root/arch/x86/include/asm/io.h

INCLUDED FROM

DEFINITIONS

1. virt_to_phys
2. phys_to_virt
3. isa_virt_to_bus
4. ioremap
5. slow_down_io
6. sev_key_active
7. sev_key_active

   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 #ifdef CONFIG_X86_64
  94 
  95 build_mmio_read(readq, "q", u64, "=r", :"memory")
  96 build_mmio_read(__readq, "q", u64, "=r", )
  97 build_mmio_write(writeq, "q", u64, "r", :"memory")
  98 build_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
 113 extern int valid_phys_addr_range(phys_addr_t addr, size_t size);
 114 extern 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 
 129 static 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 
 148 static 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  */
 164 static 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  */
 183 extern void __iomem *ioremap_nocache(resource_size_t offset, unsigned long size);
 184 #define ioremap_nocache ioremap_nocache
 185 extern void __iomem *ioremap_uc(resource_size_t offset, unsigned long size);
 186 #define ioremap_uc ioremap_uc
 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 extern void __iomem *ioremap_encrypted(resource_size_t phys_addr, unsigned long size);
 192 #define ioremap_encrypted ioremap_encrypted
 193 
 194 /**
 195  * ioremap     -   map bus memory into CPU space
 196  * @offset:    bus address of the memory
 197  * @size:      size of the resource to map
 198  *
 199  * ioremap performs a platform specific sequence of operations to
 200  * make bus memory CPU accessible via the readb/readw/readl/writeb/
 201  * writew/writel functions and the other mmio helpers. The returned
 202  * address is not guaranteed to be usable directly as a virtual
 203  * address.
 204  *
 205  * If the area you are trying to map is a PCI BAR you should have a
 206  * look at pci_iomap().
 207  */
 208 static inline void __iomem *ioremap(resource_size_t offset, unsigned long size)
 209 {
 210         return ioremap_nocache(offset, size);
 211 }
 212 #define ioremap ioremap
 213 
 214 extern void iounmap(volatile void __iomem *addr);
 215 #define iounmap iounmap
 216 
 217 extern void set_iounmap_nonlazy(void);
 218 
 219 #ifdef __KERNEL__
 220 
 221 void memcpy_fromio(void *, const volatile void __iomem *, size_t);
 222 void memcpy_toio(volatile void __iomem *, const void *, size_t);
 223 void memset_io(volatile void __iomem *, int, size_t);
 224 
 225 #define memcpy_fromio memcpy_fromio
 226 #define memcpy_toio memcpy_toio
 227 #define memset_io memset_io
 228 
 229 #include <asm-generic/iomap.h>
 230 
 231 /*
 232  * ISA space is 'always mapped' on a typical x86 system, no need to
 233  * explicitly ioremap() it. The fact that the ISA IO space is mapped
 234  * to PAGE_OFFSET is pure coincidence - it does not mean ISA values
 235  * are physical addresses. The following constant pointer can be
 236  * used as the IO-area pointer (it can be iounmapped as well, so the
 237  * analogy with PCI is quite large):
 238  */
 239 #define __ISA_IO_base ((char __iomem *)(PAGE_OFFSET))
 240 
 241 #endif /* __KERNEL__ */
 242 
 243 extern void native_io_delay(void);
 244 
 245 extern int io_delay_type;
 246 extern void io_delay_init(void);
 247 
 248 #if defined(CONFIG_PARAVIRT)
 249 #include <asm/paravirt.h>
 250 #else
 251 
 252 static inline void slow_down_io(void)
 253 {
 254         native_io_delay();
 255 #ifdef REALLY_SLOW_IO
 256         native_io_delay();
 257         native_io_delay();
 258         native_io_delay();
 259 #endif
 260 }
 261 
 262 #endif
 263 
 264 #ifdef CONFIG_AMD_MEM_ENCRYPT
 265 #include <linux/jump_label.h>
 266 
 267 extern struct static_key_false sev_enable_key;
 268 static inline bool sev_key_active(void)
 269 {
 270         return static_branch_unlikely(&sev_enable_key);
 271 }
 272 
 273 #else /* !CONFIG_AMD_MEM_ENCRYPT */
 274 
 275 static inline bool sev_key_active(void) { return false; }
 276 
 277 #endif /* CONFIG_AMD_MEM_ENCRYPT */
 278 
 279 #define BUILDIO(bwl, bw, type)                                          \
 280 static inline void out##bwl(unsigned type value, int port)              \
 281 {                                                                       \
 282         asm volatile("out" #bwl " %" #bw "0, %w1"                       \
 283                      : : "a"(value), "Nd"(port));                       \
 284 }                                                                       \
 285                                                                         \
 286 static inline unsigned type in##bwl(int port)                           \
 287 {                                                                       \
 288         unsigned type value;                                            \
 289         asm volatile("in" #bwl " %w1, %" #bw "0"                        \
 290                      : "=a"(value) : "Nd"(port));                       \
 291         return value;                                                   \
 292 }                                                                       \
 293                                                                         \
 294 static inline void out##bwl##_p(unsigned type value, int port)          \
 295 {                                                                       \
 296         out##bwl(value, port);                                          \
 297         slow_down_io();                                                 \
