xref: /linux/arch/x86/include/asm/io.h (revision fb2ac84f8acccdec644d26dfc8ba6554f30cd6c0)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_X86_IO_H
3 #define _ASM_X86_IO_H
4 
5 /*
6  * This file contains the definitions for the x86 IO instructions
7  * inb/inw/inl/outb/outw/outl and the "string versions" of the same
8  * (insb/insw/insl/outsb/outsw/outsl). You can also use "pausing"
9  * versions of the single-IO instructions (inb_p/inw_p/..).
10  *
11  * This file is not meant to be obfuscating: it's just complicated
12  * to (a) handle it all in a way that makes gcc able to optimize it
13  * as well as possible and (b) trying to avoid writing the same thing
14  * over and over again with slight variations and possibly making a
15  * mistake somewhere.
16  */
17 
18 /*
19  * Thanks to James van Artsdalen for a better timing-fix than
20  * the two short jumps: using outb's to a nonexistent port seems
21  * to guarantee better timings even on fast machines.
22  *
23  * On the other hand, I'd like to be sure of a non-existent port:
24  * I feel a bit unsafe about using 0x80 (should be safe, though)
25  *
26  *		Linus
27  */
28 
29  /*
30   *  Bit simplified and optimized by Jan Hubicka
31   *  Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999.
32   *
33   *  isa_memset_io, isa_memcpy_fromio, isa_memcpy_toio added,
34   *  isa_read[wl] and isa_write[wl] fixed
35   *  - Arnaldo Carvalho de Melo <acme@conectiva.com.br>
36   */
37 
38 #define ARCH_HAS_IOREMAP_WC
39 #define ARCH_HAS_IOREMAP_WT
40 
41 #include <linux/string.h>
42 #include <linux/compiler.h>
43 #include <linux/cc_platform.h>
44 #include <asm/page.h>
45 #include <asm/early_ioremap.h>
46 #include <asm/pgtable_types.h>
47 #include <asm/shared/io.h>
48 
49 #define build_mmio_read(name, size, type, reg, barrier) \
50 static inline type name(const volatile void __iomem *addr) \
51 { type ret; asm volatile("mov" size " %1,%0":reg (ret) \
52 :"m" (*(volatile type __force *)addr) barrier); return ret; }
53 
54 #define build_mmio_write(name, size, type, reg, barrier) \
55 static inline void name(type val, volatile void __iomem *addr) \
56 { asm volatile("mov" size " %0,%1": :reg (val), \
57 "m" (*(volatile type __force *)addr) barrier); }
58 
59 build_mmio_read(readb, "b", unsigned char, "=q", :"memory")
60 build_mmio_read(readw, "w", unsigned short, "=r", :"memory")
61 build_mmio_read(readl, "l", unsigned int, "=r", :"memory")
62 
63 build_mmio_read(__readb, "b", unsigned char, "=q", )
64 build_mmio_read(__readw, "w", unsigned short, "=r", )
65 build_mmio_read(__readl, "l", unsigned int, "=r", )
66 
67 build_mmio_write(writeb, "b", unsigned char, "q", :"memory")
68 build_mmio_write(writew, "w", unsigned short, "r", :"memory")
69 build_mmio_write(writel, "l", unsigned int, "r", :"memory")
70 
71 build_mmio_write(__writeb, "b", unsigned char, "q", )
72 build_mmio_write(__writew, "w", unsigned short, "r", )
73 build_mmio_write(__writel, "l", unsigned int, "r", )
74 
75 #define readb readb
76 #define readw readw
77 #define readl readl
78 #define readb_relaxed(a) __readb(a)
79 #define readw_relaxed(a) __readw(a)
80 #define readl_relaxed(a) __readl(a)
81 #define __raw_readb __readb
82 #define __raw_readw __readw
83 #define __raw_readl __readl
84 
85 #define writeb writeb
86 #define writew writew
87 #define writel writel
88 #define writeb_relaxed(v, a) __writeb(v, a)
89 #define writew_relaxed(v, a) __writew(v, a)
90 #define writel_relaxed(v, a) __writel(v, a)
91 #define __raw_writeb __writeb
92 #define __raw_writew __writew
93 #define __raw_writel __writel
94 
95 #ifdef CONFIG_X86_64
96 
97 build_mmio_read(readq, "q", u64, "=r", :"memory")
98 build_mmio_read(__readq, "q", u64, "=r", )
99 build_mmio_write(writeq, "q", u64, "r", :"memory")
100 build_mmio_write(__writeq, "q", u64, "r", )
101 
102 #define readq_relaxed(a)	__readq(a)
103 #define writeq_relaxed(v, a)	__writeq(v, a)
104 
105 #define __raw_readq		__readq
106 #define __raw_writeq		__writeq
107 
108 /* Let people know that we have them */
109 #define readq			readq
110 #define writeq			writeq
111 
112 #endif
113 
114 #define ARCH_HAS_VALID_PHYS_ADDR_RANGE
115 extern int valid_phys_addr_range(phys_addr_t addr, size_t size);
116 extern int valid_mmap_phys_addr_range(unsigned long pfn, size_t size);
117 
118 /**
119  *	virt_to_phys	-	map virtual addresses to physical
120  *	@address: address to remap
121  *
122  *	The returned physical address is the physical (CPU) mapping for
123  *	the memory address given. It is only valid to use this function on
124  *	addresses directly mapped or allocated via kmalloc.
