linux/arch/mips/include/asm/io.h
<<
>>
Prefs
   1/*
   2 * This file is subject to the terms and conditions of the GNU General Public
   3 * License.  See the file "COPYING" in the main directory of this archive
   4 * for more details.
   5 *
   6 * Copyright (C) 1994, 1995 Waldorf GmbH
   7 * Copyright (C) 1994 - 2000, 06 Ralf Baechle
   8 * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
   9 * Copyright (C) 2004, 2005  MIPS Technologies, Inc.  All rights reserved.
  10 *      Author: Maciej W. Rozycki <macro@mips.com>
  11 */
  12#ifndef _ASM_IO_H
  13#define _ASM_IO_H
  14
  15#define ARCH_HAS_IOREMAP_WC
  16
  17#include <linux/compiler.h>
  18#include <linux/kernel.h>
  19#include <linux/types.h>
  20#include <linux/irqflags.h>
  21
  22#include <asm/addrspace.h>
  23#include <asm/barrier.h>
  24#include <asm/bug.h>
  25#include <asm/byteorder.h>
  26#include <asm/cpu.h>
  27#include <asm/cpu-features.h>
  28#include <asm-generic/iomap.h>
  29#include <asm/page.h>
  30#include <asm/pgtable-bits.h>
  31#include <asm/processor.h>
  32#include <asm/string.h>
  33#include <mangle-port.h>
  34
  35/*
  36 * Raw operations are never swapped in software.  OTOH values that raw
  37 * operations are working on may or may not have been swapped by the bus
  38 * hardware.  An example use would be for flash memory that's used for
  39 * execute in place.
  40 */
  41# define __raw_ioswabb(a, x)    (x)
  42# define __raw_ioswabw(a, x)    (x)
  43# define __raw_ioswabl(a, x)    (x)
  44# define __raw_ioswabq(a, x)    (x)
  45# define ____raw_ioswabq(a, x)  (x)
  46
  47# define __relaxed_ioswabb ioswabb
  48# define __relaxed_ioswabw ioswabw
  49# define __relaxed_ioswabl ioswabl
  50# define __relaxed_ioswabq ioswabq
  51
  52/* ioswab[bwlq], __mem_ioswab[bwlq] are defined in mangle-port.h */
  53
  54/*
  55 * On MIPS I/O ports are memory mapped, so we access them using normal
  56 * load/store instructions. mips_io_port_base is the virtual address to
  57 * which all ports are being mapped.  For sake of efficiency some code
  58 * assumes that this is an address that can be loaded with a single lui
  59 * instruction, so the lower 16 bits must be zero.  Should be true on
  60 * any sane architecture; generic code does not use this assumption.
  61 */
  62extern unsigned long mips_io_port_base;
  63
  64static inline void set_io_port_base(unsigned long base)
  65{
  66        mips_io_port_base = base;
  67}
  68
  69/*
  70 * Provide the necessary definitions for generic iomap. We make use of
  71 * mips_io_port_base for iomap(), but we don't reserve any low addresses for
  72 * use with I/O ports.
  73 */
  74
  75#define HAVE_ARCH_PIO_SIZE
  76#define PIO_OFFSET      mips_io_port_base
  77#define PIO_MASK        IO_SPACE_LIMIT
  78#define PIO_RESERVED    0x0UL
  79
  80/*
  81 * Enforce in-order execution of data I/O.  In the MIPS architecture
  82 * these are equivalent to corresponding platform-specific memory
  83 * barriers defined in <asm/barrier.h>.  API pinched from PowerPC,
  84 * with sync additionally defined.
  85 */
  86#define iobarrier_rw() mb()
  87#define iobarrier_r() rmb()
  88#define iobarrier_w() wmb()
  89#define iobarrier_sync() iob()
  90
  91/*
  92 *     virt_to_phys    -       map virtual addresses to physical
  93 *     @address: address to remap
  94 *
  95 *     The returned physical address is the physical (CPU) mapping for
  96 *     the memory address given. It is only valid to use this function on
  97 *     addresses directly mapped or allocated via kmalloc.