 298 }                                                                       \
 299                                                                         \
 300 static inline unsigned type in##bwl##_p(int port)                       \
 301 {                                                                       \
 302         unsigned type value = in##bwl(port);                            \
 303         slow_down_io();                                                 \
 304         return value;                                                   \
 305 }                                                                       \
 306                                                                         \
 307 static inline void outs##bwl(int port, const void *addr, unsigned long count) \
 308 {                                                                       \
 309         if (sev_key_active()) {                                         \
 310                 unsigned type *value = (unsigned type *)addr;           \
 311                 while (count) {                                         \
 312                         out##bwl(*value, port);                         \
 313                         value++;                                        \
 314                         count--;                                        \
 315                 }                                                       \
 316         } else {                                                        \
 317                 asm volatile("rep; outs" #bwl                           \
 318                              : "+S"(addr), "+c"(count)                  \
 319                              : "d"(port) : "memory");                   \
 320         }                                                               \
 321 }                                                                       \
 322                                                                         \
 323 static inline void ins##bwl(int port, void *addr, unsigned long count)  \
 324 {                                                                       \
 325         if (sev_key_active()) {                                         \
 326                 unsigned type *value = (unsigned type *)addr;           \
 327                 while (count) {                                         \
 328                         *value = in##bwl(port);                         \
 329                         value++;                                        \
 330                         count--;                                        \
 331                 }                                                       \
 332         } else {                                                        \
 333                 asm volatile("rep; ins" #bwl                            \
 334                              : "+D"(addr), "+c"(count)                  \
 335                              : "d"(port) : "memory");                   \
 336         }                                                               \
 337 }
 338 
 339 BUILDIO(b, b, char)
 340 BUILDIO(w, w, short)
 341 BUILDIO(l, , int)
 342 
 343 #define inb inb
 344 #define inw inw
 345 #define inl inl
 346 #define inb_p inb_p
 347 #define inw_p inw_p
 348 #define inl_p inl_p
 349 #define insb insb
 350 #define insw insw
 351 #define insl insl
 352 
 353 #define outb outb
 354 #define outw outw
 355 #define outl outl
 356 #define outb_p outb_p
 357 #define outw_p outw_p
 358 #define outl_p outl_p
 359 #define outsb outsb
 360 #define outsw outsw
 361 #define outsl outsl
 362 
 363 extern void *xlate_dev_mem_ptr(phys_addr_t phys);
 364 extern void unxlate_dev_mem_ptr(phys_addr_t phys, void *addr);
 365 
 366 #define xlate_dev_mem_ptr xlate_dev_mem_ptr
 367 #define unxlate_dev_mem_ptr unxlate_dev_mem_ptr
 368 
 369 extern int ioremap_change_attr(unsigned long vaddr, unsigned long size,
 370                                 enum page_cache_mode pcm);
 371 extern void __iomem *ioremap_wc(resource_size_t offset, unsigned long size);
 372 #define ioremap_wc ioremap_wc
 373 extern void __iomem *ioremap_wt(resource_size_t offset, unsigned long size);
 374 #define ioremap_wt ioremap_wt
 375 
 376 extern bool is_early_ioremap_ptep(pte_t *ptep);
 377 
 378 #define IO_SPACE_LIMIT 0xffff
 379 
 380 #include <asm-generic/io.h>
 381 #undef PCI_IOBASE
 382 
 383 #ifdef CONFIG_MTRR
 384 extern int __must_check arch_phys_wc_index(int handle);
 385 #define arch_phys_wc_index arch_phys_wc_index
 386 
 387 extern int __must_check arch_phys_wc_add(unsigned long base,
 388                                          unsigned long size);
 389 extern void arch_phys_wc_del(int handle);
 390 #define arch_phys_wc_add arch_phys_wc_add
 391 #endif
 392 
 393 #ifdef CONFIG_X86_PAT
 394 extern int arch_io_reserve_memtype_wc(resource_size_t start, resource_size_t size);
 395 extern void arch_io_free_memtype_wc(resource_size_t start, resource_size_t size);
 396 #define arch_io_reserve_memtype_wc arch_io_reserve_memtype_wc
 397 #endif
 398 
 399 extern bool arch_memremap_can_ram_remap(resource_size_t offset,
 400                                         unsigned long size,
 401                                         unsigned long flags);
 402 #define arch_memremap_can_ram_remap arch_memremap_can_ram_remap
 403 
 404 extern bool phys_mem_access_encrypted(unsigned long phys_addr,
 405                                       unsigned long size);
 406 
 407 #endif /* _ASM_X86_IO_H */