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 physical pointer to a virtual kernel pointer for /dev/mem
53 * access
54 */
55#define xlate_dev_mem_ptr(p)	__va(p)
56
57/*
58 * Convert a virtual cached pointer to an uncached pointer
59 */
60#define xlate_dev_kmem_ptr(p)	p
61
62/**
63 *	virt_to_phys	-	map virtual addresses to physical
64 *	@address: address to remap
65 *
66 *	The returned physical address is the physical (CPU) mapping for
67 *	the memory address given. It is only valid to use this function on
68 *	addresses directly mapped or allocated via kmalloc.
69 *
70 *	This function does not give bus mappings for DMA transfers. In
71 *	almost all conceivable cases a device driver should not be using
72 *	this function
73 */
74
75static inline unsigned long virt_to_phys(volatile void * address)
76{
77	return __pa(address);
78}
79
80/**
81 *	phys_to_virt	-	map physical address to virtual
82 *	@address: address to remap
83 *
84 *	The returned virtual address is a current CPU mapping for
85 *	the memory address given. It is only valid to use this function on
86 *	addresses that have a kernel mapping
87 *
88 *	This function does not handle bus mappings for DMA transfers. In
89 *	almost all conceivable cases a device driver should not be using
90 *	this function
91 */
92
93static inline void * phys_to_virt(unsigned long address)
94{
95	return __va(address);
96}
97
98/*
99 * Change "struct page" to physical address.
100 */
101#define page_to_phys(page)    ((dma_addr_t)page_to_pfn(page) << PAGE_SHIFT)
102
103extern void __iomem * __ioremap(unsigned long offset, unsigned long size, unsigned long flags);
104
105/**
106 * ioremap     -   map bus memory into CPU space
107 * @offset:    bus address of the memory
108 * @size:      size of the resource to map
109 *
110 * ioremap performs a platform specific sequence of operations to
111 * make bus memory CPU accessible via the readb/readw/readl/writeb/
112 * writew/writel functions and the other mmio helpers. The returned
113 * address is not guaranteed to be usable directly as a virtual
114 * address.
115 *
116 * If the area you are trying to map is a PCI BAR you should have a
117 * look at pci_iomap().
118 */
119
120static inline void __iomem * ioremap(unsigned long offset, unsigned long size)
121{
122	return __ioremap(offset, size, 0);
123}
124
125extern void __iomem * ioremap_nocache(unsigned long offset, unsigned long size);
126extern void iounmap(volatile void __iomem *addr);
127
128/*
129 * bt_ioremap() and bt_iounmap() are for temporary early boot-time
130 * mappings, before the real ioremap() is functional.
131 * A boot-time mapping is currently limited to at most 16 pages.
132 */
133extern void *bt_ioremap(unsigned long offset, unsigned long size);
134extern void bt_iounmap(void *addr, unsigned long size);
135extern void __iomem *fix_ioremap(unsigned idx, unsigned long phys);
136
137/* Use early IO mappings for DMI because it's initialized early */
138#define dmi_ioremap bt_ioremap
139#define dmi_iounmap bt_iounmap
140#define dmi_alloc alloc_bootmem
141
142/*
143 * ISA I/O bus memory addresses are 1:1 with the physical address.
144 */
145#define isa_virt_to_bus virt_to_phys
146#define isa_page_to_bus page_to_phys
147#define isa_bus_to_virt phys_to_virt
148
149/*
150 * However PCI ones are not necessarily 1:1 and therefore these interfaces
151 * are forbidden in portable PCI drivers.
152 *
153 * Allow them on x86 for legacy drivers, though.
154 */
155#define virt_to_bus virt_to_phys
156#define bus_to_virt phys_to_virt
157
158/*
159 * readX/writeX() are used to access memory mapped devices. On some
160 * architectures the memory mapped IO stuff needs to be accessed
161 * differently. On the x86 architecture, we just read/write the
162 * memory location directly.