  98 *
  99 *     This function does not give bus mappings for DMA transfers. In
 100 *     almost all conceivable cases a device driver should not be using
 101 *     this function
 102 */
 103static inline unsigned long virt_to_phys(volatile const void *address)
 104{
 105        return __pa(address);
 106}
 107
 108/*
 109 *     phys_to_virt    -       map physical address to virtual
 110 *     @address: address to remap
 111 *
 112 *     The returned virtual address is a current CPU mapping for
 113 *     the memory address given. It is only valid to use this function on
 114 *     addresses that have a kernel mapping
 115 *
 116 *     This function does not handle bus mappings for DMA transfers. In
 117 *     almost all conceivable cases a device driver should not be using
 118 *     this function
 119 */
 120static inline void * phys_to_virt(unsigned long address)
 121{
 122        return (void *)(address + PAGE_OFFSET - PHYS_OFFSET);
 123}
 124
 125/*
 126 * ISA I/O bus memory addresses are 1:1 with the physical address.
 127 */
 128static inline unsigned long isa_virt_to_bus(volatile void *address)
 129{
 130        return virt_to_phys(address);
 131}
 132
 133static inline void *isa_bus_to_virt(unsigned long address)
 134{
 135        return phys_to_virt(address);
 136}
 137
 138/*
 139 * However PCI ones are not necessarily 1:1 and therefore these interfaces
 140 * are forbidden in portable PCI drivers.
 141 *
 142 * Allow them for x86 for legacy drivers, though.
 143 */
 144#define virt_to_bus virt_to_phys
 145#define bus_to_virt phys_to_virt
 146
 147/*
 148 * Change "struct page" to physical address.
 149 */
 150#define page_to_phys(page)      ((dma_addr_t)page_to_pfn(page) << PAGE_SHIFT)
 151
 152void __iomem *ioremap_prot(phys_addr_t offset, unsigned long size,
 153                unsigned long prot_val);
 154void iounmap(const volatile void __iomem *addr);
 155
 156/*
 157 * ioremap     -   map bus memory into CPU space
 158 * @offset:    bus address of the memory
 159 * @size:      size of the resource to map
 160 *
 161 * ioremap performs a platform specific sequence of operations to
 162 * make bus memory CPU accessible via the readb/readw/readl/writeb/
 163 * writew/writel functions and the other mmio helpers. The returned
 164 * address is not guaranteed to be usable directly as a virtual
 165 * address.
 166 */
 167#define ioremap(offset, size)                                           \
 168        ioremap_prot((offset), (size), _CACHE_UNCACHED)
 169#define ioremap_uc              ioremap
 170
 171/*
 172 * ioremap_cache -      map bus memory into CPU space
 173 * @offset:         bus address of the memory
 174 * @size:           size of the resource to map
 175 *
 176 * ioremap_cache performs a platform specific sequence of operations to
 177 * make bus memory CPU accessible via the readb/readw/readl/writeb/
 178 * writew/writel functions and the other mmio helpers. The returned
 179 * address is not guaranteed to be usable directly as a virtual
 180 * address.
 181 *
 182 * This version of ioremap ensures that the memory is marked cachable by
 183 * the CPU.  Also enables full write-combining.  Useful for some
 184 * memory-like regions on I/O busses.
 185 */
 186#define ioremap_cache(offset, size)                                     \
 187        ioremap_prot((offset), (size), _page_cachable_default)
 188
 189/*
 190 * ioremap_wc     -   map bus memory into CPU space
 191 * @offset:    bus address of the memory
 192 * @size:      size of the resource to map
 193 *
 194 * ioremap_wc performs a platform specific sequence of operations to
 195 * make bus memory CPU accessible via the readb/readw/readl/writeb/
 196 * writew/writel functions and the other mmio helpers. The returned
 197 * address is not guaranteed to be usable directly as a virtual
 198 * address.
 199 *
 200 * This version of ioremap ensures that the memory is marked uncachable
 201 * but accelerated by means of write-combining feature. It is specifically
 202 * useful for PCIe prefetchable windows, which may vastly improve a
 203 * communications performance. If it was determined on boot stage, what
 204 * CPU CCA doesn't support UCA, the method shall fall-back to the
 205 * _CACHE_UNCACHED option (see cpu_probe() method).
