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 #include <linux/compiler.h> 16 #include <linux/kernel.h> 17 #include <linux/types.h> 18 #include <linux/irqflags.h> 19 20 #include <asm/addrspace.h> 21 #include <asm/bug.h> 22 #include <asm/byteorder.h> 23 #include <asm/cpu.h> 24 #include <asm/cpu-features.h> 25 #include <asm-generic/iomap.h> 26 #include <asm/page.h> 27 #include <asm/pgtable-bits.h> 28 #include <asm/processor.h> 29 #include <asm/string.h> 30 31 #include <ioremap.h> 32 #include <mangle-port.h> 33 34 /* 35 * Slowdown I/O port space accesses for antique hardware. 36 */ 37 #undef CONF_SLOWDOWN_IO 38 39 /* 40 * Raw operations are never swapped in software. OTOH values that raw 41 * operations are working on may or may not have been swapped by the bus 42 * hardware. An example use would be for flash memory that's used for 43 * execute in place. 44 */ 45 # define __raw_ioswabb(a, x) (x) 46 # define __raw_ioswabw(a, x) (x) 47 # define __raw_ioswabl(a, x) (x) 48 # define __raw_ioswabq(a, x) (x) 49 # define ____raw_ioswabq(a, x) (x) 50 51 /* ioswab[bwlq], __mem_ioswab[bwlq] are defined in mangle-port.h */ 52 53 #define IO_SPACE_LIMIT 0xffff 54 55 /* 56 * On MIPS I/O ports are memory mapped, so we access them using normal 57 * load/store instructions. mips_io_port_base is the virtual address to 58 * which all ports are being mapped. For sake of efficiency some code 59 * assumes that this is an address that can be loaded with a single lui 60 * instruction, so the lower 16 bits must be zero. Should be true on 61 * on any sane architecture; generic code does not use this assumption. 62 */ 63 extern const unsigned long mips_io_port_base; 64 65 /* 66 * Gcc will generate code to load the value of mips_io_port_base after each 67 * function call which may be fairly wasteful in some cases. So we don't 68 * play quite by the book. We tell gcc mips_io_port_base is a long variable 69 * which solves the code generation issue. Now we need to violate the 70 * aliasing rules a little to make initialization possible and finally we 71 * will need the barrier() to fight side effects of the aliasing chat. 72 * This trickery will eventually collapse under gcc's optimizer. Oh well. 73 */ 74 static inline void set_io_port_base(unsigned long base) 75 { 76 * (unsigned long *) &mips_io_port_base = base; 77 barrier(); 78 } 79 80 /* 81 * Thanks to James van Artsdalen for a better timing-fix than 82 * the two short jumps: using outb's to a nonexistent port seems 83 * to guarantee better timings even on fast machines. 84 * 85 * On the other hand, I'd like to be sure of a non-existent port: 86 * I feel a bit unsafe about using 0x80 (should be safe, though) 87 * 88 * Linus 89 * 90 */ 91 92 #define __SLOW_DOWN_IO \ 93 __asm__ __volatile__( \ 94 "sb\t$0,0x80(%0)" \ 95 : : "r" (mips_io_port_base)); 96 97 #ifdef CONF_SLOWDOWN_IO 98 #ifdef REALLY_SLOW_IO 99 #define SLOW_DOWN_IO { __SLOW_DOWN_IO; __SLOW_DOWN_IO; __SLOW_DOWN_IO; __SLOW_DOWN_IO; } 100 #else 101 #define SLOW_DOWN_IO __SLOW_DOWN_IO 102 #endif 103 #else 104 #define SLOW_DOWN_IO 105 #endif 106 107 /* 108 * virt_to_phys - map virtual addresses to physical 109 * @address: address to remap 110 * 111 * The returned physical address is the physical (CPU) mapping for 112 * the memory address given. It is only valid to use this function on 113 * addresses directly mapped or allocated via kmalloc. 