memory mapped IO stuff needs to be accessed
46  * differently. On the x86 architecture, we just read/write the
47  * memory location directly.
48  */
49 
50 #define readb(addr) (*(volatile unsigned char *) (addr))
51 #define readw(addr) (*(volatile unsigned short *) (addr))
52 #define readl(addr) (*(volatile unsigned int *) (addr))
53 #define __raw_readb readb
54 #define __raw_readw readw
55 #define __raw_readl readl
56 
57 #define writeb(b,addr) (*(volatile unsigned char *) (addr) = (b))
58 #define writew(b,addr) (*(volatile unsigned short *) (addr) = (b))
59 #define writel(b,addr) (*(volatile unsigned int *) (addr) = (b))
60 #define __raw_writeb writeb
61 #define __raw_writew writew
62 #define __raw_writel writel
63 
64 #define memset_io(a,b,c)	memset((a),(b),(c))
65 #define memcpy_fromio(a,b,c)	memcpy((a),(b),(c))
66 #define memcpy_toio(a,b,c)	memcpy((a),(b),(c))
67 
68 /*
69  * ISA space is 'always mapped' on a typical x86 system, no need to
70  * explicitly ioremap() it. The fact that the ISA IO space is mapped
71  * to PAGE_OFFSET is pure coincidence - it does not mean ISA values
72  * are physical addresses. The following constant pointer can be
73  * used as the IO-area pointer (it can be iounmapped as well, so the
74  * analogy with PCI is quite large):
75  */
76 #define isa_readb(a) readb((a))
77 #define isa_readw(a) readw((a))
78 #define isa_readl(a) readl((a))
79 #define isa_writeb(b,a) writeb(b,(a))
80 #define isa_writew(w,a) writew(w,(a))
81 #define isa_writel(l,a) writel(l,(a))
82 #define isa_memset_io(a,b,c)		memset_io((a),(b),(c))
83 #define isa_memcpy_fromio(a,b,c)	memcpy_fromio((a),(b),(c))
84 #define isa_memcpy_toio(a,b,c)		memcpy_toio((a),(b),(c))
85 
86 
87 static inline int check_signature(unsigned long io_addr,
88 	const unsigned char *signature, int length)
89 {
90 	int retval = 0;
91 	do {
92 		if (readb(io_addr) != *signature)
93 			goto out;
94 		io_addr++;
95 		signature++;
96 		length--;
97 	} while (length);
98 	retval = 1;
99 out:
100 	return retval;
101 }
102 
103 /**
104  *	isa_check_signature		-	find BIOS signatures
105  *	@io_addr: mmio address to check
106  *	@signature:  signature block
107  *	@length: length of signature
108  *
109  *	Perform a signature comparison with the ISA mmio address io_addr.
110  *	Returns 1 on a match.
111  *
112  *	This function is deprecated. New drivers should use ioremap and
113  *	check_signature.
114  */
115 
116 
117 static inline int isa_check_signature(unsigned long io_addr,
118 	const unsigned char *signature, int length)
119 {
120 	int retval = 0;
121 	do {
122 		if (isa_readb(io_addr) != *signature)
123 			goto out;
124 		io_addr++;
125 		signature++;
126 		length--;
127 	} while (length);
128 	retval = 1;
129 out:
130 	return retval;
131 }
132 
133 #endif /* __KERNEL__ */
134 
135 #ifdef SLOW_IO_BY_JUMPING
136 #define __SLOW_DOWN_IO "\njmp 1f\n1:\tjmp 1f\n1:"
137 #else
138 #define __SLOW_DOWN_IO "\noutb %%al,$0x80"
139 #endif
140 
141 #ifdef REALLY_SLOW_IO
142 #define __FULL_SLOW_DOWN_IO __SLOW_DOWN_IO __SLOW_DOWN_IO __SLOW_DOWN_IO __SLOW_DOWN_IO
143 #else
144 #define __FULL_SLOW_DOWN_IO __SLOW_DOWN_IO
145 #endif
146 
147 
148 /*
149  * Talk about misusing macros..
150  */
151 #define __OUT1(s,x) \
152 static inline void out##s(unsigned x value, unsigned short port) {
153 
154 #define __OUT2(s,s1,s2) \
155 __asm__ __volatile__ ("out" #s " %" s1 "0,%" s2 "1"
156 
157 
158 #define __OUT(s,s1,x) \
159 __OUT1(s,x) __OUT2(s,s1,"w") : : "a" (value), "Nd" (port)); } \
160 __OUT1(s##_p,x) __OUT2(s,s1,"w") __FULL_SLOW_DOWN_IO : : "a" (value), "Nd" (port));}
161 
162 #define __IN1(s) \
163 static inline RETURN_TYPE in##s(unsigned short port) { RETURN_TYPE _v;
164 
165 #define __IN2(s,s1,s2) \
166 __asm__ __volatile__ ("in" #s " %" s2 "1,%" s1 "0"
167 
168 #define __IN(s,s1,i...) \
169 __IN1(s) __IN2(s,s1,"w") : "=a" (_v) : "Nd" (port) ,##i ); return _v; } \
170 __IN1(s##_p) __IN2(s,s1,"w") __FULL_SLOW_DOWN_IO : "=a" (_v) : "Nd" (port) ,##i ); return _v; }
171 
172 #define __INS(s) \
173 static inline void ins##s(unsigned short port, void * addr, unsigned long count) \
174 { __asm__ __volatile__ ("rep ; ins" #s \
175 : "=D" (addr), "=c" (count) : "d" (port),"0" (addr),"1" (count)); }
176 
177 #define __OUTS(s) \
178 static inline void outs##s(unsigned short port, const void * addr, unsigned long count) \
179 { __asm__ __volatile__ ("rep ; outs" #s \
180 : "=S" (addr), "=c" (count) : "d" (port),"0" (addr),"1" (count)); }
181 
182 #define RETURN_TYPE unsigned char
183 __IN(b,"")
184 #undef RETURN_TYPE
185 #define RETURN_TYPE unsigned short
186 __IN(w,"")
187 #undef RETURN_TYPE
188 #define RETURN_TYPE unsigned int
189 __IN(l,"")
190 #undef RETURN_TYPE
191 
192 __OUT(b,"b",char)
193 __OUT(w,"w",short)
194 __OUT(l,,int)
195 
196 __INS(b)
197 __INS(w)
198 __INS(l)
199 
200 __OUTS(b)
201 __OUTS(w)
202 __OUTS(l)
203 
204 static inline void sync(void)
205 {
206 }
207 
208 /*
209  * Given a physical address and a length, return a virtual address
210  * that can be used to access the memory range with the caching
211  * properties specified by "flags".
212  */
213 #define MAP_NOCACHE	(0)
214 #define MAP_WRCOMBINE	(0)
215 #define MAP_WRBACK	(0)
216 #define MAP_WRTHROUGH	(0)
217 
218 static inline void *
219 map_physmem(phys_addr_t paddr, unsigned long len, unsigned long flags)
220 {
221 	return (void *)paddr;
222 }
223 
224 /*
225  * Take down a mapping set up by map_physmem().
226  */
227 static inline void unmap_physmem(void *vaddr, unsigned long flags)
228 {
229 
230 }
231 
232 static inline phys_addr_t virt_to_phys(void * vaddr)
233 {
234 	return (phys_addr_t)(vaddr);
235 }
236 
237 #endif
238