xref: /linux/arch/x86/include/asm/io.h (revision f3a8b6645dc2e60d11f20c1c23afd964ff4e55ae)
1 #ifndef _ASM_X86_IO_H
2 #define _ASM_X86_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 ARCH_HAS_IOREMAP_WC
38 #define ARCH_HAS_IOREMAP_WT
39 
40 #include <linux/string.h>
41 #include <linux/compiler.h>
42 #include <asm/page.h>
43 #include <asm/early_ioremap.h>
44 #include <asm/pgtable_types.h>
45 
46 #define build_mmio_read(name, size, type, reg, barrier) \
47 static inline type name(const volatile void __iomem *addr) \
48 { type ret; asm volatile("mov" size " %1,%0":reg (ret) \
49 :"m" (*(volatile type __force *)addr) barrier); return ret; }
50 
51 #define build_mmio_write(name, size, type, reg, barrier) \
52 static inline void name(type val, volatile void __iomem *addr) \
53 { asm volatile("mov" size " %0,%1": :reg (val), \
54 "m" (*(volatile type __force *)addr) barrier); }
55 
56 build_mmio_read(readb, "b", unsigned char, "=q", :"memory")
57 build_mmio_read(readw, "w", unsigned short, "=r", :"memory")
58 build_mmio_read(readl, "l", unsigned int, "=r", :"memory")
59 
60 build_mmio_read(__readb, "b", unsigned char, "=q", )
61 build_mmio_read(__readw, "w", unsigned short, "=r", )
62 build_mmio_read(__readl, "l", unsigned int, "=r", )
63 
64 build_mmio_write(writeb, "b", unsigned char, "q", :"memory")
65 build_mmio_write(writew, "w", unsigned short, "r", :"memory")
66 build_mmio_write(writel, "l", unsigned int, "r", :"memory")
67 
68 build_mmio_write(__writeb, "b", unsigned char, "q", )
69 build_mmio_write(__writew, "w", unsigned short, "r", )
70 build_mmio_write(__writel, "l", unsigned int, "r", )
71 
72 #define readb_relaxed(a) __readb(a)
73 #define readw_relaxed(a) __readw(a)
74 #define readl_relaxed(a) __readl(a)
75 #define __raw_readb __readb
76 #define __raw_readw __readw
77 #define __raw_readl __readl
78 
79 #define writeb_relaxed(v, a) __writeb(v, a)
80 #define writew_relaxed(v, a) __writew(v, a)
81 #define writel_relaxed(v, a) __writel(v, a)
82 #define __raw_writeb __writeb
83 #define __raw_writew __writew
84 #define __raw_writel __writel
85 
86 #define mmiowb() barrier()
87 
88 #ifdef CONFIG_X86_64
89 
90 build_mmio_read(readq, "q", unsigned long, "=r", :"memory")
91 build_mmio_write(writeq, "q", unsigned long, "r", :"memory")
92 
93 #define readq_relaxed(a)	readq(a)
94 #define writeq_relaxed(v, a)	writeq(v, a)
95 
96 #define __raw_readq(a)		readq(a)
97 #define __raw_writeq(val, addr)	writeq(val, addr)
98 
99 /* Let people know that we have them */
100 #define readq			readq
101 #define writeq			writeq
102 
103 #endif
104 
105 /**
106  *	virt_to_phys	-	map virtual addresses to physical
107  *	@address: address to remap
108  *
109  *	The returned physical address is the physical (CPU) mapping for
110  *	the memory address given. It is only valid to use this function on
111  *	addresses directly mapped or allocated via kmalloc.
112  *
113  *	This function does not give bus mappings for DMA transfers. In
114  *	almost all conceivable cases a device driver should not be using
115  *	this function
116  */
117 
118 static inline phys_addr_t virt_to_phys(volatile void *address)
119 {
120 	return __pa(address);
121 }
122 
123 /**
124  *	phys_to_virt	-	map physical address to virtual
125  *	@address: address to remap
126  *
127  *	The returned virtual address is a current CPU mapping for
128  *	the memory address given. It is only valid to use this function on
129  *	addresses that have a kernel mapping
130  *
131  *	This function does not handle bus mappings for DMA transfers. In
132  *	almost all conceivable cases a device driver should not be using
133  *	this function
134  */
135 
136 static inline void *phys_to_virt(phys_addr_t address)
137 {
138 	return __va(address);
139 }
140 
141 /*
142  * Change "struct page" to physical address.