114 * 115 * This function does not give bus mappings for DMA transfers. In 116 * almost all conceivable cases a device driver should not be using 117 * this function 118 */ 119 static inline unsigned long virt_to_phys(volatile const void *address) 120 { 121 return __pa(address); 122 } 123 124 /* 125 * phys_to_virt - map physical address to virtual 126 * @address: address to remap 127 * 128 * The returned virtual address is a current CPU mapping for 129 * the memory address given. It is only valid to use this function on 130 * addresses that have a kernel mapping 131 * 132 * This function does not handle bus mappings for DMA transfers. In 133 * almost all conceivable cases a device driver should not be using 134 * this function 135 */ 136 static inline void * phys_to_virt(unsigned long address) 137 { 138 return (void *)(address + PAGE_OFFSET - PHYS_OFFSET); 139 } 140 141 /* 142 * ISA I/O bus memory addresses are 1:1 with the physical address. 143 */ 144 static inline unsigned long isa_virt_to_bus(volatile void * address) 145 { 146 return (unsigned long)address - PAGE_OFFSET; 147 } 148 149 static inline void * isa_bus_to_virt(unsigned long address) 150 { 151 return (void *)(address + PAGE_OFFSET); 152 } 153 154 #define isa_page_to_bus page_to_phys 155 156 /* 157 * However PCI ones are not necessarily 1:1 and therefore these interfaces 158 * are forbidden in portable PCI drivers. 159 * 160 * Allow them for x86 for legacy drivers, though. 161 */ 162 #define virt_to_bus virt_to_phys 163 #define bus_to_virt phys_to_virt 164 165 /* 166 * Change "struct page" to physical address. 167 */ 168 #define page_to_phys(page) ((dma_addr_t)page_to_pfn(page) << PAGE_SHIFT) 169 170 extern void __iomem * __ioremap(phys_addr_t offset, phys_addr_t size, unsigned long flags); 171 extern void __iounmap(const volatile void __iomem *addr); 172 173 #ifndef CONFIG_PCI 174 struct pci_dev; 175 static inline void pci_iounmap(struct pci_dev *dev, void __iomem *addr) {} 176 #endif 177 178 static inline void __iomem * __ioremap_mode(phys_addr_t offset, unsigned long size, 179 unsigned long flags) 180 { 181 void __iomem *addr = plat_ioremap(offset, size, flags); 182 183 if (addr) 184 return addr; 185 186 #define __IS_LOW512(addr) (!((phys_addr_t)(addr) & (phys_addr_t) ~0x1fffffffULL)) 187 188 if (cpu_has_64bit_addresses) { 189 u64 base = UNCAC_BASE; 190 191 /* 192 * R10000 supports a 2 bit uncached attribute therefore 193 * UNCAC_BASE may not equal IO_BASE. 194 */ 195 if (flags == _CACHE_UNCACHED) 196 base = (u64) IO_BASE; 197 return (void __iomem *) (unsigned long) (base + offset); 198 } else if (__builtin_constant_p(offset) && 199 __builtin_constant_p(size) && __builtin_constant_p(flags)) { 200 phys_addr_t phys_addr, last_addr; 201 202 phys_addr = fixup_bigphys_addr(offset, size); 203 204 /* Don't allow wraparound or zero size. */ 205 last_addr = phys_addr + size - 1; 206 if (!size || last_addr < phys_addr) 207 return NULL; 208 209 /* 210 * Map uncached objects in the low 512MB of address 211 * space using KSEG1. 212 */ 213 if (__IS_LOW512(phys_addr) && __IS_LOW512(last_addr) && 214 flags == _CACHE_UNCACHED) 215 return (void __iomem *) 216 (unsigned long)CKSEG1ADDR(phys_addr); 217 } 218 219 return __ioremap(offset, size, flags); 220 221 #undef __IS_LOW512 222 } 223 224 /* 225 * ioremap - map bus memory into CPU space 226 * @offset: bus address of the memory 227 * @size: size of the resource to map 228 * 229 * ioremap performs a platform specific sequence of operations to 230 * make bus memory CPU accessible via the readb/readw/readl/writeb/ 231 * writew/writel functions and the other mmio helpers. The returned 232 * address is not guaranteed to be usable directly as a virtual 233 * address. 234 */ 235 #define ioremap(offset, size) \ 236 __ioremap_mode((offset), (size), _CACHE_UNCACHED) 237 238 /* 239 * ioremap_nocache - map bus memory into CPU space 240 * @offset: bus address of the memory 241 * @size: size of the resource to map 242 * 243 * ioremap_nocache performs a platform specific sequence of operations to 244 * make bus memory CPU accessible via the readb/readw/readl/writeb/ 245 * writew/writel functions and the other mmio helpers. The returned 246 * address is not guaranteed to be usable directly as a virtual 247 * address. 