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", 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
 191 extern void __iomem *ioremap_cache(resource_size_t offset, unsigned long size);
 192 #define ioremap_cache ioremap_cache
 193 extern void __iomem *ioremap_prot(resource_size_t offset, unsigned long size, unsigned long prot_val);
 194 #define ioremap_prot ioremap_prot
 195
 196 /**
 197  * ioremap     -   map bus memory into CPU space
 198  * @offset:    bus address of the memory
 199  * @size:      size of the resource to map
 200  *
 201  * ioremap performs a platform specific sequence of operations to
 202  * make bus memory CPU accessible via the readb/readw/readl/writeb/
 203  * writew/writel functions and the other mmio helpers. The returned
 204  * address is not guaranteed to be usable directly as a virtual
 205  * address.
 206  *
 207  * If the area you are trying to map is a PCI BAR you should have a
 208  * look at pci_iomap().
 209  */
 210 static inline void __iomem *ioremap(resource_size_t offset, unsigned long size)
 211 {
 212         return ioremap_nocache(offset, size);
 213 }
 214 #define ioremap ioremap
 215
 216 extern void iounmap(volatile void __iomem *addr);
 217 #define iounmap iounmap
 218
 219 extern void set_iounmap_nonlazy(void);
 220
 221 #ifdef __KERNEL__
 222
 223 #include <asm-generic/iomap.h>
 224
 225 /*
 226  * ISA space is 'always mapped' on a typical x86 system, no need to
 227  * explicitly ioremap() it. The fact that the ISA IO space is mapped
 228  * to PAGE_OFFSET is pure coincidence - it does not mean ISA values
 229  * are physical addresses. The following constant pointer can be
 230  * used as the IO-area pointer (it can be iounmapped as well, so the
 231  * analogy with PCI is quite large):
 232  */
 233 #define __ISA_IO_base ((char __iomem *)(PAGE_OFFSET))
 234
 235 #endif /* __KERNEL__ */
 236
 237 extern void native_io_delay(void);
 238
 239 extern int io_delay_type;
 240 extern void io_delay_init(void);
 241
 242 #if defined(CONFIG_PARAVIRT)
 243 #include <asm/paravirt.h>
 244 #else
 245
 246 static inline void slow_down_io(void)
 247 {
 248         native_io_delay();
 249 #ifdef REALLY_SLOW_IO
 250         native_io_delay();
 251         native_io_delay();
 252         native_io_delay();
 253 #endif
 254 }
 255
 256 #endif
 257
 258 #ifdef CONFIG_AMD_MEM_ENCRYPT
 259 #include <linux/jump_label.h>
 260
 261 extern struct static_key_false sev_enable_key;
 262 static inline bool sev_key_active(void)
 263 {
 264         return static_branch_unlikely(&sev_enable_key);
 265 }
 266
 267 #else /* !CONFIG_AMD_MEM_ENCRYPT */
 268
 269 static inline bool sev_key_active(void) { return false; }
 270
 271 #endif /* CONFIG_AMD_MEM_ENCRYPT */
 272
 273 #define BUILDIO(bwl, bw, type)                                          \
 274 static inline void out##bwl(unsigned type value, int port)              \
 275 {                                                                       \
 276         asm volatile("out" #bwl " %" #bw "0, %w1"                       \
 277                      : : "a"(value), "Nd"(port));                       \
 278 }                                                                       \
 279                                                                         \
 280 static inline unsigned type in##bwl(int port)                           \
 281 {                                                                       \
 282         unsigned type value;                                            \
 283         asm volatile("in" #bwl " %w1, %" #bw "0"                        \
 284                      : "=a"(value) : "Nd"(port));                       \
 285         return value;                                                   \
 286 }                                                                       \
 287                                                                         \
 288 static inline void out##bwl##_p(unsigned type value, int port)          \
 289 {                                                                       \
 290         out##bwl(value, port);                                          \
 291         slow_down_io();                                                 \
 292 }                                                                       \
 293                                                                         \
 294 static inline unsigned type in##bwl##_p(int port)                       \
 295 {                                                                       \
 296         unsigned type value = in##bwl(port);                            \
 297         slow_down_io();                                                 \
 298         return value;                                                   \
 299 }                                                                       \
 300                                                                         \
 301 static inline void outs##bwl(int port, const void *addr, unsigned long count) \
 302 {                                                                       \
