xref: /kernel/linux/linux-5.10/arch/x86/include/asm/io.h (revision 8c2ecf20)
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 <asm/page.h>
44#include <asm/early_ioremap.h>
45#include <asm/pgtable_types.h>
46
47#define build_mmio_read(name, size, type, reg, barrier) \
48static inline type name(const volatile void __iomem *addr) \
49{ type ret; asm volatile("mov" size " %1,%0":reg (ret) \
50:"m" (*(volatile type __force *)addr) barrier); return ret; }
51
52#define build_mmio_write(name, size, type, reg, barrier) \
53static inline void name(type val, volatile void __iomem *addr) \
54{ asm volatile("mov" size " %0,%1": :reg (val), \
55"m" (*(volatile type __force *)addr) barrier); }
56
57build_mmio_read(readb, "b", unsigned char, "=q", :"memory")
58build_mmio_read(readw, "w", unsigned short, "=r", :"memory")
59build_mmio_read(readl, "l", unsigned int, "=r", :"memory")
60
61build_mmio_read(__readb, "b", unsigned char, "=q", )
62build_mmio_read(__readw, "w", unsigned short, "=r", )
63build_mmio_read(__readl, "l", unsigned int, "=r", )
64
65build_mmio_write(writeb, "b", unsigned char, "q", :"memory")
66build_mmio_write(writew, "w", unsigned short, "r", :"memory")
67build_mmio_write(writel, "l", unsigned int, "r", :"memory")
68
69build_mmio_write(__writeb, "b", unsigned char, "q", )
70build_mmio_write(__writew, "w", unsigned short, "r", )
71build_mmio_write(__writel, "l", unsigned int, "r", )
72
73#define readb readb
74#define readw readw
75#define readl readl
76#define readb_relaxed(a) __readb(a)
77#define readw_relaxed(a) __readw(a)
78#define readl_relaxed(a) __readl(a)
79#define __raw_readb __readb
80#define __raw_readw __readw
81#define __raw_readl __readl
82
83#define writeb writeb
84#define writew writew
85#define writel writel
86#define writeb_relaxed(v, a) __writeb(v, a)
87#define writew_relaxed(v, a) __writew(v, a)
88#define writel_relaxed(v, a) __writel(v, a)
89#define __raw_writeb __writeb
90#define __raw_writew __writew
91#define __raw_writel __writel
92
93#ifdef CONFIG_X86_64
94
95build_mmio_read(readq, "q", u64, "=r", :"memory")
96build_mmio_read(__readq, "q", u64, "=r", )
97build_mmio_write(writeq, "q", u64, "r", :"memory")
98build_mmio_write(__writeq, "q", u64, "r", )
99
100#define readq_relaxed(a)	__readq(a)
101#define writeq_relaxed(v, a)	__writeq(v, a)
102
103#define __raw_readq		__readq
104#define __raw_writeq		__writeq
105
106/* Let people know that we have them */
107#define readq			readq
108#define writeq			writeq
109
110#endif
111
112#define ARCH_HAS_VALID_PHYS_ADDR_RANGE
113extern int valid_phys_addr_range(phys_addr_t addr, size_t size);
114extern int valid_mmap_phys_addr_range(unsigned long pfn, size_t size);
115
116/**
117 *	virt_to_phys	-	map virtual addresses to physical
118 *	@address: address to remap
119 *
120 *	The returned physical address is the physical (CPU) mapping for
121 *	the memory address given. It is only valid to use this function on
122 *	addresses directly mapped or allocated via kmalloc.
123 *
124 *	This function does not give bus mappings for DMA transfers. In
125 *	almost all conceivable cases a device driver should not be using
126 *	this function
127 */
128
129static inline phys_addr_t virt_to_phys(volatile void *address)
130{
131	return __pa(address);
132}
133#define virt_to_phys virt_to_phys
134
135/**
136 *	phys_to_virt	-	map physical address to virtual
137 *	@address: address to remap
138 *
139 *	The returned virtual address is a current CPU mapping for
140 *	the memory address given. It is only valid to use this function on
141 *	addresses that have a kernel mapping
142 *
143 *	This function does not handle bus mappings for DMA transfers. In
144 *	almost all conceivable cases a device driver should not be using
145 *	this function
146 */
147
148static inline void *phys_to_virt(phys_addr_t address)
149{
150	return __va(address);
151}
152#define phys_to_virt phys_to_virt
153
154/*
155 * Change "struct page" to physical address.
156 */
157#define page_to_phys(page)    ((dma_addr_t)page_to_pfn(page) << PAGE_SHIFT)
158
159/*
160 * ISA I/O bus memory addresses are 1:1 with the physical address.