248 * 249 * This version of ioremap ensures that the memory is marked uncachable 250 * on the CPU as well as honouring existing caching rules from things like 251 * the PCI bus. Note that there are other caches and buffers on many 252 * busses. In particular driver authors should read up on PCI writes 253 * 254 * It's useful if some control registers are in such an area and 255 * write combining or read caching is not desirable: 256 */ 257 #define ioremap_nocache(offset, size) \ 258 __ioremap_mode((offset), (size), _CACHE_UNCACHED) 259 260 /* 261 * ioremap_cachable - map bus memory into CPU space 262 * @offset: bus address of the memory 263 * @size: size of the resource to map 264 * 265 * ioremap_nocache performs a platform specific sequence of operations to 266 * make bus memory CPU accessible via the readb/readw/readl/writeb/ 267 * writew/writel functions and the other mmio helpers. The returned 268 * address is not guaranteed to be usable directly as a virtual 269 * address. 270 * 271 * This version of ioremap ensures that the memory is marked cachable by 272 * the CPU. Also enables full write-combining. Useful for some 273 * memory-like regions on I/O busses. 274 */ 275 #define ioremap_cachable(offset, size) \ 276 __ioremap_mode((offset), (size), _page_cachable_default) 277 278 /* 279 * These two are MIPS specific ioremap variant. ioremap_cacheable_cow 280 * requests a cachable mapping, ioremap_uncached_accelerated requests a 281 * mapping using the uncached accelerated mode which isn't supported on 282 * all processors. 283 */ 284 #define ioremap_cacheable_cow(offset, size) \ 285 __ioremap_mode((offset), (size), _CACHE_CACHABLE_COW) 286 #define ioremap_uncached_accelerated(offset, size) \ 287 __ioremap_mode((offset), (size), _CACHE_UNCACHED_ACCELERATED) 288 289 static inline void iounmap(const volatile void __iomem *addr) 290 { 291 if (plat_iounmap(addr)) 292 return; 293 294 #define __IS_KSEG1(addr) (((unsigned long)(addr) & ~0x1fffffffUL) == CKSEG1) 295 296 if (cpu_has_64bit_addresses || 297 (__builtin_constant_p(addr) && __IS_KSEG1(addr))) 298 return; 299 300 __iounmap(addr); 301 302 #undef __IS_KSEG1 303 } 304 305 #ifdef CONFIG_CPU_CAVIUM_OCTEON 306 #define war_octeon_io_reorder_wmb() wmb() 307 #else 308 #define war_octeon_io_reorder_wmb() do { } while (0) 309 #endif 310 311 #define __BUILD_MEMORY_SINGLE(pfx, bwlq, type, irq) \ 312 \ 313 static inline void pfx##write##bwlq(type val, \ 314 volatile void __iomem *mem) \ 315 { \ 316 volatile type *__mem; \ 317 type __val; \ 318 \ 319 war_octeon_io_reorder_wmb(); \ 320 \ 321 __mem = (void *)__swizzle_addr_##bwlq((unsigned long)(mem)); \ 322 \ 323 __val = pfx##ioswab##bwlq(__mem, val); \ 324 \ 325 if (sizeof(type) != sizeof(u64) || sizeof(u64) == sizeof(long)) \ 326 *__mem = __val; \ 327 else if (cpu_has_64bits) { \ 328 unsigned long __flags; \ 329 type __tmp; \ 330 \ 331 if (irq) \ 332 local_irq_save(__flags); \ 333 __asm__ __volatile__( \ 334 ".set arch=r4000" "\t\t# __writeq""\n\t" \ 335 "dsll32 %L0, %L0, 0" "\n\t" \ 336 "dsrl32 %L0, %L0, 0" "\n\t" \ 337 "dsll32 %M0, %M0, 0" "\n\t" \ 338 "or %L0, %L0, %M0" "\n\t" \ 339 "sd %L0, %2" "\n\t" \ 340 ".set mips0" "\n" \ 341 : "=r" (__tmp) \ 342 : "0" (__val), "m" (*__mem)); \ 343 if (irq) \ 344 local_irq_restore(__flags); \ 345 } else \ 346 BUG(); \ 347 } \ 348 \ 349 static inline type pfx##read##bwlq(const volatile void __iomem *mem) \ 350 { \ 351 volatile type *__mem; \ 352 type __val; \ 353 \ 354 __mem = (void *)__swizzle_addr_##bwlq((unsigned long)(mem)); \ 355 \ 356 if (sizeof(type) != sizeof(u64) || sizeof(u64) == sizeof(long)) \ 357 __val = *__mem; \ 358 else if (cpu_has_64bits) { \ 359 unsigned long __flags; \ 360 \ 361 if (irq) \ 362 local_irq_save(__flags); \ 363 __asm__ __volatile__( \ 364 ".set arch=r4000" "\t\t# __readq" "\n\t" \ 365 "ld %L0, %1" "\n\t" \ 366 "dsra32 %M0, %L0, 0" "\n\t" \ 367 "sll %L0, %L0, 0" "\n\t" \ 368 ".set mips0" "\n" \ 369 : "=r" (__val) \ 370 : "m" (*__mem)); \ 371 if (irq) \ 372 local_irq_restore(__flags); \ 373 } else { \ 374 __val = 0; \ 375 BUG(); \ 376 } \ 377 \ 378 return pfx##ioswab##bwlq(__mem, __val); \ 379 } 380 381 #define __BUILD_IOPORT_SINGLE(pfx, bwlq, type, p, slow) \ 382 \ 383 static inline void pfx##out##bwlq##p(type val, unsigned long port) \ 384 { \ 385 volatile type *__addr; \ 386 type __val; \ 387 \ 388 war_octeon_io_reorder_wmb(); \ 389 \ 390 __addr = (void *)__swizzle_addr_##bwlq(mips_io_port_base + port); \ 391 \ 392 __val = pfx##ioswab##bwlq(__addr, val); \ 393 \ 394 /* Really, we want this to be atomic */ \ 395 BUILD_BUG_ON(sizeof(type) > sizeof(unsigned long)); \ 396 \ 397 *__addr = __val; \ 398 slow; \ 399 } \ 400 \ 401 static inline type pfx##in##bwlq##p(unsigned long port) \ 402 { \ 403 volatile type *__addr; \ 404 type __val; \ 405 \ 406 __addr = (void *)__swizzle_addr_##bwlq(mips_io_port_base + port); \ 407 \ 408 BUILD_BUG_ON(sizeof(type) > sizeof(unsigned long)); \ 409 \ 410 __val = *__addr; \ 411 slow; \ 412 \ 413 return pfx##ioswab##bwlq(__addr, __val); \ 414 } 415 416 #define __BUILD_MEMORY_PFX(bus, bwlq, type) \ 417 \ 418 __BUILD_MEMORY_SINGLE(bus, bwlq, type, 1) 419 420 #define BUILDIO_MEM(bwlq, type) \ 421 \ 422 __BUILD_MEMORY_PFX(__raw_, bwlq, type) \ 423 __BUILD_MEMORY_PFX(, bwlq, type) \ 424 __BUILD_MEMORY_PFX(__mem_, bwlq, type) \ 425 426 BUILDIO_MEM(b, u8) 427 BUILDIO_MEM(w, u16) 428 BUILDIO_MEM(l, u32) 429 BUILDIO_MEM(q, u64) 430 431 #define __BUILD_IOPORT_PFX(bus, bwlq, type) \ 432 __BUILD_IOPORT_SINGLE(bus, bwlq, type, ,) \ 433 __BUILD_IOPORT_SINGLE(bus, bwlq, type, _p, SLOW_DOWN_IO) 434 435 #define BUILDIO_IOPORT(bwlq, type) \ 436 __BUILD_IOPORT_PFX(, bwlq, type) \ 437 __BUILD_IOPORT_PFX(__mem_, bwlq, type) 438 439 BUILDIO_IOPORT(b, u8) 440 BUILDIO_IOPORT(w, u16) 441 BUILDIO_IOPORT(l, u32) 442 #ifdef CONFIG_64BIT 443 BUILDIO_IOPORT(q, u64) 444 #endif 445 446 #define __BUILDIO(bwlq, type) \ 447 \ 448 __BUILD_MEMORY_SINGLE(____raw_, bwlq, type, 0) 449 450 __BUILDIO(q, u64) 451 452 #define readb_relaxed readb 453 #define readw_relaxed readw 454 #define readl_relaxed readl 455 #define readq_relaxed readq 456 457 #define writeb_relaxed writeb 458 #define writew_relaxed writew 459 #define writel_relaxed writel 460 #define writeq_relaxed writeq 461 462 #define readb_be(addr) \ 463 __raw_readb((__force unsigned *)(addr)) 464 #define readw_be(addr) \ 465 be16_to_cpu(__raw_readw((__force unsigned *)(addr))) 466 #define readl_be(addr) \ 467 be32_to_cpu(__raw_readl((__force unsigned *)(addr))) 468 #define readq_be(addr) \ 469 be64_to_cpu(__raw_readq((__force unsigned *)(addr))) 470 471 #define writeb_be(val, addr) \ 472 __raw_writeb((val), (__force unsigned *)(addr)) 473 #define writew_be(val, addr) \ 474 __raw_writew(cpu_to_be16((val)), (__force unsigned *)(addr)) 475 #define writel_be(val, addr) \ 476 __raw_writel(cpu_to_be32((val)), (__force unsigned *)(addr)) 477 #define writeq_be(val, addr) \ 478 __raw_writeq(cpu_to_be64((val)), (__force unsigned *)(addr)) 479 480 /* 481 * Some code tests for these symbols 482 */ 483 #define readq readq 484 #define writeq writeq 485 486 #define __BUILD_MEMORY_STRING(bwlq, type) \ 487 \ 488 static inline void writes##bwlq(volatile void __iomem *mem, \ 489 