arch/x86/include/asm/io.h

   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", unsigned long, "=r", :"memory")
  98 build_mmio_read(__readq, "q", unsigned long, "=r", )
  99 build_mmio_write(writeq, "q", unsigned long, "r", :"memory")
 100 build_mmio_write(__writeq, "q", unsigned long, "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 /**
 115  *      virt_to_phys    -       map virtual addresses to physical
 116  *      @address: address to remap
 117  *
 118  *      The returned physical address is the physical (CPU) mapping for
 119  *      the memory address given. It is only valid to use this function on
 120  *      addresses directly mapped or allocated via kmalloc.
 121  *
 122  *      This function does not give bus mappings for DMA transfers. In
 123  *      almost all conceivable cases a device driver should not be using
 124  *      this function
 125  */
 126
 127 static inline phys_addr_t virt_to_phys(volatile void *address)
 128 {
 129         return __pa(address);
 130 }
 131 #define virt_to_phys virt_to_phys
 132
 133 /**
 134  *      phys_to_virt    -       map physical address to virtual
 135  *      @address: address to remap
 136  *
 137  *      The returned virtual address is a current CPU mapping for
 138  *      the memory address given. It is only valid to use this function on
 139  *      addresses that have a kernel mapping
 140  *
 141  *      This function does not handle bus mappings for DMA transfers. In
 142  *      almost all conceivable cases a device driver should not be using
 143  *      this function
 144  */
 145
 146 static inline void *phys_to_virt(phys_addr_t address)
 147 {
 148         return __va(address);
 149 }
 150 #define phys_to_virt phys_to_virt
 151
 152 /*
 153  * Change "struct page" to physical address.
 154  */
 155 #define page_to_phys(page)    ((dma_addr_t)page_to_pfn(page) << PAGE_SHIFT)
 156
 157 /*
 158  * ISA I/O bus memory addresses are 1:1 with the physical address.
 159  * However, we truncate the address to unsigned int to avoid undesirable
 160  * promitions in legacy drivers.
 161  */
 162 static inline unsigned int isa_virt_to_bus(volatile void *address)
 163 {
 164         return (unsigned int)virt_to_phys(address);
 165 }
 166 #define isa_page_to_bus(page)   ((unsigned int)page_to_phys(page))
 167 #define isa_bus_to_virt         phys_to_virt
 168
 169 /*
 170  * However PCI ones are not necessarily 1:1 and therefore these interfaces
 171  * are forbidden in portable PCI drivers.
 172  *
 173  * Allow them on x86 for legacy drivers, though.
 174  */
 175 #define virt_to_bus virt_to_phys
 176 #define bus_to_virt phys_to_virt
 177
 178 /*
 179  * The default ioremap() behavior is non-cached; if you need something
 180  * else, you probably want one of the following.
 181  */
 182 extern void __iomem *ioremap_nocache(resource_size_t offset, unsigned long size);
 183 #define ioremap_nocache ioremap_nocache
 184 extern void __iomem *ioremap_uc(resource_size_t offset, unsigned long size);
 185 #define ioremap_uc ioremap_uc
 186
 187 extern void __iomem *ioremap_cache(resource_size_t offset, unsigned long size);
 188 #define ioremap_cache ioremap_cache
 189 extern void __iomem *ioremap_prot(resource_size_t offset, unsigned long size, unsigned long prot_val);
 190 #define ioremap_prot ioremap_prot
 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  */
 206 static inline void __iomem *ioremap(resource_size_t offset, unsigned long size)
 207 {
 208         return ioremap_nocache(offset, size);
 209 }
 210 #define ioremap ioremap
 211
 212 extern void iounmap(volatile void __iomem *addr);
 213 #define iounmap iounmap
 214
 215 extern void set_iounmap_nonlazy(void);
 216
 217 #ifdef __KERNEL__
 218
 219 #include <asm-generic/iomap.h>
 220
 221 /*
 222  * ISA space is 'always mapped' on a typical x86 system, no need to
 223  * explicitly ioremap() it. The fact that the ISA IO space is mapped
 224  * to PAGE_OFFSET is pure coincidence - it does not mean ISA values
 225  * are physical addresses. The following constant pointer can be
 226  * used as the IO-area pointer (it can be iounmapped as well, so the
 227  * analogy with PCI is quite large):
 228  */
 229 #define __ISA_IO_base ((char __iomem *)(PAGE_OFFSET))
 230
 231 /*
 232  *      Cache management
 233  *
 234  *      This needed for two cases