161 * However, we truncate the address to unsigned int to avoid undesirable
162 * promitions in legacy drivers.
163 */
164static inline unsigned int isa_virt_to_bus(volatile void *address)
165{
166	return (unsigned int)virt_to_phys(address);
167}
168#define isa_bus_to_virt		phys_to_virt
169
170/*
171 * However PCI ones are not necessarily 1:1 and therefore these interfaces
172 * are forbidden in portable PCI drivers.
173 *
174 * Allow them on x86 for legacy drivers, though.
175 */
176#define virt_to_bus virt_to_phys
177#define bus_to_virt phys_to_virt
178
179/*
180 * The default ioremap() behavior is non-cached; if you need something
181 * else, you probably want one of the following.
182 */
183extern void __iomem *ioremap_uc(resource_size_t offset, unsigned long size);
184#define ioremap_uc ioremap_uc
185extern void __iomem *ioremap_cache(resource_size_t offset, unsigned long size);
186#define ioremap_cache ioremap_cache
187extern void __iomem *ioremap_prot(resource_size_t offset, unsigned long size, unsigned long prot_val);
188#define ioremap_prot ioremap_prot
189extern void __iomem *ioremap_encrypted(resource_size_t phys_addr, unsigned long size);
190#define ioremap_encrypted ioremap_encrypted
191
192/**
193 * ioremap     -   map bus memory into CPU space
194 * @offset:    bus address of the memory
195 * @size:      size of the resource to map
196 *
197 * ioremap performs a platform specific sequence of operations to
198 * make bus memory CPU accessible via the readb/readw/readl/writeb/
199 * writew/writel functions and the other mmio helpers. The returned
200 * address is not guaranteed to be usable directly as a virtual
201 * address.
202 *
203 * If the area you are trying to map is a PCI BAR you should have a
204 * look at pci_iomap().
205 */
206void __iomem *ioremap(resource_size_t offset, unsigned long size);
207#define ioremap ioremap
208
209extern void iounmap(volatile void __iomem *addr);
210#define iounmap iounmap
211
212extern void set_iounmap_nonlazy(void);
213
214#ifdef __KERNEL__
215
216void memcpy_fromio(void *, const volatile void __iomem *, size_t);
217void memcpy_toio(volatile void __iomem *, const void *, size_t);
218void memset_io(volatile void __iomem *, int, size_t);
219
220#define memcpy_fromio memcpy_fromio
221#define memcpy_toio memcpy_toio
222#define memset_io memset_io
223
224#include <asm-generic/iomap.h>
225
226/*
227 * ISA space is 'always mapped' on a typical x86 system, no need to
228 * explicitly ioremap() it. The fact that the ISA IO space is mapped
229 * to PAGE_OFFSET is pure coincidence - it does not mean ISA values
230 * are physical addresses. The following constant pointer can be
231 * used as the IO-area pointer (it can be iounmapped as well, so the
232 * analogy with PCI is quite large):
233 */
234#define __ISA_IO_base ((char __iomem *)(PAGE_OFFSET))
235
236#endif /* __KERNEL__ */
237
238extern void native_io_delay(void);
239
240extern int io_delay_type;
241extern void io_delay_init(void);
242
243#if defined(CONFIG_PARAVIRT)
244#include <asm/paravirt.h>
245#else
246
247static inline void slow_down_io(void)
248{
249	native_io_delay();
250#ifdef REALLY_SLOW_IO
251	native_io_delay();
252	native_io_delay();
253	native_io_delay();
254#endif
255}
256
257#endif
258
259#ifdef CONFIG_AMD_MEM_ENCRYPT
260#include <linux/jump_label.h>
261
262extern struct static_key_false sev_enable_key;
263static inline bool sev_key_active(void)
264{
265	return static_branch_unlikely(&sev_enable_key);
266}
267
268#else /* !CONFIG_AMD_MEM_ENCRYPT */
269
270static inline bool sev_key_active(void) { return false; }
271
272#endif /* CONFIG_AMD_MEM_ENCRYPT */
273
274#define BUILDIO(bwl, bw, type)						\
275static inline void out##bwl(unsigned type value, int port)		\
276{									\
277	asm volatile("out" #bwl " %" #bw "0, %w1"			\
278		     : : "a"(value), "Nd"(port));			\
279}									\
280									\
281static inline unsigned type in##bwl(int port)				\
282{									\
283	unsigned type value;						\
284	asm volatile("in" #bwl " %w1, %" #bw "0"			\
285		     : "=a"(value) : "Nd"(port));			\
286	return value;							\
287}									\
288									\
289static inline void out##bwl##_p(unsigned type value, int port)		\
