linux/arch/arm/include/asm/io.h
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   1/* SPDX-License-Identifier: GPL-2.0-only */
   2/*
   3 *  arch/arm/include/asm/io.h
   4 *
   5 *  Copyright (C) 1996-2000 Russell King
   6 *
   7 * Modifications:
   8 *  16-Sep-1996 RMK     Inlined the inx/outx functions & optimised for both
   9 *                      constant addresses and variable addresses.
  10 *  04-Dec-1997 RMK     Moved a lot of this stuff to the new architecture
  11 *                      specific IO header files.
  12 *  27-Mar-1999 PJB     Second parameter of memcpy_toio is const..
  13 *  04-Apr-1999 PJB     Added check_signature.
  14 *  12-Dec-1999 RMK     More cleanups
  15 *  18-Jun-2000 RMK     Removed virt_to_* and friends definitions
  16 *  05-Oct-2004 BJD     Moved memory string functions to use void __iomem
  17 */
  18#ifndef __ASM_ARM_IO_H
  19#define __ASM_ARM_IO_H
  20
  21#ifdef __KERNEL__
  22
  23#include <linux/string.h>
  24#include <linux/types.h>
  25#include <asm/byteorder.h>
  26#include <asm/memory.h>
  27#include <asm-generic/pci_iomap.h>
  28
  29/*
  30 * ISA I/O bus memory addresses are 1:1 with the physical address.
  31 */
  32#define isa_virt_to_bus virt_to_phys
  33#define isa_bus_to_virt phys_to_virt
  34
  35/*
  36 * Atomic MMIO-wide IO modify
  37 */
  38extern void atomic_io_modify(void __iomem *reg, u32 mask, u32 set);
  39extern void atomic_io_modify_relaxed(void __iomem *reg, u32 mask, u32 set);
  40
  41/*
  42 * Generic IO read/write.  These perform native-endian accesses.  Note
  43 * that some architectures will want to re-define __raw_{read,write}w.
  44 */
  45void __raw_writesb(volatile void __iomem *addr, const void *data, int bytelen);
  46void __raw_writesw(volatile void __iomem *addr, const void *data, int wordlen);
  47void __raw_writesl(volatile void __iomem *addr, const void *data, int longlen);
  48
  49void __raw_readsb(const volatile void __iomem *addr, void *data, int bytelen);
  50void __raw_readsw(const volatile void __iomem *addr, void *data, int wordlen);
  51void __raw_readsl(const volatile void __iomem *addr, void *data, int longlen);
  52
  53#if __LINUX_ARM_ARCH__ < 6
  54/*
  55 * Half-word accesses are problematic with RiscPC due to limitations of
  56 * the bus. Rather than special-case the machine, just let the compiler
  57 * generate the access for CPUs prior to ARMv6.
  58 */
  59#define __raw_readw(a)         (__chk_io_ptr(a), *(volatile unsigned short __force *)(a))
  60#define __raw_writew(v,a)      ((void)(__chk_io_ptr(a), *(volatile unsigned short __force *)(a) = (v)))
  61#else
  62/*
  63 * When running under a hypervisor, we want to avoid I/O accesses with
  64 * writeback addressing modes as these incur a significant performance
  65 * overhead (the address generation must be emulated in software).
  66 */
  67#define __raw_writew __raw_writew
  68static inline void __raw_writew(u16 val, volatile void __iomem *addr)
  69{
  70        asm volatile("strh %1, %0"
  71                     : : "Q" (*(volatile u16 __force *)addr), "r" (val));
  72}
  73
  74#define __raw_readw __raw_readw
  75static inline u16 __raw_readw(const volatile void __iomem *addr)
  76{
  77        u16 val;
  78        asm volatile("ldrh %0, %1"
  79                     : "=r" (val)
  80                     : "Q" (*(volatile u16 __force *)addr));
  81        return val;
  82}
  83#endif
  84
  85#define __raw_writeb __raw_writeb
  86static inline void __raw_writeb(u8 val, volatile void __iomem *addr)
  87{
  88        asm volatile("strb %1, %0"
  89                     : : "Qo" (*(volatile u8 __force *)addr), "r" (val));
  90}
  91
  92#define __raw_writel __raw_writel
  93static inline void __raw_writel(u32 val, volatile void __iomem *addr)
  94{
  95        asm volatile("str %1, %0"
  96                     : : "Qo" (*(volatile u32 __force *)addr), "r" (val));
  97}
  98
  99#define __raw_readb __raw_readb
 100static inline u8 __raw_readb(const volatile void __iomem *addr)
 101{
 102        u8 val;
 103        asm volatile("ldrb %0, %1"
 104                     : "=r" (val)
 105                     : "Qo" (*(volatile u8 __force *)addr));
 106        return val;
 107}
 108
 109#define __raw_readl __raw_readl
 110static inline u32 __raw_readl(const volatile void __iomem *addr)
 111{
 112        u32 val;
 113        asm volatile("ldr %0, %1"
 114                     : "=r" (val)
 115                     : "Qo" (*(volatile u32 __force *)addr));
 116        return val;
 117}
 118
 119/*
 120 * Architecture ioremap implementation.