143  */
144 #define page_to_phys(page)    ((dma_addr_t)page_to_pfn(page) << PAGE_SHIFT)
145 
146 /*
147  * ISA I/O bus memory addresses are 1:1 with the physical address.
148  * However, we truncate the address to unsigned int to avoid undesirable
149  * promitions in legacy drivers.
150  */
151 static inline unsigned int isa_virt_to_bus(volatile void *address)
152 {
153 	return (unsigned int)virt_to_phys(address);
154 }
155 #define isa_page_to_bus(page)	((unsigned int)page_to_phys(page))
156 #define isa_bus_to_virt		phys_to_virt
157 
158 /*
159  * However PCI ones are not necessarily 1:1 and therefore these interfaces
160  * are forbidden in portable PCI drivers.
161  *
162  * Allow them on x86 for legacy drivers, though.
163  */
164 #define virt_to_bus virt_to_phys
165 #define bus_to_virt phys_to_virt
166 
167 /**
168  * ioremap     -   map bus memory into CPU space
169  * @offset:    bus address of the memory
170  * @size:      size of the resource to map
171  *
172  * ioremap performs a platform specific sequence of operations to
173  * make bus memory CPU accessible via the readb/readw/readl/writeb/
174  * writew/writel functions and the other mmio helpers. The returned
175  * address is not guaranteed to be usable directly as a virtual
176  * address.
177  *
178  * If the area you are trying to map is a PCI BAR you should have a
179  * look at pci_iomap().
180  */
181 extern void __iomem *ioremap_nocache(resource_size_t offset, unsigned long size);
182 extern void __iomem *ioremap_uc(resource_size_t offset, unsigned long size);
183 #define ioremap_uc ioremap_uc
184 
185 extern void __iomem *ioremap_cache(resource_size_t offset, unsigned long size);
186 extern void __iomem *ioremap_prot(resource_size_t offset, unsigned long size,
187 				unsigned long prot_val);
188 
189 /*
190  * The default ioremap() behavior is non-cached:
191  */
192 static inline void __iomem *ioremap(resource_size_t offset, unsigned long size)
193 {
194 	return ioremap_nocache(offset, size);
195 }
196 
197 extern void iounmap(volatile void __iomem *addr);
198 
199 extern void set_iounmap_nonlazy(void);
200 
201 #ifdef __KERNEL__
202 
203 #include <asm-generic/iomap.h>
204 
205 /*
206  * Convert a virtual cached pointer to an uncached pointer
207  */
208 #define xlate_dev_kmem_ptr(p)	p
209 
210 static inline void
211 memset_io(volatile void __iomem *addr, unsigned char val, size_t count)
212 {
213 	memset((void __force *)addr, val, count);
214 }
215 
216 static inline void
217 memcpy_fromio(void *dst, const volatile void __iomem *src, size_t count)
218 {
219 	memcpy(dst, (const void __force *)src, count);
220 }
221 
222 static inline void
223 memcpy_toio(volatile void __iomem *dst, const void *src, size_t count)
224 {
225 	memcpy((void __force *)dst, src, count);
226 }
227 
228 /*
229  * ISA space is 'always mapped' on a typical x86 system, no need to
230  * explicitly ioremap() it. The fact that the ISA IO space is mapped
231  * to PAGE_OFFSET is pure coincidence - it does not mean ISA values
232  * are physical addresses. The following constant pointer can be
233  * used as the IO-area pointer (it can be iounmapped as well, so the
234  * analogy with PCI is quite large):
235  */
236 #define __ISA_IO_base ((char __iomem *)(PAGE_OFFSET))
237 
238 /*
239  *	Cache management
240  *
241  *	This needed for two cases
242  *	1. Out of order aware processors
243  *	2. Accidentally out of order processors (PPro errata #51)
244  */
245 
246 static inline void flush_write_buffers(void)
