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[linux-2.6] / include / asm-x86 / io_32.h
1 #ifndef _ASM_IO_H
2 #define _ASM_IO_H
3
4 #include <linux/string.h>
5 #include <linux/compiler.h>
6
7 /*
8  * This file contains the definitions for the x86 IO instructions
9  * inb/inw/inl/outb/outw/outl and the "string versions" of the same
10  * (insb/insw/insl/outsb/outsw/outsl). You can also use "pausing"
11  * versions of the single-IO instructions (inb_p/inw_p/..).
12  *
13  * This file is not meant to be obfuscating: it's just complicated
14  * to (a) handle it all in a way that makes gcc able to optimize it
15  * as well as possible and (b) trying to avoid writing the same thing
16  * over and over again with slight variations and possibly making a
17  * mistake somewhere.
18  */
19
20 /*
21  * Thanks to James van Artsdalen for a better timing-fix than
22  * the two short jumps: using outb's to a nonexistent port seems
23  * to guarantee better timings even on fast machines.
24  *
25  * On the other hand, I'd like to be sure of a non-existent port:
26  * I feel a bit unsafe about using 0x80 (should be safe, though)
27  *
28  *              Linus
29  */
30
31  /*
32   *  Bit simplified and optimized by Jan Hubicka
33   *  Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999.
34   *
35   *  isa_memset_io, isa_memcpy_fromio, isa_memcpy_toio added,
36   *  isa_read[wl] and isa_write[wl] fixed
37   *  - Arnaldo Carvalho de Melo <acme@conectiva.com.br>
38   */
39
40 #define IO_SPACE_LIMIT 0xffff
41
42 #define XQUAD_PORTIO_BASE 0xfe400000
43 #define XQUAD_PORTIO_QUAD 0x40000  /* 256k per quad. */
44
45 #ifdef __KERNEL__
46
47 #include <asm-generic/iomap.h>
48
49 #include <linux/vmalloc.h>
50
51 /*
52  * Convert a virtual cached pointer to an uncached pointer
53  */
54 #define xlate_dev_kmem_ptr(p)   p
55
56 /**
57  *      virt_to_phys    -       map virtual addresses to physical
58  *      @address: address to remap
59  *
60  *      The returned physical address is the physical (CPU) mapping for
61  *      the memory address given. It is only valid to use this function on
62  *      addresses directly mapped or allocated via kmalloc.
63  *
64  *      This function does not give bus mappings for DMA transfers. In
65  *      almost all conceivable cases a device driver should not be using
66  *      this function
67  */
68
69 static inline unsigned long virt_to_phys(volatile void *address)
70 {
71         return __pa(address);
72 }
73
74 /**
75  *      phys_to_virt    -       map physical address to virtual
76  *      @address: address to remap
77  *
78  *      The returned virtual address is a current CPU mapping for
79  *      the memory address given. It is only valid to use this function on
80  *      addresses that have a kernel mapping
81  *
82  *      This function does not handle bus mappings for DMA transfers. In
83  *      almost all conceivable cases a device driver should not be using
84  *      this function
85  */
86
87 static inline void *phys_to_virt(unsigned long address)
88 {
89         return __va(address);
90 }
91
92 /*
93  * Change "struct page" to physical address.
94  */
95 #define page_to_phys(page)    ((dma_addr_t)page_to_pfn(page) << PAGE_SHIFT)
96
97 /**
98  * ioremap     -   map bus memory into CPU space
99  * @offset:    bus address of the memory
100  * @size:      size of the resource to map
101  *
102  * ioremap performs a platform specific sequence of operations to
103  * make bus memory CPU accessible via the readb/readw/readl/writeb/
104  * writew/writel functions and the other mmio helpers. The returned
105  * address is not guaranteed to be usable directly as a virtual
106  * address.
107  *
108  * If the area you are trying to map is a PCI BAR you should have a
109  * look at pci_iomap().