 121 */
 122#define MT_DEVICE               0
 123#define MT_DEVICE_NONSHARED     1
 124#define MT_DEVICE_CACHED        2
 125#define MT_DEVICE_WC            3
 126/*
 127 * types 4 onwards can be found in asm/mach/map.h and are undefined
 128 * for ioremap
 129 */
 130
 131/*
 132 * __arm_ioremap takes CPU physical address.
 133 * __arm_ioremap_pfn takes a Page Frame Number and an offset into that page
 134 * The _caller variety takes a __builtin_return_address(0) value for
 135 * /proc/vmalloc to use - and should only be used in non-inline functions.
 136 */
 137extern void __iomem *__arm_ioremap_caller(phys_addr_t, size_t, unsigned int,
 138        void *);
 139extern void __iomem *__arm_ioremap_pfn(unsigned long, unsigned long, size_t, unsigned int);
 140extern void __iomem *__arm_ioremap_exec(phys_addr_t, size_t, bool cached);
 141extern void __iounmap(volatile void __iomem *addr);
 142
 143extern void __iomem * (*arch_ioremap_caller)(phys_addr_t, size_t,
 144        unsigned int, void *);
 145extern void (*arch_iounmap)(volatile void __iomem *);
 146
 147/*
 148 * Bad read/write accesses...
 149 */
 150extern void __readwrite_bug(const char *fn);
 151
 152/*
 153 * A typesafe __io() helper
 154 */
 155static inline void __iomem *__typesafe_io(unsigned long addr)
 156{
 157        return (void __iomem *)addr;
 158}
 159
 160#define IOMEM(x)        ((void __force __iomem *)(x))
 161
 162/* IO barriers */
 163#ifdef CONFIG_ARM_DMA_MEM_BUFFERABLE
 164#include <asm/barrier.h>
 165#define __iormb()               rmb()
 166#define __iowmb()               wmb()
 167#else
 168#define __iormb()               do { } while (0)
 169#define __iowmb()               do { } while (0)
 170#endif
 171
 172/* PCI fixed i/o mapping */
 173#define PCI_IO_VIRT_BASE        0xfee00000
 174#define PCI_IOBASE              ((void __iomem *)PCI_IO_VIRT_BASE)
 175
 176#if defined(CONFIG_PCI)
 177void pci_ioremap_set_mem_type(int mem_type);
 178#else
 179static inline void pci_ioremap_set_mem_type(int mem_type) {}
 180#endif
 181
 182extern int pci_ioremap_io(unsigned int offset, phys_addr_t phys_addr);
 183
 184/*
 185 * PCI configuration space mapping function.
 186 *
 187 * The PCI specification does not allow configuration write
 188 * transactions to be posted. Add an arch specific
 189 * pci_remap_cfgspace() definition that is implemented
 190 * through strongly ordered memory mappings.
 191 */
 192#define pci_remap_cfgspace pci_remap_cfgspace
 193void __iomem *pci_remap_cfgspace(resource_size_t res_cookie, size_t size);
 194/*
 195 * Now, pick up the machine-defined IO definitions
 196 */
 197#ifdef CONFIG_NEED_MACH_IO_H
 198#include <mach/io.h>
 199#elif defined(CONFIG_PCI)
 200#define IO_SPACE_LIMIT  ((resource_size_t)0xfffff)
 201#define __io(a)         __typesafe_io(PCI_IO_VIRT_BASE + ((a) & IO_SPACE_LIMIT))
 202#else
 203#define __io(a)         __typesafe_io((a) & IO_SPACE_LIMIT)
 204#endif
 205
 206/*
 207 * This is the limit of PC card/PCI/ISA IO space, which is by default
 208 * 64K if we have PC card, PCI or ISA support.  Otherwise, default to
 209 * zero to prevent ISA/PCI drivers claiming IO space (and potentially
 210 * oopsing.)
