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);
 141void __arm_iomem_set_ro(void __iomem *ptr, size_t size);
 142extern void __iounmap(volatile void __iomem *addr);
 143
 144extern void __iomem * (*arch_ioremap_caller)(phys_addr_t, size_t,
 145        unsigned int, void *);
 146extern void (*arch_iounmap)(volatile void __iomem *);
 147
 148/*
 149 * Bad read/write accesses...
 150 */
 151extern void __readwrite_bug(const char *fn);
 152
 153/*
 154 * A typesafe __io() helper
 155 */
 156static inline void __iomem *__typesafe_io(unsigned long addr)
 157{
 158        return (void __iomem *)addr;
 159}
 160
 161#define IOMEM(x)        ((void __force __iomem *)(x))
 162
 163/* IO barriers */
 164#ifdef CONFIG_ARM_DMA_MEM_BUFFERABLE
 165#include <asm/barrier.h>
 166#define __iormb()               rmb()
 167#define __iowmb()               wmb()
 168#else
 169#define __iormb()               do { } while (0)
 170#define __iowmb()               do { } while (0)
 171#endif
 172
 173/* PCI fixed i/o mapping */
 174#define PCI_IO_VIRT_BASE        0xfee00000
 175#define PCI_IOBASE              ((void __iomem *)PCI_IO_VIRT_BASE)
 176
 177#if defined(CONFIG_PCI) || IS_ENABLED(CONFIG_PCMCIA)
 178void pci_ioremap_set_mem_type(int mem_type);
 179#else
 180static inline void pci_ioremap_set_mem_type(int mem_type) {}
 181#endif
 182
 183struct resource;
 184
 185#define pci_remap_iospace pci_remap_iospace
 186int pci_remap_iospace(const struct resource *res, phys_addr_t phys_addr);
 187
 188/*
 189 * PCI configuration space mapping function.
 190 *
 191 * The PCI specification does not allow configuration write
 192 * transactions to be posted. Add an arch specific
 193 * pci_remap_cfgspace() definition that is implemented
 194 * through strongly ordered memory mappings.
 195 */
 196#define pci_remap_cfgspace pci_remap_cfgspace
 197void __iomem *pci_remap_cfgspace(resource_size_t res_cookie, size_t size);
 198/*
 199 * Now, pick up the machine-defined IO definitions
 200 */
 201#ifdef CONFIG_NEED_MACH_IO_H
 202#include <mach/io.h>
 203#else
 204#if IS_ENABLED(CONFIG_PCMCIA) || defined(CONFIG_PCI)
 205#define IO_SPACE_LIMIT  ((resource_size_t)0xfffff)
 206#else
 207#define IO_SPACE_LIMIT ((resource_size_t)0)
 208#endif
 209#define __io(a)         __typesafe_io(PCI_IO_VIRT_BASE + ((a) & IO_SPACE_LIMIT))
 210#endif
 211
 212/*
 213 *  IO port access primitives
 214 *  -------------------------
 215 *
 216 * The ARM doesn't have special IO access instructions; all IO is memory
 217 * mapped.  Note that these are defined to perform little endian accesses
 218 * only.  Their primary purpose is to access PCI and ISA peripherals.
 219 *
 220 * Note that for a big endian machine, this implies that the following
 221 * big endian mode connectivity is in place, as described by numerous
 222 * ARM documents:
 223 *
 224 *    PCI:  D0-D7   D8-D15 D16-D23 D24-D31
 225 *    ARM: D24-D31 D16-D23  D8-D15  D0-D7
 226 *
 227 * The machine specific io.h include defines __io to translate an "IO"
 228 * address to a memory address.
 229 *
 230 * Note that we prevent GCC re-ordering or caching values in expressions
 231 * by introducing sequence points into the in*() definitions.  Note that
 232 * __raw_* do not guarantee this behaviour.
 233 *
 234 * The {in,out}[bwl] macros are for emulating x86-style PCI/ISA IO space.