110  */
111 extern void __iomem *ioremap_nocache(resource_size_t offset, unsigned long size);
112 extern void __iomem *ioremap_cache(resource_size_t offset, unsigned long size);
113
114 /*
115  * The default ioremap() behavior is non-cached:
116  */
117 static inline void __iomem *ioremap(resource_size_t offset, unsigned long size)
118 {
119         return ioremap_nocache(offset, size);
120 }
121
122 extern void iounmap(volatile void __iomem *addr);
123
124 /*
125  * early_ioremap() and early_iounmap() are for temporary early boot-time
126  * mappings, before the real ioremap() is functional.
127  * A boot-time mapping is currently limited to at most 16 pages.
128  */
129 extern void early_ioremap_init(void);
130 extern void early_ioremap_clear(void);
131 extern void early_ioremap_reset(void);
132 extern void *early_ioremap(unsigned long offset, unsigned long size);
133 extern void early_iounmap(void *addr, unsigned long size);
134 extern void __iomem *fix_ioremap(unsigned idx, unsigned long phys);
135
136 /* Use early IO mappings for DMI because it's initialized early */
137 #define dmi_ioremap early_ioremap
138 #define dmi_iounmap early_iounmap
139 #define dmi_alloc alloc_bootmem
140
141 /*
142  * ISA I/O bus memory addresses are 1:1 with the physical address.
143  */
144 #define isa_virt_to_bus virt_to_phys
145 #define isa_page_to_bus page_to_phys
146 #define isa_bus_to_virt phys_to_virt
147
148 /*
149  * However PCI ones are not necessarily 1:1 and therefore these interfaces
150  * are forbidden in portable PCI drivers.
151  *
152  * Allow them on x86 for legacy drivers, though.
153  */
154 #define virt_to_bus virt_to_phys
155 #define bus_to_virt phys_to_virt
156
157 /*
158  * readX/writeX() are used to access memory mapped devices. On some
159  * architectures the memory mapped IO stuff needs to be accessed
160  * differently. On the x86 architecture, we just read/write the
161  * memory location directly.
162  */
163
164 static inline unsigned char readb(const volatile void __iomem *addr)
165 {
166         return *(volatile unsigned char __force *)addr;
167 }
168
169 static inline unsigned short readw(const volatile void __iomem *addr)
170 {
171         return *(volatile unsigned short __force *)addr;
172 }
173
174 static inline unsigned int readl(const volatile void __iomem *addr)
175 {
176         return *(volatile unsigned int __force *) addr;
177 }
178
179 #define readb_relaxed(addr) readb(addr)
180 #define readw_relaxed(addr) readw(addr)
181 #define readl_relaxed(addr) readl(addr)
182 #define __raw_readb readb
183 #define __raw_readw readw
184 #define __raw_readl readl
185
186 static inline void writeb(unsigned char b, volatile void __iomem *addr)
187 {
188         *(volatile unsigned char __force *)addr = b;
189 }
190
191 static inline void writew(unsigned short b, volatile void __iomem *addr)
192 {
193         *(volatile unsigned short __force *)addr = b;
194 }
195
196 static inline void writel(unsigned int b, volatile void __iomem *addr)
197 {
198         *(volatile unsigned int __force *)addr = b;
199 }
200 #define __raw_writeb writeb
201 #define __raw_writew writew
202 #define __raw_writel writel
203
204 #define mmiowb()
205
206 static inline void
207 memset_io(volatile void __iomem *addr, unsigned char val, int count)
208 {
209         memset((void __force *)addr, val, count);
210 }
211
212 static inline void
213 memcpy_fromio(void *dst, const volatile void __iomem *src, int count)
214 {
215         __memcpy(dst, (const void __force *)src, count);
216 }
217
218 static inline void
219 memcpy_toio(volatile void __iomem *dst, const void *src, int count)
220 {
221         __memcpy((void __force *)dst, src, count);
222 }
223
224 /*
225  * ISA space is 'always mapped' on a typical x86 system, no need to
226  * explicitly ioremap() it. The fact that the ISA IO space is mapped
227  * to PAGE_OFFSET is pure coincidence - it does not mean ISA values
228  * are physical addresses. The following constant pointer can be
229  * used as the IO-area pointer (it can be iounmapped as well, so the
230  * analogy with PCI is quite large):
231  */
232 #define __ISA_IO_base ((char __iomem *)(PAGE_OFFSET))
233
234 /*
235  *      Cache management
236  *
237  *      This needed for two cases
238  *      1. Out of order aware processors
239  *      2. Accidentally out of order processors (PPro errata #51)
240  */
241
242 #if defined(CONFIG_X86_OOSTORE) || defined(CONFIG_X86_PPRO_FENCE)
243
244 static inline void flush_write_buffers(void)
245 {
246         asm volatile("lock; addl $0,0(%%esp)": : :"memory");
247 }
248
249 #else
250
251 #define flush_write_buffers() do { } while (0)
252
253 #endif
254
255 #endif /* __KERNEL__ */
256
257 extern void native_io_delay(void);
258
259 extern int io_delay_type;
260 extern void io_delay_init(void);
261
262 #if defined(CONFIG_PARAVIRT)
263 #include <asm/paravirt.h>
264 #else
265
266 static inline void slow_down_io(void)
267 {
268         native_io_delay();
269 #ifdef REALLY_SLOW_IO