 211 *
 212 * Only set this larger if you really need inb() et.al. to operate over
 213 * a larger address space.  Note that SOC_COMMON ioremaps each sockets
 214 * IO space area, and so inb() et.al. must be defined to operate as per
 215 * readb() et.al. on such platforms.
 216 */
 217#ifndef IO_SPACE_LIMIT
 218#if defined(CONFIG_PCMCIA_SOC_COMMON) || defined(CONFIG_PCMCIA_SOC_COMMON_MODULE)
 219#define IO_SPACE_LIMIT ((resource_size_t)0xffffffff)
 220#elif defined(CONFIG_PCI) || defined(CONFIG_ISA) || defined(CONFIG_PCCARD)
 221#define IO_SPACE_LIMIT ((resource_size_t)0xffff)
 222#else
 223#define IO_SPACE_LIMIT ((resource_size_t)0)
 224#endif
 225#endif
 226
 227/*
 228 *  IO port access primitives
 229 *  -------------------------
 230 *
 231 * The ARM doesn't have special IO access instructions; all IO is memory
 232 * mapped.  Note that these are defined to perform little endian accesses
 233 * only.  Their primary purpose is to access PCI and ISA peripherals.
 234 *
 235 * Note that for a big endian machine, this implies that the following
 236 * big endian mode connectivity is in place, as described by numerous
 237 * ARM documents:
 238 *
 239 *    PCI:  D0-D7   D8-D15 D16-D23 D24-D31
 240 *    ARM: D24-D31 D16-D23  D8-D15  D0-D7
 241 *
 242 * The machine specific io.h include defines __io to translate an "IO"
 243 * address to a memory address.
 244 *
 245 * Note that we prevent GCC re-ordering or caching values in expressions
 246 * by introducing sequence points into the in*() definitions.  Note that
 247 * __raw_* do not guarantee this behaviour.
 248 *
 249 * The {in,out}[bwl] macros are for emulating x86-style PCI/ISA IO space.
 250 */
 251#ifdef __io
 252#define outb(v,p)       ({ __iowmb(); __raw_writeb(v,__io(p)); })
 253#define outw(v,p)       ({ __iowmb(); __raw_writew((__force __u16) \
 254                                        cpu_to_le16(v),__io(p)); })
 255#define outl(v,p)       ({ __iowmb(); __raw_writel((__force __u32) \
 256                                        cpu_to_le32(v),__io(p)); })
 257
 258#define inb(p)  ({ __u8 __v = __raw_readb(__io(p)); __iormb(); __v; })
 259#define inw(p)  ({ __u16 __v = le16_to_cpu((__force __le16) \
 260                        __raw_readw(__io(p))); __iormb(); __v; })
 261#define inl(p)  ({ __u32 __v = le32_to_cpu((__force __le32) \
 262                        __raw_readl(__io(p))); __iormb(); __v; })
 263
 264#define outsb(p,d,l)            __raw_writesb(__io(p),d,l)
 265#define outsw(p,d,l)            __raw_writesw(__io(p),d,l)
 266#define outsl(p,d,l)            __raw_writesl(__io(p),d,l)
 267
 268#define insb(p,d,l)             __raw_readsb(__io(p),d,l)
 269#define insw(p,d,l)             __raw_readsw(__io(p),d,l)
 270#define insl(p,d,l)             __raw_readsl(__io(p),d,l)
 271#endif
 272
 273/*
 274 * String version of IO memory access ops:
 275 */
 276extern void _memcpy_fromio(void *, const volatile void __iomem *, size_t);
 277extern void _memcpy_toio(volatile void __iomem *, const void *, size_t);
 278extern void _memset_io(volatile void __iomem *, int, size_t);
 279
 280/*
 281 *  Memory access primitives
 282 *  ------------------------
 283 *
 284 * These perform PCI memory accesses via an ioremap region.  They don't
 285 * take an address as such, but a cookie.