 235  *      1. Out of order aware processors
 236  *      2. Accidentally out of order processors (PPro errata #51)
 237  */
 238
 239 static inline void flush_write_buffers(void)
 240 {
 241 #if defined(CONFIG_X86_PPRO_FENCE)
 242         asm volatile("lock; addl $0,0(%%esp)": : :"memory");
 243 #endif
 244 }
 245
 246 #endif /* __KERNEL__ */
 247
 248 extern void native_io_delay(void);
 249
 250 extern int io_delay_type;
 251 extern void io_delay_init(void);
 252
 253 #if defined(CONFIG_PARAVIRT)
 254 #include <asm/paravirt.h>
 255 #else
 256
 257 static inline void slow_down_io(void)
 258 {
 259         native_io_delay();
 260 #ifdef REALLY_SLOW_IO
 261         native_io_delay();
 262         native_io_delay();
 263         native_io_delay();
 264 #endif
 265 }
 266
 267 #endif
 268
 269 #ifdef CONFIG_AMD_MEM_ENCRYPT
 270 #include <linux/jump_label.h>
 271
 272 extern struct static_key_false sev_enable_key;
 273 static inline bool sev_key_active(void)
 274 {
 275         return static_branch_unlikely(&sev_enable_key);
 276 }
 277
 278 #else /* !CONFIG_AMD_MEM_ENCRYPT */
 279
 280 static inline bool sev_key_active(void) { return false; }
 281
 282 #endif /* CONFIG_AMD_MEM_ENCRYPT */
 283
 284 #define BUILDIO(bwl, bw, type)                                          \
 285 static inline void out##bwl(unsigned type value, int port)              \
 286 {                                                                       \
 287         asm volatile("out" #bwl " %" #bw "0, %w1"                       \
 288                      : : "a"(value), "Nd"(port));                       \
 289 }                                                                       \
 290                                                                         \
 291 static inline unsigned type in##bwl(int port)                           \
 292 {                                                                       \
 293         unsigned type value;                                            \
 294         asm volatile("in" #bwl " %w1, %" #bw "0"                        \
 295                      : "=a"(value) : "Nd"(port));                       \
 296         return value;                                                   \
 297 }                                                                       \
 298                                                                         \
 299 static inline void out##bwl##_p(unsigned type value, int port)          \
 300 {                                                                       \
 301         out##bwl(value, port);                                          \
 302         slow_down_io();                                                 \
 303 }                                                                       \
 304                                                                         \
 305 static inline unsigned type in##bwl##_p(int port)                       \
 306 {                                                                       \
 307         unsigned type value = in##bwl(port);                            \
 308         slow_down_io();                                                 \
 309         return value;                                                   \
 310 }                                                                       \
 311                                                                         \
 312 static inline void outs##bwl(int port, const void *addr, unsigned long count) \
 313 {                                                                       \
 314         if (sev_key_active()) {                                         \
 315                 unsigned type *value = (unsigned type *)addr;           \
 316                 while (count) {                                         \
 317                         out##bwl(*value, port);                         \
 318                         value++;                                        \
 319                         count--;                                        \
 320                 }                                                       \
 321         } else {                                                        \
 322                 asm volatile("rep; outs" #bwl                           \
 323                              : "+S"(addr), "+c"(count)                  \