 206 */
 207#define ioremap_wc(offset, size)                                        \
 208        ioremap_prot((offset), (size), boot_cpu_data.writecombine)
 209
 210#if defined(CONFIG_CPU_CAVIUM_OCTEON) || defined(CONFIG_CPU_LOONGSON64)
 211#define war_io_reorder_wmb()            wmb()
 212#else
 213#define war_io_reorder_wmb()            barrier()
 214#endif
 215
 216#define __BUILD_MEMORY_SINGLE(pfx, bwlq, type, barrier, relax, irq)     \
 217                                                                        \
 218static inline void pfx##write##bwlq(type val,                           \
 219                                    volatile void __iomem *mem)         \
 220{                                                                       \
 221        volatile type *__mem;                                           \
 222        type __val;                                                     \
 223                                                                        \
 224        if (barrier)                                                    \
 225                iobarrier_rw();                                         \
 226        else                                                            \
 227                war_io_reorder_wmb();                                   \
 228                                                                        \
 229        __mem = (void *)__swizzle_addr_##bwlq((unsigned long)(mem));    \
 230                                                                        \
 231        __val = pfx##ioswab##bwlq(__mem, val);                          \
 232                                                                        \
 233        if (sizeof(type) != sizeof(u64) || sizeof(u64) == sizeof(long)) \
 234                *__mem = __val;                                         \
 235        else if (cpu_has_64bits) {                                      \
 236                unsigned long __flags;                                  \
 237                type __tmp;                                             \
 238                                                                        \
 239                if (irq)                                                \
 240                        local_irq_save(__flags);                        \
 241                __asm__ __volatile__(                                   \
 242                        ".set   push"           "\t\t# __writeq""\n\t"  \
 243                        ".set   arch=r4000"                     "\n\t"  \
 244                        "dsll32 %L0, %L0, 0"                    "\n\t"  \
 245                        "dsrl32 %L0, %L0, 0"                    "\n\t"  \
 246                        "dsll32 %M0, %M0, 0"                    "\n\t"  \
 247                        "or     %L0, %L0, %M0"                  "\n\t"  \
 248                        "sd     %L0, %2"                        "\n\t"  \
 249                        ".set   pop"                            "\n"    \
 250                        : "=r" (__tmp)                                  \
 251                        : "0" (__val), "m" (*__mem));                   \
 252                if (irq)                                                \
 253                        local_irq_restore(__flags);                     \
 254        } else                                                          \
 255                BUG();                                                  \
 256}                                                                       \
 257                                                                        \
 258static inline type pfx##read##bwlq(const volatile void __iomem *mem)    \
 259{                                                                       \
 260        volatile type *__mem;                                           \
 261        type __val;                                                     \
 262                                                                        \
 263        __mem = (void *)__swizzle_addr_##bwlq((unsigned long)(mem));    \
 264                                                                        \
 265        if (barrier)                                                    \
 266                iobarrier_rw();                                         \
 267                                                                        \
 268        if (sizeof(type) != sizeof(u64) || sizeof(u64) == sizeof(long)) \
 269                __val = *__mem;                                         \
 270        else if (cpu_has_64bits) {                                      \
 271                unsigned long __flags;                                  \
 272                                                                        \
 273                if (irq)                                                \
 274                        local_irq_save(__flags);                        \
 275                __asm__ __volatile__(                                   \
 276                        ".set   push"           "\t\t# __readq" "\n\t"  \
 277                        ".set   arch=r4000"                     "\n\t"  \
 278                        "ld     %L0, %1"                        "\n\t"  \
 279                        "dsra32 %M0, %L0, 0"                    "\n\t"  \
 280                        "sll    %L0, %L0, 0"                    "\n\t"  \
 281                        ".set   pop"                            "\n"    \
 282                        : "=r" (__val)                                  \
 283                        : "m" (*__mem));                                \
 284                if (irq)                                                \
 285                        local_irq_restore(__flags);                     \
 286        } else {                                                        \
 287                __val = 0;                                              \