 235 */
 236#ifdef __io
 237#define outb(v,p)       ({ __iowmb(); __raw_writeb(v,__io(p)); })
 238#define outw(v,p)       ({ __iowmb(); __raw_writew((__force __u16) \
 239                                        cpu_to_le16(v),__io(p)); })
 240#define outl(v,p)       ({ __iowmb(); __raw_writel((__force __u32) \
 241                                        cpu_to_le32(v),__io(p)); })
 242
 243#define inb(p)  ({ __u8 __v = __raw_readb(__io(p)); __iormb(); __v; })
 244#define inw(p)  ({ __u16 __v = le16_to_cpu((__force __le16) \
 245                        __raw_readw(__io(p))); __iormb(); __v; })
 246#define inl(p)  ({ __u32 __v = le32_to_cpu((__force __le32) \
 247                        __raw_readl(__io(p))); __iormb(); __v; })
 248
 249#define outsb(p,d,l)            __raw_writesb(__io(p),d,l)
 250#define outsw(p,d,l)            __raw_writesw(__io(p),d,l)
 251#define outsl(p,d,l)            __raw_writesl(__io(p),d,l)
 252
 253#define insb(p,d,l)             __raw_readsb(__io(p),d,l)
 254#define insw(p,d,l)             __raw_readsw(__io(p),d,l)
 255#define insl(p,d,l)             __raw_readsl(__io(p),d,l)
 256#endif
 257
 258/*
 259 * String version of IO memory access ops:
 260 */
 261extern void _memcpy_fromio(void *, const volatile void __iomem *, size_t);
 262extern void _memcpy_toio(volatile void __iomem *, const void *, size_t);
 263extern void _memset_io(volatile void __iomem *, int, size_t);
 264
 265/*
 266 *  Memory access primitives
 267 *  ------------------------
 268 *
 269 * These perform PCI memory accesses via an ioremap region.  They don't
 270 * take an address as such, but a cookie.
 271 *
 272 * Again, these are defined to perform little endian accesses.  See the
 273 * IO port primitives for more information.
 274 */
 275#ifndef readl
 276#define readb_relaxed(c) ({ u8  __r = __raw_readb(c); __r; })
 277#define readw_relaxed(c) ({ u16 __r = le16_to_cpu((__force __le16) \
 278                                        __raw_readw(c)); __r; })
 279#define readl_relaxed(c) ({ u32 __r = le32_to_cpu((__force __le32) \
 280                                        __raw_readl(c)); __r; })
 281
 282#define writeb_relaxed(v,c)     __raw_writeb(v,c)
 283#define writew_relaxed(v,c)     __raw_writew((__force u16) cpu_to_le16(v),c)
 284#define writel_relaxed(v,c)     __raw_writel((__force u32) cpu_to_le32(v),c)
 285
 286#define readb(c)                ({ u8  __v = readb_relaxed(c); __iormb(); __v; })
 287#define readw(c)                ({ u16 __v = readw_relaxed(c); __iormb(); __v; })
 288#define readl(c)                ({ u32 __v = readl_relaxed(c); __iormb(); __v; })
 289
 290#define writeb(v,c)             ({ __iowmb(); writeb_relaxed(v,c); })
 291#define writew(v,c)             ({ __iowmb(); writew_relaxed(v,c); })
 292#define writel(v,c)             ({ __iowmb(); writel_relaxed(v,c); })
 293
 294#define readsb(p,d,l)           __raw_readsb(p,d,l)
 295#define readsw(p,d,l)           __raw_readsw(p,d,l)
 296#define readsl(p,d,l)           __raw_readsl(p,d,l)
 297
 298#define writesb(p,d,l)          __raw_writesb(p,d,l)
 299#define writesw(p,d,l)          __raw_writesw(p,d,l)
 300#define writesl(p,d,l)          __raw_writesl(p,d,l)
 301
 302#ifndef __ARMBE__
 303static inline void memset_io(volatile void __iomem *dst, unsigned c,
 304        size_t count)
 305{
 306        extern void mmioset(void *, unsigned int, size_t);
 307        mmioset((void __force *)dst, c, count);
 308}
 309#define memset_io(dst,c,count) memset_io(dst,c,count)
 310
 311static inline void memcpy_fromio(void *to, const volatile void __iomem *from,
 312        size_t count)
 313{
 314        extern void mmiocpy(void *, const void *, size_t);
 315        mmiocpy(to, (const void __force *)from, count);
 316}
 317#define memcpy_fromio(to,from,count) memcpy_fromio(to,from,count)
 318
 319static inline void memcpy_toio(volatile void __iomem *to, const void *from,
 320        size_t count)
 321{
 322        extern void mmiocpy(void *, const void *, size_t);
 323        mmiocpy((void __force *)to, from, count);
 324}
 325#define memcpy_toio(to,from,count) memcpy_toio(to,from,count)
 326
 327#else
 328#define memset_io(c,v,l)        _memset_io(c,(v),(l))
 329#define memcpy_fromio(a,c,l)    _memcpy_fromio((a),c,(l))
 330#define memcpy_toio(c,a,l)      _memcpy_toio(c,(a),(l))
 331#endif
 332
 333#endif  /* readl */
 334
 335/*
 336 * ioremap() and friends.