125  *
126  *	This function does not give bus mappings for DMA transfers. In
127  *	almost all conceivable cases a device driver should not be using
128  *	this function
129  */
130 
131 static inline phys_addr_t virt_to_phys(volatile void *address)
132 {
133 	return __pa(address);
134 }
135 #define virt_to_phys virt_to_phys
136 
137 /**
138  *	phys_to_virt	-	map physical address to virtual
139  *	@address: address to remap
140  *
141  *	The returned virtual address is a current CPU mapping for
142  *	the memory address given. It is only valid to use this function on
143  *	addresses that have a kernel mapping
144  *
145  *	This function does not handle bus mappings for DMA transfers. In
146  *	almost all conceivable cases a device driver should not be using
147  *	this function
148  */
149 
150 static inline void *phys_to_virt(phys_addr_t address)
151 {
152 	return __va(address);
153 }
154 #define phys_to_virt phys_to_virt
155 
156 /*
157  * Change "struct page" to physical address.
158  */
159 #define page_to_phys(page)    ((dma_addr_t)page_to_pfn(page) << PAGE_SHIFT)
160 
161 /*
162  * ISA I/O bus memory addresses are 1:1 with the physical address.
163  * However, we truncate the address to unsigned int to avoid undesirable
164  * promotions in legacy drivers.
165  */
166 static inline unsigned int isa_virt_to_bus(volatile void *address)
167 {
168 	return (unsigned int)virt_to_phys(address);
169 }
170 #define isa_bus_to_virt		phys_to_virt
171 
172 /*
173  * The default ioremap() behavior is non-cached; if you need something
174  * else, you probably want one of the following.
175  */
176 extern void __iomem *ioremap_uc(resource_size_t offset, unsigned long size);
177 #define ioremap_uc ioremap_uc
178 extern void __iomem *ioremap_cache(resource_size_t offset, unsigned long size);
179 #define ioremap_cache ioremap_cache
180 extern void __iomem *ioremap_prot(resource_size_t offset, unsigned long size, unsigned long prot_val);
181 #define ioremap_prot ioremap_prot
182 extern void __iomem *ioremap_encrypted(resource_size_t phys_addr, unsigned long size);
183 #define ioremap_encrypted ioremap_encrypted
184 
185 /**
186  * ioremap     -   map bus memory into CPU space
187  * @offset:    bus address of the memory
188  * @size:      size of the resource to map
189  *
190  * ioremap performs a platform specific sequence of operations to
191  * make bus memory CPU accessible via the readb/readw/readl/writeb/
192  * writew/writel functions and the other mmio helpers. The returned
193  * address is not guaranteed to be usable directly as a virtual
194  * address.
195  *
196  * If the area you are trying to map is a PCI BAR you should have a
197  * look at pci_iomap().
198  */
199 void __iomem *ioremap(resource_size_t offset, unsigned long size);
200 #define ioremap ioremap
201 
202 extern void iounmap(volatile void __iomem *addr);
203 #define iounmap iounmap
204 
205 #ifdef __KERNEL__
206 
207 void memcpy_fromio(void *, const volatile void __iomem *, size_t);
208 void memcpy_toio(volatile void __iomem *, const void *, size_t);
209 void memset_io(volatile void __iomem *, int, size_t);
210 
211 #define memcpy_fromio memcpy_fromio
212 #define memcpy_toio memcpy_toio
213 #define memset_io memset_io
214 
215 #include <asm-generic/iomap.h>
216 
217 /*
218  * ISA space is 'always mapped' on a typical x86 system, no need to
219  * explicitly ioremap() it. The fact that the ISA IO space is mapped
220  * to PAGE_OFFSET is pure coincidence - it does not mean ISA values
221  * are physical addresses. The following constant pointer can be
222  * used as the IO-area pointer (it can be iounmapped as well, so the
223  * analogy with PCI is quite large):
224  */
225 #define __ISA_IO_base ((char __iomem *)(PAGE_OFFSET))
226 
227 #endif /* __KERNEL__ */
228 
229 extern void native_io_delay(void);
230 
231 extern int io_delay_type;
232 extern void io_delay_init(void);
233 
234 #if defined(CONFIG_PARAVIRT)
235 #include <asm/paravirt.h>
236 #else
237 
238 static inline void slow_down_io(void)
239 {
240 	native_io_delay();
241 #ifdef REALLY_SLOW_IO
242 	native_io_delay();
243 	native_io_delay();
244 	native_io_delay();
245 #endif
246 }
247 
248 #endif
249 
250 #define BUILDIO(bwl, bw, type)						\
251 static inline void out##bwl##_p(type value, u16 port)			\
252 {									\
253 	out##bwl(value, port);						\