247 {
248 #if defined(CONFIG_X86_PPRO_FENCE)
249 	asm volatile("lock; addl $0,0(%%esp)": : :"memory");
250 #endif
251 }
252 
253 #endif /* __KERNEL__ */
254 
255 extern void native_io_delay(void);
256 
257 extern int io_delay_type;
258 extern void io_delay_init(void);
259 
260 #if defined(CONFIG_PARAVIRT)
261 #include <asm/paravirt.h>
262 #else
263 
264 static inline void slow_down_io(void)
265 {
266 	native_io_delay();
267 #ifdef REALLY_SLOW_IO
268 	native_io_delay();
269 	native_io_delay();
270 	native_io_delay();
271 #endif
272 }
273 
274 #endif
275 
276 #define BUILDIO(bwl, bw, type)						\
277 static inline void out##bwl(unsigned type value, int port)		\
278 {									\
279 	asm volatile("out" #bwl " %" #bw "0, %w1"			\
280 		     : : "a"(value), "Nd"(port));			\
281 }									\
282 									\
283 static inline unsigned type in##bwl(int port)				\
284 {									\
285 	unsigned type value;						\
286 	asm volatile("in" #bwl " %w1, %" #bw "0"			\
287 		     : "=a"(value) : "Nd"(port));			\
288 	return value;							\
289 }									\
290 									\
291 static inline void out##bwl##_p(unsigned type value, int port)		\
292 {									\
293 	out##bwl(value, port);						\
294 	slow_down_io();							\
295 }									\
296 									\
297 static inline unsigned type in##bwl##_p(int port)			\
298 {									\
299 	unsigned type value = in##bwl(port);				\
300 	slow_down_io();							\
301 	return value;							\
302 }									\
303 									\
304 static inline void outs##bwl(int port, const void *addr, unsigned long count) \
305 {									\
306 	asm volatile("rep; outs" #bwl					\
307 		     : "+S"(addr), "+c"(count) : "d"(port));		\
308 }									\
309 									\
310 static inline void ins##bwl(int port, void *addr, unsigned long count)	\
311 {									\
312 	asm volatile("rep; ins" #bwl					\
313 		     : "+D"(addr), "+c"(count) : "d"(port));		\
314 }
315 
316 BUILDIO(b, b, char)
317 BUILDIO(w, w, short)
318 BUILDIO(l, , int)
319 
320 extern void *xlate_dev_mem_ptr(phys_addr_t phys);
321 extern void unxlate_dev_mem_ptr(phys_addr_t phys, void *addr);
322 
323 extern int ioremap_change_attr(unsigned long vaddr, unsigned long size,
324 				enum page_cache_mode pcm);
325 extern void __iomem *ioremap_wc(resource_size_t offset, unsigned long size);
326 extern void __iomem *ioremap_wt(resource_size_t offset, unsigned long size);
327 
328 extern bool is_early_ioremap_ptep(pte_t *ptep);
329 
330 #ifdef CONFIG_XEN
331 #include <xen/xen.h>
332 struct bio_vec;
333 
334 extern bool xen_biovec_phys_mergeable(const struct bio_vec *vec1,
335 				      const struct bio_vec *vec2);
336 
337 #define BIOVEC_PHYS_MERGEABLE(vec1, vec2)				\
338 	(__BIOVEC_PHYS_MERGEABLE(vec1, vec2) &&				\
339 	 (!xen_domain() || xen_biovec_phys_mergeable(vec1, vec2)))
340 #endif	/* CONFIG_XEN */
341 
342 #define IO_SPACE_LIMIT 0xffff
343 
344 #ifdef CONFIG_MTRR
345 extern int __must_check arch_phys_wc_index(int handle);
346 #define arch_phys_wc_index arch_phys_wc_index
347 
348 extern int __must_check arch_phys_wc_add(unsigned long base,
349 					 unsigned long size);
350 extern void arch_phys_wc_del(int handle);
351 #define arch_phys_wc_add arch_phys_wc_add
352 #endif
353 
354 #ifdef CONFIG_X86_PAT
355 extern int arch_io_reserve_memtype_wc(resource_size_t start, resource_size_t size);
356 extern void arch_io_free_memtype_wc(resource_size_t start, resource_size_t size);
357 #define arch_io_reserve_memtype_wc arch_io_reserve_memtype_wc
358 #endif
359 
360 #endif /* _ASM_X86_IO_H */
361