270         native_io_delay();
271         native_io_delay();
272         native_io_delay();
273 #endif
274 }
275
276 #endif
277
278 #define __BUILDIO(bwl, bw, type)                                \
279 static inline void out##bwl(unsigned type value, int port)      \
280 {                                                               \
281         out##bwl##_local(value, port);                          \
282 }                                                               \
283                                                                 \
284 static inline unsigned type in##bwl(int port)                   \
285 {                                                               \
286         return in##bwl##_local(port);                           \
287 }
288
289 #define BUILDIO(bwl, bw, type)                                          \
290 static inline void out##bwl##_local(unsigned type value, int port)      \
291 {                                                                       \
292         asm volatile("out" #bwl " %" #bw "0, %w1"               \
293                      : : "a"(value), "Nd"(port));                       \
294 }                                                                       \
295                                                                         \
296 static inline unsigned type in##bwl##_local(int port)                   \
297 {                                                                       \
298         unsigned type value;                                            \
299         asm volatile("in" #bwl " %w1, %" #bw "0"                \
300                      : "=a"(value) : "Nd"(port));                       \
301         return value;                                                   \
302 }                                                                       \
303                                                                         \
304 static inline void out##bwl##_local_p(unsigned type value, int port)    \
305 {                                                                       \
306         out##bwl##_local(value, port);                                  \
307         slow_down_io();                                                 \
308 }                                                                       \
309                                                                         \
310 static inline unsigned type in##bwl##_local_p(int port)                 \
311 {                                                                       \
312         unsigned type value = in##bwl##_local(port);                    \
313         slow_down_io();                                                 \
314         return value;                                                   \
315 }                                                                       \
316                                                                         \
317 __BUILDIO(bwl, bw, type)                                                \
318                                                                         \
319 static inline void out##bwl##_p(unsigned type value, int port)          \
320 {                                                                       \
321         out##bwl(value, port);                                          \
322         slow_down_io();                                                 \
323 }                                                                       \
324                                                                         \
325 static inline unsigned type in##bwl##_p(int port)                       \
326 {                                                                       \
327         unsigned type value = in##bwl(port);                            \
328         slow_down_io();                                                 \
329         return value;                                                   \
330 }                                                                       \
331                                                                         \
332 static inline void outs##bwl(int port, const void *addr, unsigned long count) \
333 {                                                                       \
334         asm volatile("rep; outs" #bwl                                   \
335                      : "+S"(addr), "+c"(count) : "d"(port));            \
336 }                                                                       \
337                                                                         \
338 static inline void ins##bwl(int port, void *addr, unsigned long count)  \
339 {                                                                       \
340         asm volatile("rep; ins" #bwl                                    \
341                      : "+D"(addr), "+c"(count) : "d"(port));            \
342 }
343
344 BUILDIO(b, b, char)
345 BUILDIO(w, w, short)
346 BUILDIO(l, , int)
347
348 #endif