 288                BUG();                                                  \
 289        }                                                               \
 290                                                                        \
 291        /* prevent prefetching of coherent DMA data prematurely */      \
 292        if (!relax)                                                     \
 293                rmb();                                                  \
 294        return pfx##ioswab##bwlq(__mem, __val);                         \
 295}
 296
 297#define __BUILD_IOPORT_SINGLE(pfx, bwlq, type, barrier, relax, p)       \
 298                                                                        \
 299static inline void pfx##out##bwlq##p(type val, unsigned long port)      \
 300{                                                                       \
 301        volatile type *__addr;                                          \
 302        type __val;                                                     \
 303                                                                        \
 304        if (barrier)                                                    \
 305                iobarrier_rw();                                         \
 306        else                                                            \
 307                war_io_reorder_wmb();                                   \
 308                                                                        \
 309        __addr = (void *)__swizzle_addr_##bwlq(mips_io_port_base + port); \
 310                                                                        \
 311        __val = pfx##ioswab##bwlq(__addr, val);                         \
 312                                                                        \
 313        /* Really, we want this to be atomic */                         \
 314        BUILD_BUG_ON(sizeof(type) > sizeof(unsigned long));             \
 315                                                                        \
 316        *__addr = __val;                                                \
 317}                                                                       \
 318                                                                        \
 319static inline type pfx##in##bwlq##p(unsigned long port)                 \
 320{                                                                       \
 321        volatile type *__addr;                                          \
 322        type __val;                                                     \
 323                                                                        \
 324        __addr = (void *)__swizzle_addr_##bwlq(mips_io_port_base + port); \
 325                                                                        \
 326        BUILD_BUG_ON(sizeof(type) > sizeof(unsigned long));             \
 327                                                                        \
 328        if (barrier)                                                    \
 329                iobarrier_rw();                                         \
 330                                                                        \
 331        __val = *__addr;                                                \
 332                                                                        \
 333        /* prevent prefetching of coherent DMA data prematurely */      \
 334        if (!relax)                                                     \
 335                rmb();                                                  \
 336        return pfx##ioswab##bwlq(__addr, __val);                        \
 337}
 338
 339#define __BUILD_MEMORY_PFX(bus, bwlq, type, relax)                      \
 340                                                                        \
 341__BUILD_MEMORY_SINGLE(bus, bwlq, type, 1, relax, 1)
 342
 343#define BUILDIO_MEM(bwlq, type)                                         \
 344                                                                        \
 345__BUILD_MEMORY_PFX(__raw_, bwlq, type, 0)                               \
 346__BUILD_MEMORY_PFX(__relaxed_, bwlq, type, 1)                           \
 347__BUILD_MEMORY_PFX(__mem_, bwlq, type, 0)                               \
 348__BUILD_MEMORY_PFX(, bwlq, type, 0)
 349
 350BUILDIO_MEM(b, u8)
 351BUILDIO_MEM(w, u16)
 352BUILDIO_MEM(l, u32)
 353#ifdef CONFIG_64BIT
 354BUILDIO_MEM(q, u64)
 355#else
 356__BUILD_MEMORY_PFX(__raw_, q, u64, 0)
 357__BUILD_MEMORY_PFX(__mem_, q, u64, 0)
 358#endif
 359
 360#define __BUILD_IOPORT_PFX(bus, bwlq, type)                             \
 361        __BUILD_IOPORT_SINGLE(bus, bwlq, type, 1, 0,)                   \
 362        __BUILD_IOPORT_SINGLE(bus, bwlq, type, 1, 0, _p)
 363
 364#define BUILDIO_IOPORT(bwlq, type)                                      \
 365        __BUILD_IOPORT_PFX(, bwlq, type)                                \
 366        __BUILD_IOPORT_PFX(__mem_, bwlq, type)
 367
 368BUILDIO_IOPORT(b, u8)
 369BUILDIO_IOPORT(w, u16)
 370BUILDIO_IOPORT(l, u32)
 371#ifdef CONFIG_64BIT
 372BUILDIO_IOPORT(q, u64)
 373#endif
 374
 375#define __BUILDIO(bwlq, type)                                           \
 376                                                                        \
 377__BUILD_MEMORY_SINGLE(____raw_, bwlq, type, 1, 0, 0)
 378
 379__BUILDIO(q, u64)
 380
 381#define readb_relaxed                   __relaxed_readb
 382#define readw_relaxed                   __relaxed_readw
 383#define readl_relaxed                   __relaxed_readl
 384#ifdef CONFIG_64BIT
 385#define readq_relaxed                   __relaxed_readq
 386#endif
 387
 388#define writeb_relaxed                  __relaxed_writeb
 389#define writew_relaxed                  __relaxed_writew
 390#define writel_relaxed                  __relaxed_writel
 391#ifdef CONFIG_64BIT
