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

INCLUDED FROM

DEFINITIONS

1. __raw_writew
2. __raw_readw
3. __raw_writeb
4. __raw_writel
5. __raw_readb
6. __raw_readl
7. __typesafe_io
8. pci_ioremap_set_mem_type
9. memset_io
10. memcpy_fromio
11. memcpy_toio

   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  */
  38 extern void atomic_io_modify(void __iomem *reg, u32 mask, u32 set);
  39 extern 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  */
  45 void __raw_writesb(volatile void __iomem *addr, const void *data, int bytelen);
  46 void __raw_writesw(volatile void __iomem *addr, const void *data, int wordlen);
  47 void __raw_writesl(volatile void __iomem *addr, const void *data, int longlen);
  48 
  49 void __raw_readsb(const volatile void __iomem *addr, void *data, int bytelen);
  50 void __raw_readsw(const volatile void __iomem *addr, void *data, int wordlen);
  51 void __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
  68 static 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
  75 static 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
  86 static 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
  93 static 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
 100 static 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
 110 static 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  */
 137 extern void __iomem *__arm_ioremap_caller(phys_addr_t, size_t, unsigned int,
 138         void *);
 139 extern void __iomem *__arm_ioremap_pfn(unsigned long, unsigned long, size_t, unsigned int);
 140 extern void __iomem *__arm_ioremap_exec(phys_addr_t, size_t, bool cached);
 141 extern void __iounmap(volatile void __iomem *addr);
 142 
 143 extern void __iomem * (*arch_ioremap_caller)(phys_addr_t, size_t,
 144         unsigned int, void *);
 145 extern void (*arch_iounmap)(volatile void __iomem *);
 146 
 147 /*
 148  * Bad read/write accesses...
 149  */
 150 extern void __readwrite_bug(const char *fn);
 151 
 152 /*
 153  * A typesafe __io() helper
 154  */
 155 static 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)
 177 void pci_ioremap_set_mem_type(int mem_type);
 178 #else
 179 static inline void pci_ioremap_set_mem_type(int mem_type) {}
 180 #endif
 181 
 182 extern 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
 193 void __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  */
 276 extern void _memcpy_fromio(void *, const volatile void __iomem *, size_t);
 277 extern void _memcpy_toio(volatile void __iomem *, const void *, size_t);
 278 extern 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__
 318 static 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 
 326 static 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 
 334 static 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  */
 393 void __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  */
 400 void __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  */
 407 void __iomem *ioremap_cached(resource_size_t res_cookie, size_t size);
 408 
 409 void __iomem *ioremap_wc(resource_size_t res_cookie, size_t size);
 410 #define ioremap_wc ioremap_wc
 411 #define ioremap_wt ioremap_wc
 412 
 413 void iounmap(volatile void __iomem *iomem_cookie);
 414 #define iounmap iounmap
 415 
 416 void *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
 430 extern void __iomem *ioport_map(unsigned long port, unsigned int nr);
 431 #endif
 432 #ifndef ioport_unmap
 433 #define ioport_unmap ioport_unmap
 434 extern void ioport_unmap(void __iomem *addr);
 435 #endif
 436 
 437 struct pci_dev;
 438 
 439 #define pci_iounmap pci_iounmap
 440 extern 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
 457 extern int valid_phys_addr_range(phys_addr_t addr, size_t size);
 458 extern int valid_mmap_phys_addr_range(unsigned long pfn, size_t size);
 459 extern 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  */
 466 extern 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 */