 303         if (sev_key_active()) {                                         \
 304                 unsigned type *value = (unsigned type *)addr;           \
 305                 while (count) {                                         \
 306                         out##bwl(*value, port);                         \
 307                         value++;                                        \
 308                         count--;                                        \
 309                 }                                                       \
 310         } else {                                                        \
 311                 asm volatile("rep; outs" #bwl                           \
 312                              : "+S"(addr), "+c"(count)                  \
 313                              : "d"(port) : "memory");                   \
 314         }                                                               \
 315 }                                                                       \
 316                                                                         \
 317 static inline void ins##bwl(int port, void *addr, unsigned long count)  \
 318 {                                                                       \
 319         if (sev_key_active()) {                                         \
 320                 unsigned type *value = (unsigned type *)addr;           \
 321                 while (count) {                                         \
 322                         *value = in##bwl(port);                         \
 323                         value++;                                        \
 324                         count--;                                        \
 325                 }                                                       \
 326         } else {                                                        \
 327                 asm volatile("rep; ins" #bwl                            \
 328                              : "+D"(addr), "+c"(count)                  \
 329                              : "d"(port) : "memory");                   \
 330         }                                                               \
 331 }
 332
 333 BUILDIO(b, b, char)
 334 BUILDIO(w, w, short)
 335 BUILDIO(l, , int)
 336
 337 #define inb inb
 338 #define inw inw
 339 #define inl inl
 340 #define inb_p inb_p
 341 #define inw_p inw_p
 342 #define inl_p inl_p
 343 #define insb insb
 344 #define insw insw
 345 #define insl insl
 346
 347 #define outb outb
 348 #define outw outw
 349 #define outl outl
 350 #define outb_p outb_p
 351 #define outw_p outw_p
 352 #define outl_p outl_p
 353 #define outsb outsb
 354 #define outsw outsw
 355 #define outsl outsl
 356
 357 extern void *xlate_dev_mem_ptr(phys_addr_t phys);
 358 extern void unxlate_dev_mem_ptr(phys_addr_t phys, void *addr);
 359
 360 #define xlate_dev_mem_ptr xlate_dev_mem_ptr
 361 #define unxlate_dev_mem_ptr unxlate_dev_mem_ptr
 362
 363 extern int ioremap_change_attr(unsigned long vaddr, unsigned long size,
 364                                 enum page_cache_mode pcm);
 365 extern void __iomem *ioremap_wc(resource_size_t offset, unsigned long size);
 366 #define ioremap_wc ioremap_wc
 367 extern void __iomem *ioremap_wt(resource_size_t offset, unsigned long size);
 368 #define ioremap_wt ioremap_wt
 369
 370 extern bool is_early_ioremap_ptep(pte_t *ptep);
 371
 372 #ifdef CONFIG_XEN
 373 #include <xen/xen.h>
 374 struct bio_vec;
 375
 376 extern bool xen_biovec_phys_mergeable(const struct bio_vec *vec1,
 377                                       const struct bio_vec *vec2);
 378
 379 #define BIOVEC_PHYS_MERGEABLE(vec1, vec2)                               \
 380         (__BIOVEC_PHYS_MERGEABLE(vec1, vec2) &&                         \
 381          (!xen_domain() || xen_biovec_phys_mergeable(vec1, vec2)))
 382 #endif  /* CONFIG_XEN */
 383
 384 #define IO_SPACE_LIMIT 0xffff
 385
 386 #include <asm-generic/io.h>
 387 #undef PCI_IOBASE
 388
 389 #ifdef CONFIG_MTRR
 390 extern int __must_check arch_phys_wc_index(int handle);
 391 #define arch_phys_wc_index arch_phys_wc_index
 392
 393 extern int __must_check arch_phys_wc_add(unsigned long base,
 394                                          unsigned long size);
 395 extern void arch_phys_wc_del(int handle);
 396 #define arch_phys_wc_add arch_phys_wc_add
 397 #endif
 398
 399 #ifdef CONFIG_X86_PAT
 400 extern int arch_io_reserve_memtype_wc(resource_size_t start, resource_size_t size);
 401 extern void arch_io_free_memtype_wc(resource_size_t start, resource_size_t size);
 402 #define arch_io_reserve_memtype_wc arch_io_reserve_memtype_wc
 403 #endif
 404
 405 extern bool arch_memremap_can_ram_remap(resource_size_t offset,
 406                                         unsigned long size,
 407                                         unsigned long flags);
 408 #define arch_memremap_can_ram_remap arch_memremap_can_ram_remap
 409
 410 extern bool phys_mem_access_encrypted(unsigned long phys_addr,
 411                                       unsigned long size);
 412
 413 #endif /* _ASM_X86_IO_H */