290{									\
291	out##bwl(value, port);						\
292	slow_down_io();							\
293}									\
294									\
295static inline unsigned type in##bwl##_p(int port)			\
296{									\
297	unsigned type value = in##bwl(port);				\
298	slow_down_io();							\
299	return value;							\
300}									\
301									\
302static inline void outs##bwl(int port, const void *addr, unsigned long count) \
303{									\
304	if (sev_key_active()) {						\
305		unsigned type *value = (unsigned type *)addr;		\
306		while (count) {						\
307			out##bwl(*value, port);				\
308			value++;					\
309			count--;					\
310		}							\
311	} else {							\
312		asm volatile("rep; outs" #bwl				\
313			     : "+S"(addr), "+c"(count)			\
314			     : "d"(port) : "memory");			\
315	}								\
316}									\
317									\
318static inline void ins##bwl(int port, void *addr, unsigned long count)	\
319{									\
320	if (sev_key_active()) {						\
321		unsigned type *value = (unsigned type *)addr;		\
322		while (count) {						\
323			*value = in##bwl(port);				\
324			value++;					\
325			count--;					\
326		}							\
327	} else {							\
328		asm volatile("rep; ins" #bwl				\
329			     : "+D"(addr), "+c"(count)			\
330			     : "d"(port) : "memory");			\
331	}								\
332}
333
334BUILDIO(b, b, char)
335BUILDIO(w, w, short)
336BUILDIO(l, , int)
337
338#define inb inb
339#define inw inw
340#define inl inl
341#define inb_p inb_p
342#define inw_p inw_p
343#define inl_p inl_p
344#define insb insb
345#define insw insw
346#define insl insl
347
348#define outb outb
349#define outw outw
350#define outl outl
351#define outb_p outb_p
352#define outw_p outw_p
353#define outl_p outl_p
354#define outsb outsb
355#define outsw outsw
356#define outsl outsl
357
358extern void *xlate_dev_mem_ptr(phys_addr_t phys);
359extern void unxlate_dev_mem_ptr(phys_addr_t phys, void *addr);
360
361#define xlate_dev_mem_ptr xlate_dev_mem_ptr
362#define unxlate_dev_mem_ptr unxlate_dev_mem_ptr
363
364extern int ioremap_change_attr(unsigned long vaddr, unsigned long size,
365				enum page_cache_mode pcm);
366extern void __iomem *ioremap_wc(resource_size_t offset, unsigned long size);
367#define ioremap_wc ioremap_wc
368extern void __iomem *ioremap_wt(resource_size_t offset, unsigned long size);
369#define ioremap_wt ioremap_wt
370
371extern bool is_early_ioremap_ptep(pte_t *ptep);
372
373#define IO_SPACE_LIMIT 0xffff
374
375#include <asm-generic/io.h>
376#undef PCI_IOBASE
377
378#ifdef CONFIG_MTRR
379extern int __must_check arch_phys_wc_index(int handle);
380#define arch_phys_wc_index arch_phys_wc_index
381
382extern int __must_check arch_phys_wc_add(unsigned long base,
383					 unsigned long size);
384extern void arch_phys_wc_del(int handle);
385#define arch_phys_wc_add arch_phys_wc_add
386#endif
387
388#ifdef CONFIG_X86_PAT
389extern int arch_io_reserve_memtype_wc(resource_size_t start, resource_size_t size);
390extern void arch_io_free_memtype_wc(resource_size_t start, resource_size_t size);
391#define arch_io_reserve_memtype_wc arch_io_reserve_memtype_wc
392#endif
393
394extern bool arch_memremap_can_ram_remap(resource_size_t offset,
395					unsigned long size,
396					unsigned long flags);
397#define arch_memremap_can_ram_remap arch_memremap_can_ram_remap
398
399extern bool phys_mem_access_encrypted(unsigned long phys_addr,
400				      unsigned long size);
401
402/**
403 * iosubmit_cmds512 - copy data to single MMIO location, in 512-bit units
404 * @dst: destination, in MMIO space (must be 512-bit aligned)
405 * @src: source
406 * @count: number of 512 bits quantities to submit
407 *
408 * Submit data from kernel space to MMIO space, in units of 512 bits at a
409 * time.  Order of access is not guaranteed, nor is a memory barrier
410 * performed afterwards.
411 *
412 * Warning: Do not use this helper unless your driver has checked that the CPU
413 * instruction is supported on the platform.
414 */
415static inline void iosubmit_cmds512(void __iomem *dst, const void *src,
416				    size_t count)
417{
418	const u8 *from = src;
419	const u8 *end = from + count * 64;
420
421	while (from < end) {
422		movdir64b(dst, from);
423		from += 64;
424	}
425}
426
427#endif /* _ASM_X86_IO_H */
428