xref: /openbmc/linux/arch/x86/include/asm/io.h (revision 1cac4f26)
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) \
48 static 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) \
53 static 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 
57 build_mmio_read(readb, "b", unsigned char, "=q", :"memory")
58 build_mmio_read(readw, "w", unsigned short, "=r", :"memory")
59 build_mmio_read(readl, "l", unsigned int, "=r", :"memory")
60 
61 build_mmio_read(__readb, "b", unsigned char, "=q", )
62 build_mmio_read(__readw, "w", unsigned short, "=r", )
63 build_mmio_read(__readl, "l", unsigned int, "=r", )
64 
65 build_mmio_write(writeb, "b", unsigned char, "q", :"memory")
66 build_mmio_write(writew, "w", unsigned short, "r", :"memory")
67 build_mmio_write(writel, "l", unsigned int, "r", :"memory")
68 
69 build_mmio_write(__writeb, "b", unsigned char, "q", )
70 build_mmio_write(__writew, "w", unsigned short, "r", )
71 build_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 #define mmiowb() barrier()
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  * promitions 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_page_to_bus(page)	((unsigned int)page_to_phys(page))
171 #define isa_bus_to_virt		phys_to_virt
172 
173 /*
174  * However PCI ones are not necessarily 1:1 and therefore these interfaces
175  * are forbidden in portable PCI drivers.
176  *
177  * Allow them on x86 for legacy drivers, though.
178  */
179 #define virt_to_bus virt_to_phys
180 #define bus_to_virt phys_to_virt
181 
182 /*
183  * The default ioremap() behavior is non-cached; if you need something
184  * else, you probably want one of the following.
185  */
186 extern void __iomem *ioremap_nocache(resource_size_t offset, unsigned long size);
187 #define ioremap_nocache ioremap_nocache
188 extern void __iomem *ioremap_uc(resource_size_t offset, unsigned long size);
189 #define ioremap_uc ioremap_uc
190 extern void __iomem *ioremap_cache(resource_size_t offset, unsigned long size);
191 #define ioremap_cache ioremap_cache
192 extern void __iomem *ioremap_prot(resource_size_t offset, unsigned long size, unsigned long prot_val);
193 #define ioremap_prot ioremap_prot
194 extern void __iomem *ioremap_encrypted(resource_size_t phys_addr, unsigned long size);
195 #define ioremap_encrypted ioremap_encrypted
196 
197 /**
198  * ioremap     -   map bus memory into CPU space
199  * @offset:    bus address of the memory
200  * @size:      size of the resource to map
201  *
202  * ioremap performs a platform specific sequence of operations to
203  * make bus memory CPU accessible via the readb/readw/readl/writeb/
204  * writew/writel functions and the other mmio helpers. The returned
205  * address is not guaranteed to be usable directly as a virtual
206  * address.
207  *
208  * If the area you are trying to map is a PCI BAR you should have a
209  * look at pci_iomap().
210  */
211 static inline void __iomem *ioremap(resource_size_t offset, unsigned long size)
212 {
213 	return ioremap_nocache(offset, size);
214 }
215 #define ioremap ioremap
216 
217 extern void iounmap(volatile void __iomem *addr);
218 #define iounmap iounmap
219 
220 extern void set_iounmap_nonlazy(void);
221 
222 #ifdef __KERNEL__
223 
224 void memcpy_fromio(void *, const volatile void __iomem *, size_t);
225 void memcpy_toio(volatile void __iomem *, const void *, size_t);
226 void memset_io(volatile void __iomem *, int, size_t);
227 
228 #define memcpy_fromio memcpy_fromio
229 #define memcpy_toio memcpy_toio
230 #define memset_io memset_io
231 
232 #include <asm-generic/iomap.h>
233 
234 /*
235  * ISA space is 'always mapped' on a typical x86 system, no need to
236  * explicitly ioremap() it. The fact that the ISA IO space is mapped
237  * to PAGE_OFFSET is pure coincidence - it does not mean ISA values
238  * are physical addresses. The following constant pointer can be
239  * used as the IO-area pointer (it can be iounmapped as well, so the
240  * analogy with PCI is quite large):
241  */
242 #define __ISA_IO_base ((char __iomem *)(PAGE_OFFSET))
243 
244 #endif /* __KERNEL__ */
245 
246 extern void native_io_delay(void);
247 
248 extern int io_delay_type;
249 extern void io_delay_init(void);
250 
251 #if defined(CONFIG_PARAVIRT)
252 #include <asm/paravirt.h>
253 #else
254 
255 static inline void slow_down_io(void)
256 {
257 	native_io_delay();
258 #ifdef REALLY_SLOW_IO
259 	native_io_delay();
260 	native_io_delay();
261 	native_io_delay();
262 #endif
263 }
264 