 392#define writeq_relaxed                  __relaxed_writeq
 393#endif
 394
 395#define readb_be(addr)                                                  \
 396        __raw_readb((__force unsigned *)(addr))
 397#define readw_be(addr)                                                  \
 398        be16_to_cpu(__raw_readw((__force unsigned *)(addr)))
 399#define readl_be(addr)                                                  \
 400        be32_to_cpu(__raw_readl((__force unsigned *)(addr)))
 401#define readq_be(addr)                                                  \
 402        be64_to_cpu(__raw_readq((__force unsigned *)(addr)))
 403
 404#define writeb_be(val, addr)                                            \
 405        __raw_writeb((val), (__force unsigned *)(addr))
 406#define writew_be(val, addr)                                            \
 407        __raw_writew(cpu_to_be16((val)), (__force unsigned *)(addr))
 408#define writel_be(val, addr)                                            \
 409        __raw_writel(cpu_to_be32((val)), (__force unsigned *)(addr))
 410#define writeq_be(val, addr)                                            \
 411        __raw_writeq(cpu_to_be64((val)), (__force unsigned *)(addr))
 412
 413/*
 414 * Some code tests for these symbols
 415 */
 416#ifdef CONFIG_64BIT
 417#define readq                           readq
 418#define writeq                          writeq
 419#endif
 420
 421#define __BUILD_MEMORY_STRING(bwlq, type)                               \
 422                                                                        \
 423static inline void writes##bwlq(volatile void __iomem *mem,             \
 424                                const void *addr, unsigned int count)   \
 425{                                                                       \
 426        const volatile type *__addr = addr;                             \
 427                                                                        \
 428        while (count--) {                                               \
 429                __mem_write##bwlq(*__addr, mem);                        \
 430                __addr++;                                               \
 431        }                                                               \
 432}                                                                       \
 433                                                                        \
 434static inline void reads##bwlq(volatile void __iomem *mem, void *addr,  \
 435                               unsigned int count)                      \
 436{                                                                       \
 437        volatile type *__addr = addr;                                   \
 438                                                                        \
 439        while (count--) {                                               \
 440                *__addr = __mem_read##bwlq(mem);                        \
 441                __addr++;                                               \
 442        }                                                               \
 443}
 444
 445#define __BUILD_IOPORT_STRING(bwlq, type)                               \
 446                                                                        \
 447static inline void outs##bwlq(unsigned long port, const void *addr,     \
 448                              unsigned int count)                       \
 449{                                                                       \
 450        const volatile type *__addr = addr;                             \
 451                                                                        \
 452        while (count--) {                                               \
 453                __mem_out##bwlq(*__addr, port);                         \
 454                __addr++;                                               \
 455        }                                                               \
 456}                                                                       \
 457                                                                        \
 458static inline void ins##bwlq(unsigned long port, void *addr,            \
 459                             unsigned int count)                        \
 460{                                                                       \
 461        volatile type *__addr = addr;                                   \
 462                                                                        \
 463        while (count--) {                                               \
 464                *__addr = __mem_in##bwlq(port);                         \
 465                __addr++;                                               \
 466        }                                                               \
 467}
 468
 469#define BUILDSTRING(bwlq, type)                                         \
 470                                                                        \
 471__BUILD_MEMORY_STRING(bwlq, type)                                       \
 472__BUILD_IOPORT_STRING(bwlq, type)
 473
 474BUILDSTRING(b, u8)
 475BUILDSTRING(w, u16)
 476BUILDSTRING(l, u32)
 477#ifdef CONFIG_64BIT
 478BUILDSTRING(q, u64)
 479#endif
 480
 481static inline void memset_io(volatile void __iomem *addr, unsigned char val, int count)
 482{
 483        memset((void __force *) addr, val, count);
 484}
 485static inline void memcpy_fromio(void *dst, const volatile void __iomem *src, int count)
 486{
 487        memcpy(dst, (void __force *) src, count);
 488}
 489static inline void memcpy_toio(volatile void __iomem *dst, const void *src, int count)
 490{
 491        memcpy((void __force *) dst, src, count);
 492}
 493
 494/*
 495 * The caches on some architectures aren't dma-coherent and have need to
 496 * handle this in software.  There are three types of operations that
 497 * can be applied to dma buffers.
