xref: /titanic_50/usr/src/grub/grub-0.97/netboot/io.h (revision eab227978ccdaa5a7cc9fd92ace768915dae3a2b)
1 #include <sys/ccompile.h>
2 
3 #ifndef	IO_H
4 #define IO_H
5 
6 /* Amount of relocation etherboot is experiencing */
7 extern unsigned long virt_offset;
8 
9 /* Don't require identity mapped physical memory,
10  * osloader.c is the only valid user at the moment.
11  */
12 unsigned long virt_to_phys(volatile const void *virt_addr);
13 void *phys_to_virt(unsigned long phys_addr);
14 
15 /* virt_to_bus converts an addresss inside of etherboot [_start, _end]
16  * into a memory access cards can use.
17  */
18 #define virt_to_bus virt_to_phys
19 
20 
21 /* bus_to_virt reverses virt_to_bus, the address must be output
22  * from virt_to_bus to be valid.  This function does not work on
23  * all bus addresses.
24  */
25 #define bus_to_virt phys_to_virt
26 
27 /* ioremap converts a random 32bit bus address into something
28  * etherboot can access.
29  */
30 static inline void *ioremap(unsigned long bus_addr, unsigned long length __unused)
31 {
32 	return bus_to_virt(bus_addr);
33 }
34 
35 /* iounmap cleans up anything ioremap had to setup */
36 static inline void iounmap(void *virt_addr __unused)
37 {
38 	return;
39 }
40 
41 /*
42  * This file contains the definitions for the x86 IO instructions
43  * inb/inw/inl/outb/outw/outl and the "string versions" of the same
44  * (insb/insw/insl/outsb/outsw/outsl). You can also use "pausing"
45  * versions of the single-IO instructions (inb_p/inw_p/..).
46  *
47  * This file is not meant to be obfuscating: it's just complicated
48  * to (a) handle it all in a way that makes gcc able to optimize it
49  * as well as possible and (b) trying to avoid writing the same thing
50  * over and over again with slight variations and possibly making a
51  * mistake somewhere.
52  */
53 
54 /*
55  * Thanks to James van Artsdalen for a better timing-fix than
56  * the two short jumps: using outb's to a nonexistent port seems
57  * to guarantee better timings even on fast machines.
58  *
59  * On the other hand, I'd like to be sure of a non-existent port:
60  * I feel a bit unsafe about using 0x80 (should be safe, though)
61  *
62  *		Linus
63  */
64 
65 #ifdef	SLOW_IO_BY_JUMPING
66 #define __SLOW_DOWN_IO __asm__ __volatile__("jmp 1f\n1:\tjmp 1f\n1:")
67 #else
68 #define __SLOW_DOWN_IO __asm__ __volatile__("outb %al,$0x80")
69 #endif
70 
71 #ifdef	REALLY_SLOW_IO
72 #define SLOW_DOWN_IO { __SLOW_DOWN_IO; __SLOW_DOWN_IO; __SLOW_DOWN_IO; __SLOW_DOWN_IO; }
73 #else
74 #define SLOW_DOWN_IO __SLOW_DOWN_IO
75 #endif
76 
77 /*
78  * readX/writeX() are used to access memory mapped devices. On some
79  * architectures the memory mapped IO stuff needs to be accessed
80  * differently. On the x86 architecture, we just read/write the
81  * memory location directly.
82  */
83 #define readb(addr) (*(volatile unsigned char *) (addr))
84 #define readw(addr) (*(volatile unsigned short *) (addr))
85 #define readl(addr) (*(volatile unsigned int *) (addr))
86 
87 #define writeb(b,addr) ((*(volatile unsigned char *) (addr)) = (b))
88 #define writew(b,addr) ((*(volatile unsigned short *) (addr)) = (b))
89 #define writel(b,addr) ((*(volatile unsigned int *) (addr)) = (b))
90 
91 #define memcpy_fromio(a,b,c)	memcpy((a),(void *)(b),(c))
92 #define memcpy_toio(a,b,c)	memcpy((void *)(a),(b),(c))
93 
94 /*
95  * Force strict CPU ordering.
96  * And yes, this is required on UP too when we're talking
97  * to devices.
98  *
99  * For now, "wmb()" doesn't actually do anything, as all
100  * Intel CPU's follow what Intel calls a *Processor Order*,
101  * in which all writes are seen in the program order even
102  * outside the CPU.
103  *
104  * I expect future Intel CPU's to have a weaker ordering,
105  * but I'd also expect them to finally get their act together
106  * and add some real memory barriers if so.
107  *
108  * Some non intel clones support out of order store. wmb() ceases to be a
109  * nop for these.
110  */
111 
112 #define mb() 	__asm__ __volatile__ ("lock; addl $0,0(%%esp)": : :"memory")
113 #define rmb()	mb()
114 #define wmb()	mb();
115 
116 
117 /*
118  * Talk about misusing macros..