 324                              : "d"(port) : "memory");                   \
 325         }                                                               \
 326 }                                                                       \
 327                                                                         \
 328 static inline void ins##bwl(int port, void *addr, unsigned long count)  \
 329 {                                                                       \
 330         if (sev_key_active()) {                                         \
 331                 unsigned type *value = (unsigned type *)addr;           \
 332                 while (count) {                                         \
 333                         *value = in##bwl(port);                         \
 334                         value++;                                        \
 335                         count--;                                        \
 336                 }                                                       \
 337         } else {                                                        \
 338                 asm volatile("rep; ins" #bwl                            \
 339                              : "+D"(addr), "+c"(count)                  \
 340                              : "d"(port) : "memory");                   \
 341         }                                                               \
 342 }
 343
 344 BUILDIO(b, b, char)
 345 BUILDIO(w, w, short)
 346 BUILDIO(l, , int)
 347
 348 #define inb inb
 349 #define inw inw
 350 #define inl inl
 351 #define inb_p inb_p
 352 #define inw_p inw_p
 353 #define inl_p inl_p
 354 #define insb insb
 355 #define insw insw
 356 #define insl insl
 357
 358 #define outb outb
 359 #define outw outw
 360 #define outl outl
 361 #define outb_p outb_p
 362 #define outw_p outw_p
 363 #define outl_p outl_p
 364 #define outsb outsb
 365 #define outsw outsw
 366 #define outsl outsl
 367
 368 extern void *xlate_dev_mem_ptr(phys_addr_t phys);
 369 extern void unxlate_dev_mem_ptr(phys_addr_t phys, void *addr);
 370
 371 #define xlate_dev_mem_ptr xlate_dev_mem_ptr
 372 #define unxlate_dev_mem_ptr unxlate_dev_mem_ptr
 373
 374 extern int ioremap_change_attr(unsigned long vaddr, unsigned long size,
 375                                 enum page_cache_mode pcm);
 376 extern void __iomem *ioremap_wc(resource_size_t offset, unsigned long size);
 377 #define ioremap_wc ioremap_wc
 378 extern void __iomem *ioremap_wt(resource_size_t offset, unsigned long size);
 379 #define ioremap_wt ioremap_wt
 380
 381 extern bool is_early_ioremap_ptep(pte_t *ptep);
 382
 383 #ifdef CONFIG_XEN
 384 #include <xen/xen.h>
 385 struct bio_vec;
 386
 387 extern bool xen_biovec_phys_mergeable(const struct bio_vec *vec1,
 388                                       const struct bio_vec *vec2);
 389
 390 #define BIOVEC_PHYS_MERGEABLE(vec1, vec2)                               \
 391         (__BIOVEC_PHYS_MERGEABLE(vec1, vec2) &&                         \
 392          (!xen_domain() || xen_biovec_phys_mergeable(vec1, vec2)))
 393 #endif  /* CONFIG_XEN */
 394
 395 #define IO_SPACE_LIMIT 0xffff
 396
 397 #include <asm-generic/io.h>
 398 #undef PCI_IOBASE
 399
 400 #ifdef CONFIG_MTRR
 401 extern int __must_check arch_phys_wc_index(int handle);
 402 #define arch_phys_wc_index arch_phys_wc_index
 403
 404 extern int __must_check arch_phys_wc_add(unsigned long base,
 405                                          unsigned long size);
 406 extern void arch_phys_wc_del(int handle);
 407 #define arch_phys_wc_add arch_phys_wc_add
 408 #endif
 409
 410 #ifdef CONFIG_X86_PAT
 411 extern int arch_io_reserve_memtype_wc(resource_size_t start, resource_size_t size);
 412 extern void arch_io_free_memtype_wc(resource_size_t start, resource_size_t size);
 413 #define arch_io_reserve_memtype_wc arch_io_reserve_memtype_wc
 414 #endif
 415
 416 extern bool arch_memremap_can_ram_remap(resource_size_t offset,
 417                                         unsigned long size,
 418                                         unsigned long flags);
 419 #define arch_memremap_can_ram_remap arch_memremap_can_ram_remap
 420
 421 extern bool phys_mem_access_encrypted(unsigned long phys_addr,
 422                                       unsigned long size);
 423
 424 #endif /* _ASM_X86_IO_H */