 498 *
 499 *  - dma_cache_wback_inv(start, size) makes caches and coherent by
 500 *    writing the content of the caches back to memory, if necessary.
 501 *    The function also invalidates the affected part of the caches as
 502 *    necessary before DMA transfers from outside to memory.
 503 *  - dma_cache_wback(start, size) makes caches and coherent by
 504 *    writing the content of the caches back to memory, if necessary.
 505 *    The function also invalidates the affected part of the caches as
 506 *    necessary before DMA transfers from outside to memory.
 507 *  - dma_cache_inv(start, size) invalidates the affected parts of the
 508 *    caches.  Dirty lines of the caches may be written back or simply
 509 *    be discarded.  This operation is necessary before dma operations
 510 *    to the memory.
 511 *
 512 * This API used to be exported; it now is for arch code internal use only.
 513 */
 514#ifdef CONFIG_DMA_NONCOHERENT
 515
 516extern void (*_dma_cache_wback_inv)(unsigned long start, unsigned long size);
 517extern void (*_dma_cache_wback)(unsigned long start, unsigned long size);
 518extern void (*_dma_cache_inv)(unsigned long start, unsigned long size);
 519
 520#define dma_cache_wback_inv(start, size)        _dma_cache_wback_inv(start, size)
 521#define dma_cache_wback(start, size)            _dma_cache_wback(start, size)
 522#define dma_cache_inv(start, size)              _dma_cache_inv(start, size)
 523
 524#else /* Sane hardware */
 525
 526#define dma_cache_wback_inv(start,size) \
 527        do { (void) (start); (void) (size); } while (0)
 528#define dma_cache_wback(start,size)     \
 529        do { (void) (start); (void) (size); } while (0)
 530#define dma_cache_inv(start,size)       \
 531        do { (void) (start); (void) (size); } while (0)
 532
 533#endif /* CONFIG_DMA_NONCOHERENT */
 534
 535/*
 536 * Read a 32-bit register that requires a 64-bit read cycle on the bus.
 537 * Avoid interrupt mucking, just adjust the address for 4-byte access.
 538 * Assume the addresses are 8-byte aligned.
 539 */
 540#ifdef __MIPSEB__
 541#define __CSR_32_ADJUST 4
 542#else
 543#define __CSR_32_ADJUST 0
 544#endif
 545
 546#define csr_out32(v, a) (*(volatile u32 *)((unsigned long)(a) + __CSR_32_ADJUST) = (v))
 547#define csr_in32(a)    (*(volatile u32 *)((unsigned long)(a) + __CSR_32_ADJUST))
 548
 549/*
 550 * Convert a physical pointer to a virtual kernel pointer for /dev/mem
 551 * access
 552 */
 553#define xlate_dev_mem_ptr(p)    __va(p)
 554
 555/*
 556 * Convert a virtual cached pointer to an uncached pointer
 557 */
 558#define xlate_dev_kmem_ptr(p)   p
 559
 560void __ioread64_copy(void *to, const void __iomem *from, size_t count);
 561
 562#endif /* _ASM_IO_H */
 563