254 	slow_down_io();							\
255 }									\
256 									\
257 static inline type in##bwl##_p(u16 port)				\
258 {									\
259 	type value = in##bwl(port);					\
260 	slow_down_io();							\
261 	return value;							\
262 }									\
263 									\
264 static inline void outs##bwl(u16 port, const void *addr, unsigned long count) \
265 {									\
266 	if (cc_platform_has(CC_ATTR_GUEST_UNROLL_STRING_IO)) {		\
267 		type *value = (type *)addr;				\
268 		while (count) {						\
269 			out##bwl(*value, port);				\
270 			value++;					\
271 			count--;					\
272 		}							\
273 	} else {							\
274 		asm volatile("rep; outs" #bwl				\
275 			     : "+S"(addr), "+c"(count)			\
276 			     : "d"(port) : "memory");			\
277 	}								\
278 }									\
279 									\
280 static inline void ins##bwl(u16 port, void *addr, unsigned long count)	\
281 {									\
282 	if (cc_platform_has(CC_ATTR_GUEST_UNROLL_STRING_IO)) {		\
283 		type *value = (type *)addr;				\
284 		while (count) {						\
285 			*value = in##bwl(port);				\
286 			value++;					\
287 			count--;					\
288 		}							\
289 	} else {							\
290 		asm volatile("rep; ins" #bwl				\
291 			     : "+D"(addr), "+c"(count)			\
292 			     : "d"(port) : "memory");			\
293 	}								\
294 }
295 
296 BUILDIO(b, b, u8)
297 BUILDIO(w, w, u16)
298 BUILDIO(l,  , u32)
299 #undef BUILDIO
300 
301 #define inb_p inb_p
302 #define inw_p inw_p
303 #define inl_p inl_p
304 #define insb insb
305 #define insw insw
306 #define insl insl
307 
308 #define outb_p outb_p
309 #define outw_p outw_p
310 #define outl_p outl_p
311 #define outsb outsb
312 #define outsw outsw
313 #define outsl outsl
314 
315 extern void *xlate_dev_mem_ptr(phys_addr_t phys);
316 extern void unxlate_dev_mem_ptr(phys_addr_t phys, void *addr);
317 
318 #define xlate_dev_mem_ptr xlate_dev_mem_ptr
319 #define unxlate_dev_mem_ptr unxlate_dev_mem_ptr
320 
321 extern int ioremap_change_attr(unsigned long vaddr, unsigned long size,
322 				enum page_cache_mode pcm);
323 extern void __iomem *ioremap_wc(resource_size_t offset, unsigned long size);
324 #define ioremap_wc ioremap_wc
325 extern void __iomem *ioremap_wt(resource_size_t offset, unsigned long size);
326 #define ioremap_wt ioremap_wt
327 
328 extern bool is_early_ioremap_ptep(pte_t *ptep);
329 
330 #define IO_SPACE_LIMIT 0xffff
331 
332 #include <asm-generic/io.h>
333 #undef PCI_IOBASE
334 
335 #ifdef CONFIG_MTRR
336 extern int __must_check arch_phys_wc_index(int handle);
337 #define arch_phys_wc_index arch_phys_wc_index
338 
339 extern int __must_check arch_phys_wc_add(unsigned long base,
340 					 unsigned long size);
341 extern void arch_phys_wc_del(int handle);
342 #define arch_phys_wc_add arch_phys_wc_add
343 #endif
344 
345 #ifdef CONFIG_X86_PAT
346 extern int arch_io_reserve_memtype_wc(resource_size_t start, resource_size_t size);
347 extern void arch_io_free_memtype_wc(resource_size_t start, resource_size_t size);
348 #define arch_io_reserve_memtype_wc arch_io_reserve_memtype_wc
349 #endif
350 
351 #ifdef CONFIG_AMD_MEM_ENCRYPT
352 extern bool arch_memremap_can_ram_remap(resource_size_t offset,
353 					unsigned long size,
354 					unsigned long flags);
355 #define arch_memremap_can_ram_remap arch_memremap_can_ram_remap
356 
357 extern bool phys_mem_access_encrypted(unsigned long phys_addr,
358 				      unsigned long size);
359 #else
360 static inline bool phys_mem_access_encrypted(unsigned long phys_addr,
361 					     unsigned long size)
362 {
363 	return true;
364 }
365 #endif
366 
367 /**
368  * iosubmit_cmds512 - copy data to single MMIO location, in 512-bit units
369  * @dst: destination, in MMIO space (must be 512-bit aligned)
370  * @src: source
371  * @count: number of 512 bits quantities to submit
372  *
373  * Submit data from kernel space to MMIO space, in units of 512 bits at a
374  * time.  Order of access is not guaranteed, nor is a memory barrier
375  * performed afterwards.
376  *
377  * Warning: Do not use this helper unless your driver has checked that the CPU
378  * instruction is supported on the platform.
379  */
380 static inline void iosubmit_cmds512(void __iomem *dst, const void *src,
381 				    size_t count)
382 {
383 	const u8 *from = src;
384 	const u8 *end = from + count * 64;
385 
386 	while (from < end) {
387 		movdir64b(dst, from);
388 		from += 64;
389 	}
390 }
391 
392 #endif /* _ASM_X86_IO_H */
393