119  */
120 
121 #define __OUT1(s,x) \
122 extern void __out##s(unsigned x value, unsigned short port); \
123 extern __GNU_INLINE \
124 void __out##s(unsigned x value, unsigned short port) {
125 
126 #define __OUT2(s,s1,s2) \
127 __asm__ __volatile__ ("out" #s " %" s1 "0,%" s2 "1"
128 
129 #define __OUT(s,s1,x) \
130 __OUT1(s,x) __OUT2(s,s1,"w") : : "a" (value), "d" (port)); } \
131 __OUT1(s##c,x) __OUT2(s,s1,"") : : "a" (value), "id" (port)); } \
132 __OUT1(s##_p,x) __OUT2(s,s1,"w") : : "a" (value), "d" (port)); SLOW_DOWN_IO; } \
133 __OUT1(s##c_p,x) __OUT2(s,s1,"") : : "a" (value), "id" (port)); SLOW_DOWN_IO; }
134 
135 #define __IN1(s,x) \
136 extern unsigned x __in##s(unsigned short port); \
137 extern __GNU_INLINE \
138 unsigned x __in##s(unsigned short port) { unsigned x _v;
139 
140 #define __IN2(s,s1,s2) \
141 __asm__ __volatile__ ("in" #s " %" s2 "1,%" s1 "0"
142 
143 #define __IN(s,s1,x,i...) \
144 __IN1(s,x) __IN2(s,s1,"w") : "=a" (_v) : "d" (port) ,##i ); return _v; } \
145 __IN1(s##c,x) __IN2(s,s1,"") : "=a" (_v) : "id" (port) ,##i ); return _v; } \
146 __IN1(s##_p,x) __IN2(s,s1,"w") : "=a" (_v) : "d" (port) ,##i ); SLOW_DOWN_IO; return _v; } \
147 __IN1(s##c_p,x) __IN2(s,s1,"") : "=a" (_v) : "id" (port) ,##i ); SLOW_DOWN_IO; return _v; }
148 
149 #define __INS(s) \
150 extern void ins##s(unsigned short port, void * addr, unsigned long count); \
151 extern __GNU_INLINE \
152 void ins##s(unsigned short port, void * addr, unsigned long count)	\
153 { __asm__ __volatile__ ("cld ; rep ; ins" #s \
154 : "=D" (addr), "=c" (count) : "d" (port),"0" (addr),"1" (count)); }
155 
156 #define __OUTS(s) \
157 extern void outs##s(unsigned short port, const void * addr, unsigned long  count); \
158 extern __GNU_INLINE \
159 void outs##s(unsigned short port, const void * addr, unsigned long count) \
160 { __asm__ __volatile__ ("cld ; rep ; outs" #s \
161 : "=S" (addr), "=c" (count) : "d" (port),"0" (addr),"1" (count)); }
162 
163 __IN(b,"", char)
164 __IN(w,"",short)
165 __IN(l,"", long)
166 
167 __OUT(b,"b",char)
168 __OUT(w,"w",short)
169 __OUT(l,,int)
170 
171 __INS(b)
172 __INS(w)
173 __INS(l)
174 
175 __OUTS(b)
176 __OUTS(w)
177 __OUTS(l)
178 
179 /*
180  * Note that due to the way __builtin_constant_p() works, you
181  *  - can't use it inside a inline function (it will never be true)
182  *  - you don't have to worry about side effects within the __builtin..
183  */
184 #define outb(val,port) \
185 ((__builtin_constant_p((port)) && (port) < 256) ? \
186 	__outbc((val),(port)) : \
187 	__outb((val),(port)))
188 
189 #define inb(port) \
190 ((__builtin_constant_p((port)) && (port) < 256) ? \
191 	__inbc(port) : \
192 	__inb(port))
193 
194 #define outb_p(val,port) \
195 ((__builtin_constant_p((port)) && (port) < 256) ? \
196 	__outbc_p((val),(port)) : \
197 	__outb_p((val),(port)))
198 
199 #define inb_p(port) \
200 ((__builtin_constant_p((port)) && (port) < 256) ? \
201 	__inbc_p(port) : \
202 	__inb_p(port))
203 
204 #define outw(val,port) \
205 ((__builtin_constant_p((port)) && (port) < 256) ? \
206 	__outwc((val),(port)) : \
207 	__outw((val),(port)))
208 
209 #define inw(port) \
210 ((__builtin_constant_p((port)) && (port) < 256) ? \
211 	__inwc(port) : \
212 	__inw(port))
213 
214 #define outw_p(val,port) \
215 ((__builtin_constant_p((port)) && (port) < 256) ? \
216 	__outwc_p((val),(port)) : \
217 	__outw_p((val),(port)))
218 
219 #define inw_p(port) \
220 ((__builtin_constant_p((port)) && (port) < 256) ? \
221 	__inwc_p(port) : \
222 	__inw_p(port))
223 
224 #define outl(val,port) \
225 ((__builtin_constant_p((port)) && (port) < 256) ? \
226 	__outlc((val),(port)) : \
227 	__outl((val),(port)))
228 
229 #define inl(port) \
230 ((__builtin_constant_p((port)) && (port) < 256) ? \
231 	__inlc(port) : \
232 	__inl(port))
233 
234 #define outl_p(val,port) \
235 ((__builtin_constant_p((port)) && (port) < 256) ? \
236 	__outlc_p((val),(port)) : \
237 	__outl_p((val),(port)))
238 
239 #define inl_p(port) \
240 ((__builtin_constant_p((port)) && (port) < 256) ? \
241 	__inlc_p(port) : \
242 	__inl_p(port))
243 
244 #endif /* ETHERBOOT_IO_H */
245