265 #endif
266 
267 #ifdef CONFIG_AMD_MEM_ENCRYPT
268 #include <linux/jump_label.h>
269 
270 extern struct static_key_false sev_enable_key;
271 static inline bool sev_key_active(void)
272 {
273 	return static_branch_unlikely(&sev_enable_key);
274 }
275 
276 #else /* !CONFIG_AMD_MEM_ENCRYPT */
277 
278 static inline bool sev_key_active(void) { return false; }
279 
280 #endif /* CONFIG_AMD_MEM_ENCRYPT */
281 
282 #define BUILDIO(bwl, bw, type)						\
283 static inline void out##bwl(unsigned type value, int port)		\
284 {									\
285 	asm volatile("out" #bwl " %" #bw "0, %w1"			\
286 		     : : "a"(value), "Nd"(port));			\
287 }									\
288 									\
289 static inline unsigned type in##bwl(int port)				\
290 {									\
291 	unsigned type value;						\
292 	asm volatile("in" #bwl " %w1, %" #bw "0"			\
293 		     : "=a"(value) : "Nd"(port));			\
294 	return value;							\
295 }									\
296 									\
297 static inline void out##bwl##_p(unsigned type value, int port)		\
298 {									\
299 	out##bwl(value, port);						\
300 	slow_down_io();							\
301 }									\
302 									\
303 static inline unsigned type in##bwl##_p(int port)			\
304 {									\
305 	unsigned type value = in##bwl(port);				\
306 	slow_down_io();							\
307 	return value;							\
308 }									\
309 									\
310 static inline void outs##bwl(int port, const void *addr, unsigned long count) \
311 {									\
312 	if (sev_key_active()) {						\
313 		unsigned type *value = (unsigned type *)addr;		\
314 		while (count) {						\
315 			out##bwl(*value, port);				\
316 			value++;					\
317 			count--;					\
318 		}							\
319 	} else {							\
320 		asm volatile("rep; outs" #bwl				\
321 			     : "+S"(addr), "+c"(count)			\
322 			     : "d"(port) : "memory");			\
323 	}								\
324 }									\
325 									\
326 static inline void ins##bwl(int port, void *addr, unsigned long count)	\
327 {									\
328 	if (sev_key_active()) {						\
329 		unsigned type *value = (unsigned type *)addr;		\
330 		while (count) {						\
331 			*value = in##bwl(port);				\
332 			value++;					\
333 			count--;					\
334 		}							\
335 	} else {							\
336 		asm volatile("rep; ins" #bwl				\
337 			     : "+D"(addr), "+c"(count)			\
338 			     : "d"(port) : "memory");			\
339 	}								\
340 }
341 
342 BUILDIO(b, b, char)
343 BUILDIO(w, w, short)
344 BUILDIO(l, , int)
345 
346 #define inb inb
347 #define inw inw
348 #define inl inl
349 #define inb_p inb_p
350 #define inw_p inw_p
351 #define inl_p inl_p
352 #define insb insb
353 #define insw insw
354 #define insl insl
355 
356 #define outb outb
357 #define outw outw
358 #define outl outl
359 #define outb_p outb_p
360 #define outw_p outw_p
361 #define outl_p outl_p
362 #define outsb outsb
363 #define outsw outsw
364 #define outsl outsl
365 
366 extern void *xlate_dev_mem_ptr(phys_addr_t phys);
367 extern void unxlate_dev_mem_ptr(phys_addr_t phys, void *addr);
368 
369 #define xlate_dev_mem_ptr xlate_dev_mem_ptr
370 #define unxlate_dev_mem_ptr unxlate_dev_mem_ptr
371 
372 extern int ioremap_change_attr(unsigned long vaddr, unsigned long size,
373 				enum page_cache_mode pcm);
374 extern void __iomem *ioremap_wc(resource_size_t offset, unsigned long size);
375 #define ioremap_wc ioremap_wc
376 extern void __iomem *ioremap_wt(resource_size_t offset, unsigned long size);
377 #define ioremap_wt ioremap_wt
378 
379 extern bool is_early_ioremap_ptep(pte_t *ptep);
380 
381 #define IO_SPACE_LIMIT 0xffff
382 
383 #include <asm-generic/io.h>
384 #undef PCI_IOBASE
385 
386 #ifdef CONFIG_MTRR
387 extern int __must_check arch_phys_wc_index(int handle);
388 #define arch_phys_wc_index arch_phys_wc_index
389 
390 extern int __must_check arch_phys_wc_add(unsigned long base,
391 					 unsigned long size);
392 extern void arch_phys_wc_del(int handle);
393 #define arch_phys_wc_add arch_phys_wc_add
394 #endif
395 
396 #ifdef CONFIG_X86_PAT
397 extern int arch_io_reserve_memtype_wc(resource_size_t start, resource_size_t size);
398 extern void arch_io_free_memtype_wc(resource_size_t start, resource_size_t size);
399 #define arch_io_reserve_memtype_wc arch_io_reserve_memtype_wc
400 #endif
401 
402 extern bool arch_memremap_can_ram_remap(resource_size_t offset,
403 					unsigned long size,
404 					unsigned long flags);
405 #define arch_memremap_can_ram_remap arch_memremap_can_ram_remap
406 
407 extern bool phys_mem_access_encrypted(unsigned long phys_addr,
408 				      unsigned long size);
409 
410 #endif /* _ASM_X86_IO_H */
411