163 */
164
165static inline unsigned char readb(const volatile void __iomem *addr)
166{
167	return *(volatile unsigned char __force *) addr;
168}
169static inline unsigned short readw(const volatile void __iomem *addr)
170{
171	return *(volatile unsigned short __force *) addr;
172}
173static inline unsigned int readl(const volatile void __iomem *addr)
174{
175	return *(volatile unsigned int __force *) addr;
176}
177#define readb_relaxed(addr) readb(addr)
178#define readw_relaxed(addr) readw(addr)
179#define readl_relaxed(addr) readl(addr)
180#define __raw_readb readb
181#define __raw_readw readw
182#define __raw_readl readl
183
184static inline void writeb(unsigned char b, volatile void __iomem *addr)
185{
186	*(volatile unsigned char __force *) addr = b;
187}
188static inline void writew(unsigned short b, volatile void __iomem *addr)
189{
190	*(volatile unsigned short __force *) addr = b;
191}
192static inline void writel(unsigned int b, volatile void __iomem *addr)
193{
194	*(volatile unsigned int __force *) addr = b;
195}
196#define __raw_writeb writeb
197#define __raw_writew writew
198#define __raw_writel writel
199
200#define mmiowb()
201
202static inline void
203memset_io(volatile void __iomem *addr, unsigned char val, int count)
204{
205	memset((void __force *)addr, val, count);
206}
207
208static inline void
209memcpy_fromio(void *dst, const volatile void __iomem *src, int count)
210{
211	__memcpy(dst, (const void __force *)src, count);
212}
213
214static inline void
215memcpy_toio(volatile void __iomem *dst, const void *src, int count)
216{
217	__memcpy((void __force *)dst, src, count);
218}
219
220/*
221 * ISA space is 'always mapped' on a typical x86 system, no need to
222 * explicitly ioremap() it. The fact that the ISA IO space is mapped
223 * to PAGE_OFFSET is pure coincidence - it does not mean ISA values
224 * are physical addresses. The following constant pointer can be
225 * used as the IO-area pointer (it can be iounmapped as well, so the
226 * analogy with PCI is quite large):
227 */
228#define __ISA_IO_base ((char __iomem *)(PAGE_OFFSET))
229
230/*
231 *	Cache management
232 *
233 *	This needed for two cases
234 *	1. Out of order aware processors
235 *	2. Accidentally out of order processors (PPro errata #51)
236 */
237
238#if defined(CONFIG_X86_OOSTORE) || defined(CONFIG_X86_PPRO_FENCE)
239
240static inline void flush_write_buffers(void)
241{
242	__asm__ __volatile__ ("lock; addl $0,0(%%esp)": : :"memory");
243}
244
245#else
246
247#define flush_write_buffers() do { } while (0)
248
249#endif
250
251#endif /* __KERNEL__ */
252
253static inline void native_io_delay(void)
254{
255	asm volatile("outb %%al,$0x80" : : : "memory");
256}
257
258#if defined(CONFIG_PARAVIRT)
259#include <asm/paravirt.h>
260#else
261
262static inline void slow_down_io(void) {
263	native_io_delay();
264#ifdef REALLY_SLOW_IO
265	native_io_delay();
266	native_io_delay();
267	native_io_delay();
268#endif
269}
270
271#endif
272
273#ifdef CONFIG_X86_NUMAQ
274extern void *xquad_portio;    /* Where the IO area was mapped */
275#define XQUAD_PORT_ADDR(port, quad) (xquad_portio + (XQUAD_PORTIO_QUAD*quad) + port)
276#define __BUILDIO(bwl,bw,type) \
277static inline void out##bwl##_quad(unsigned type value, int port, int quad) { \
278	if (xquad_portio) \
279		write##bwl(value, XQUAD_PORT_ADDR(port, quad)); \
280	else \
281		out##bwl##_local(value, port); \
282} \
283static inline void out##bwl(unsigned type value, int port) { \
284	out##bwl##_quad(value, port, 0); \
285} \
286static inline unsigned type in##bwl##_quad(int port, int quad) { \
287	if (xquad_portio) \
288		return read##bwl(XQUAD_PORT_ADDR(port, quad)); \
289	else \
290		return in##bwl##_local(port); \
291} \
292static inline unsigned type in##bwl(int port) { \
293	return in##bwl##_quad(port, 0); \
294}
295#else
296#define __BUILDIO(bwl,bw,type) \
297static inline void out##bwl(unsigned type value, int port) { \
298	out##bwl##_local(value, port); \
299} \
300static inline unsigned type in##bwl(int port) { \
301	return in##bwl##_local(port); \
302}
303#endif
304
305
306#define BUILDIO(bwl,bw,type) \
307static inline void out##bwl##_local(unsigned type value, int port) { \
308	__asm__ __volatile__("out" #bwl " %" #bw "0, %w1" : : "a"(value), "Nd"(port)); \
309} \
310static inline unsigned type in##bwl##_local(int port) { \
311	unsigned type value; \
312	__asm__ __volatile__("in" #bwl " %w1, %" #bw "0" : "=a"(value) : "Nd"(port)); \
313	return value; \
314} \
315static inline void out##bwl##_local_p(unsigned type value, int port) { \
316	out##bwl##_local(value, port); \
317	slow_down_io(); \
318} \
319static inline unsigned type in##bwl##_local_p(int port) { \
320	unsigned type value = in##bwl##_local(port); \
321	slow_down_io(); \
322	return value; \
323} \
324__BUILDIO(bwl,bw,type) \
325static inline void out##bwl##_p(unsigned type value, int port) { \
326	out##bwl(value, port); \
327	slow_down_io(); \
328} \
329static inline unsigned type in##bwl##_p(int port) { \
330	unsigned type value = in##bwl(port); \
331	slow_down_io(); \
332	return value; \
333} \
334static inline void outs##bwl(int port, const void *addr, unsigned long count) { \
335	__asm__ __volatile__("rep; outs" #bwl : "+S"(addr), "+c"(count) : "d"(port)); \
336} \
337static inline void ins##bwl(int port, void *addr, unsigned long count) { \
338	__asm__ __volatile__("rep; ins" #bwl : "+D"(addr), "+c"(count) : "d"(port)); \
339}
340
341BUILDIO(b,b,char)
342BUILDIO(w,w,short)
343BUILDIO(l,,int)
344
345#endif
346