 337 *
 338 * ioremap() takes a resource address, and size.  Due to the ARM memory
 339 * types, it is important to use the correct ioremap() function as each
 340 * mapping has specific properties.
 341 *
 342 * Function             Memory type     Cacheability    Cache hint
 343 * ioremap()            Device          n/a             n/a
 344 * ioremap_cache()      Normal          Writeback       Read allocate
 345 * ioremap_wc()         Normal          Non-cacheable   n/a
 346 * ioremap_wt()         Normal          Non-cacheable   n/a
 347 *
 348 * All device mappings have the following properties:
 349 * - no access speculation
 350 * - no repetition (eg, on return from an exception)
 351 * - number, order and size of accesses are maintained
 352 * - unaligned accesses are "unpredictable"
 353 * - writes may be delayed before they hit the endpoint device
 354 *
 355 * All normal memory mappings have the following properties:
 356 * - reads can be repeated with no side effects
 357 * - repeated reads return the last value written
 358 * - reads can fetch additional locations without side effects
 359 * - writes can be repeated (in certain cases) with no side effects
 360 * - writes can be merged before accessing the target
 361 * - unaligned accesses can be supported
 362 * - ordering is not guaranteed without explicit dependencies or barrier
 363 *   instructions
 364 * - writes may be delayed before they hit the endpoint memory
 365 *
 366 * The cache hint is only a performance hint: CPUs may alias these hints.
 367 * Eg, a CPU not implementing read allocate but implementing write allocate
 368 * will provide a write allocate mapping instead.
 369 */
 370void __iomem *ioremap(resource_size_t res_cookie, size_t size);
 371#define ioremap ioremap
 372
 373/*
 374 * Do not use ioremap_cache for mapping memory. Use memremap instead.
 375 */
 376void __iomem *ioremap_cache(resource_size_t res_cookie, size_t size);
 377#define ioremap_cache ioremap_cache
 378
 379void __iomem *ioremap_wc(resource_size_t res_cookie, size_t size);
 380#define ioremap_wc ioremap_wc
 381#define ioremap_wt ioremap_wc
 382
 383void iounmap(volatile void __iomem *iomem_cookie);
 384#define iounmap iounmap
 385
 386void *arch_memremap_wb(phys_addr_t phys_addr, size_t size);
 387#define arch_memremap_wb arch_memremap_wb
 388
 389/*
 390 * io{read,write}{16,32}be() macros
 391 */
 392#define ioread16be(p)           ({ __u16 __v = be16_to_cpu((__force __be16)__raw_readw(p)); __iormb(); __v; })
 393#define ioread32be(p)           ({ __u32 __v = be32_to_cpu((__force __be32)__raw_readl(p)); __iormb(); __v; })
 394
 395#define iowrite16be(v,p)        ({ __iowmb(); __raw_writew((__force __u16)cpu_to_be16(v), p); })
 396#define iowrite32be(v,p)        ({ __iowmb(); __raw_writel((__force __u32)cpu_to_be32(v), p); })
 397
 398#ifndef ioport_map
 399#define ioport_map ioport_map
 400extern void __iomem *ioport_map(unsigned long port, unsigned int nr);
 401#endif
 402#ifndef ioport_unmap
 403#define ioport_unmap ioport_unmap
 404extern void ioport_unmap(void __iomem *addr);
 405#endif
 406
 407struct pci_dev;
 408
 409#define pci_iounmap pci_iounmap
 410extern void pci_iounmap(struct pci_dev *dev, void __iomem *addr);
 411
 412/*
 413 * Convert a physical pointer to a virtual kernel pointer for /dev/mem
 414 * access
 415 */
 416#define xlate_dev_mem_ptr(p)    __va(p)
 417
 418#include <asm-generic/io.h>
 419
 420#ifdef CONFIG_MMU
 421#define ARCH_HAS_VALID_PHYS_ADDR_RANGE
 422extern int valid_phys_addr_range(phys_addr_t addr, size_t size);
 423extern int valid_mmap_phys_addr_range(unsigned long pfn, size_t size);
 424extern bool arch_memremap_can_ram_remap(resource_size_t offset, size_t size,
 425                                        unsigned long flags);
 426#define arch_memremap_can_ram_remap arch_memremap_can_ram_remap
 427#endif
 428
 429/*
 430 * Register ISA memory and port locations for glibc iopl/inb/outb
 431 * emulation.
 432 */
 433extern void register_isa_ports(unsigned int mmio, unsigned int io,
 434                               unsigned int io_shift);
 435
 436#endif  /* __KERNEL__ */
 437#endif  /* __ASM_ARM_IO_H */
 438