 286 *
 287 * Again, these are defined to perform little endian accesses.  See the
 288 * IO port primitives for more information.
 289 */
 290#ifndef readl
 291#define readb_relaxed(c) ({ u8  __r = __raw_readb(c); __r; })
 292#define readw_relaxed(c) ({ u16 __r = le16_to_cpu((__force __le16) \
 293                                        __raw_readw(c)); __r; })
 294#define readl_relaxed(c) ({ u32 __r = le32_to_cpu((__force __le32) \
 295                                        __raw_readl(c)); __r; })
 296
 297#define writeb_relaxed(v,c)     __raw_writeb(v,c)
 298#define writew_relaxed(v,c)     __raw_writew((__force u16) cpu_to_le16(v),c)
 299#define writel_relaxed(v,c)     __raw_writel((__force u32) cpu_to_le32(v),c)
 300
 301#define readb(c)                ({ u8  __v = readb_relaxed(c); __iormb(); __v; })
 302#define readw(c)                ({ u16 __v = readw_relaxed(c); __iormb(); __v; })
 303#define readl(c)                ({ u32 __v = readl_relaxed(c); __iormb(); __v; })
 304
 305#define writeb(v,c)             ({ __iowmb(); writeb_relaxed(v,c); })
 306#define writew(v,c)             ({ __iowmb(); writew_relaxed(v,c); })
 307#define writel(v,c)             ({ __iowmb(); writel_relaxed(v,c); })
 308
 309#define readsb(p,d,l)           __raw_readsb(p,d,l)
 310#define readsw(p,d,l)           __raw_readsw(p,d,l)
 311#define readsl(p,d,l)           __raw_readsl(p,d,l)
 312
 313#define writesb(p,d,l)          __raw_writesb(p,d,l)
 314#define writesw(p,d,l)          __raw_writesw(p,d,l)
 315#define writesl(p,d,l)          __raw_writesl(p,d,l)
 316
 317#ifndef __ARMBE__
 318static inline void memset_io(volatile void __iomem *dst, unsigned c,
 319        size_t count)
 320{
 321        extern void mmioset(void *, unsigned int, size_t);
 322        mmioset((void __force *)dst, c, count);
 323}
 324#define memset_io(dst,c,count) memset_io(dst,c,count)
 325
 326static inline void memcpy_fromio(void *to, const volatile void __iomem *from,
 327        size_t count)
 328{
 329        extern void mmiocpy(void *, const void *, size_t);
 330        mmiocpy(to, (const void __force *)from, count);
 331}
 332#define memcpy_fromio(to,from,count) memcpy_fromio(to,from,count)
 333
 334static inline void memcpy_toio(volatile void __iomem *to, const void *from,
 335        size_t count)
 336{
 337        extern void mmiocpy(void *, const void *, size_t);
 338        mmiocpy((void __force *)to, from, count);
 339}
 340#define memcpy_toio(to,from,count) memcpy_toio(to,from,count)
 341
 342#else
 343#define memset_io(c,v,l)        _memset_io(c,(v),(l))
 344#define memcpy_fromio(a,c,l)    _memcpy_fromio((a),c,(l))
 345#define memcpy_toio(c,a,l)      _memcpy_toio(c,(a),(l))
 346#endif
 347
 348#endif  /* readl */
 349
 350/*
 351 * ioremap() and friends.
 352 *
 353 * ioremap() takes a resource address, and size.  Due to the ARM memory
 354 * types, it is important to use the correct ioremap() function as each
 355 * mapping has specific properties.
 356 *
 357 * Function             Memory type     Cacheability    Cache hint
 358 * ioremap()            Device          n/a             n/a
 359 * ioremap_nocache()    Device          n/a             n/a
 360 * ioremap_cache()      Normal          Writeback       Read allocate
 361 * ioremap_wc()         Normal          Non-cacheable   n/a
 362 * ioremap_wt()         Normal          Non-cacheable   n/a
 363 *
 364 * All device mappings have the following properties:
 365 * - no access speculation
 366 * - no repetition (eg, on return from an exception)
 367 * - number, order and size of accesses are maintained
 368 * - unaligned accesses are "unpredictable"
 369 * - writes may be delayed before they hit the endpoint device
 370 *
 371 * ioremap_nocache() is the same as ioremap() as there are too many device
 372 * drivers using this for device registers, and documentation which tells
 373 * people to use it for such for this to be any different.  This is not a
 374 * safe fallback for memory-like mappings, or memory regions where the
 375 * compiler may generate unaligned accesses - eg, via inlining its own
 376 * memcpy.
 377 *
 378 * All normal memory mappings have the following properties:
 379 * - reads can be repeated with no side effects
 380 * - repeated reads return the last value written
 381 * - reads can fetch additional locations without side effects
 382 * - writes can be repeated (in certain cases) with no side effects
 383 * - writes can be merged before accessing the target
 384 * - unaligned accesses can be supported
 385 * - ordering is not guaranteed without explicit dependencies or barrier
 386 *   instructions
 387 * - writes may be delayed before they hit the endpoint memory
 388 *
 389 * The cache hint is only a performance hint: CPUs may alias these hints.
 390 * Eg, a CPU not implementing read allocate but implementing write allocate
 391 * will provide a write allocate mapping instead.
 392 */
 393void __iomem *ioremap(resource_size_t res_cookie, size_t size);
 394#define ioremap ioremap
 395#define ioremap_nocache ioremap
 396
 397/*
 398 * Do not use ioremap_cache for mapping memory. Use memremap instead.
 399 */
 400void __iomem *ioremap_cache(resource_size_t res_cookie, size_t size);
 401#define ioremap_cache ioremap_cache
 402
 403/*
 404 * Do not use ioremap_cached in new code. Provided for the benefit of
 405 * the pxa2xx-flash MTD driver only.
 406 */
 407void __iomem *ioremap_cached(resource_size_t res_cookie, size_t size);
 408
 409void __iomem *ioremap_wc(resource_size_t res_cookie, size_t size);
 410#define ioremap_wc ioremap_wc
 411#define ioremap_wt ioremap_wc
 412
 413void iounmap(volatile void __iomem *iomem_cookie);
 414#define iounmap iounmap
 415
 416void *arch_memremap_wb(phys_addr_t phys_addr, size_t size);
 417#define arch_memremap_wb arch_memremap_wb
 418
 419/*
 420 * io{read,write}{16,32}be() macros
 421 */
 422#define ioread16be(p)           ({ __u16 __v = be16_to_cpu((__force __be16)__raw_readw(p)); __iormb(); __v; })
 423#define ioread32be(p)           ({ __u32 __v = be32_to_cpu((__force __be32)__raw_readl(p)); __iormb(); __v; })
 424
 425#define iowrite16be(v,p)        ({ __iowmb(); __raw_writew((__force __u16)cpu_to_be16(v), p); })
 426#define iowrite32be(v,p)        ({ __iowmb(); __raw_writel((__force __u32)cpu_to_be32(v), p); })
 427
 428#ifndef ioport_map
 429#define ioport_map ioport_map
 430extern void __iomem *ioport_map(unsigned long port, unsigned int nr);
 431#endif
 432#ifndef ioport_unmap
 433#define ioport_unmap ioport_unmap
 434extern void ioport_unmap(void __iomem *addr);
 435#endif
 436
 437struct pci_dev;
 438
 439#define pci_iounmap pci_iounmap
 440extern void pci_iounmap(struct pci_dev *dev, void __iomem *addr);
 441
 442/*
 443 * Convert a physical pointer to a virtual kernel pointer for /dev/mem
 444 * access
 445 */
 446#define xlate_dev_mem_ptr(p)    __va(p)
 447
 448/*
 449 * Convert a virtual cached pointer to an uncached pointer
 450 */
 451#define xlate_dev_kmem_ptr(p)   p
 452
 453#include <asm-generic/io.h>
 454
 455#ifdef CONFIG_MMU
 456#define ARCH_HAS_VALID_PHYS_ADDR_RANGE
 457extern int valid_phys_addr_range(phys_addr_t addr, size_t size);
 458extern int valid_mmap_phys_addr_range(unsigned long pfn, size_t size);
 459extern int devmem_is_allowed(unsigned long pfn);
 460#endif
 461
 462/*
 463 * Register ISA memory and port locations for glibc iopl/inb/outb
 464 * emulation.
 465 */
 466extern void register_isa_ports(unsigned int mmio, unsigned int io,
 467                               unsigned int io_shift);
 468
 469#endif  /* __KERNEL__ */
 470#endif  /* __ASM_ARM_IO_H */
 471