const void *addr, unsigned int count) \ 490 { \ 491 const volatile type *__addr = addr; \ 492 \ 493 while (count--) { \ 494 __mem_write##bwlq(*__addr, mem); \ 495 __addr++; \ 496 } \ 497 } \ 498 \ 499 static inline void reads##bwlq(volatile void __iomem *mem, void *addr, \ 500 unsigned int count) \ 501 { \ 502 volatile type *__addr = addr; \ 503 \ 504 while (count--) { \ 505 *__addr = __mem_read##bwlq(mem); \ 506 __addr++; \ 507 } \ 508 } 509 510 #define __BUILD_IOPORT_STRING(bwlq, type) \ 511 \ 512 static inline void outs##bwlq(unsigned long port, const void *addr, \ 513 unsigned int count) \ 514 { \ 515 const volatile type *__addr = addr; \ 516 \ 517 while (count--) { \ 518 __mem_out##bwlq(*__addr, port); \ 519 __addr++; \ 520 } \ 521 } \ 522 \ 523 static inline void ins##bwlq(unsigned long port, void *addr, \ 524 unsigned int count) \ 525 { \ 526 volatile type *__addr = addr; \ 527 \ 528 while (count--) { \ 529 *__addr = __mem_in##bwlq(port); \ 530 __addr++; \ 531 } \ 532 } 533 534 #define BUILDSTRING(bwlq, type) \ 535 \ 536 __BUILD_MEMORY_STRING(bwlq, type) \ 537 __BUILD_IOPORT_STRING(bwlq, type) 538 539 BUILDSTRING(b, u8) 540 BUILDSTRING(w, u16) 541 BUILDSTRING(l, u32) 542 #ifdef CONFIG_64BIT 543 BUILDSTRING(q, u64) 544 #endif 545 546 547 #ifdef CONFIG_CPU_CAVIUM_OCTEON 548 #define mmiowb() wmb() 549 #else 550 /* Depends on MIPS II instruction set */ 551 #define mmiowb() asm volatile ("sync" ::: "memory") 552 #endif 553 554 static inline void memset_io(volatile void __iomem *addr, unsigned char val, int count) 555 { 556 memset((void __force *) addr, val, count); 557 } 558 static inline void memcpy_fromio(void *dst, const volatile void __iomem *src, int count) 559 { 560 memcpy(dst, (void __force *) src, count); 561 } 562 static inline void memcpy_toio(volatile void __iomem *dst, const void *src, int count) 563 { 564 memcpy((void __force *) dst, src, count); 565 } 566 567 /* 568 * The caches on some architectures aren't dma-coherent and have need to 569 * handle this in software. There are three types of operations that 570 * can be applied to dma buffers. 571 * 572 * - dma_cache_wback_inv(start, size) makes caches and coherent by 573 * writing the content of the caches back to memory, if necessary. 574 * The function also invalidates the affected part of the caches as 575 * necessary before DMA transfers from outside to memory. 576 * - dma_cache_wback(start, size) makes caches and coherent by 577 * writing the content of the caches back to memory, if necessary. 578 * The function also invalidates the affected part of the caches as 579 * necessary before DMA transfers from outside to memory. 580 * - dma_cache_inv(start, size) invalidates the affected parts of the 581 * caches. Dirty lines of the caches may be written back or simply 582 * be discarded. This operation is necessary before dma operations 583 * to the memory. 584 * 585 * This API used to be exported; it now is for arch code internal use only. 586 */ 587 #if defined(CONFIG_DMA_NONCOHERENT) || defined(CONFIG_DMA_MAYBE_COHERENT) 588 589 extern void (*_dma_cache_wback_inv)(unsigned long start, unsigned long size); 590 extern void (*_dma_cache_wback)(unsigned long start, unsigned long size); 591 extern void (*_dma_cache_inv)(unsigned long start, unsigned long size); 592 593 #define dma_cache_wback_inv(start, size) _dma_cache_wback_inv(start, size) 594 #define dma_cache_wback(start, size) _dma_cache_wback(start, size) 595 #define dma_cache_inv(start, size) _dma_cache_inv(start, size) 596 597 #else /* Sane hardware */ 598 599 #define dma_cache_wback_inv(start,size) \ 600 do { (void) (start); (void) (size); } while (0) 601 #define dma_cache_wback(start,size) \ 602 do { (void) (start); (void) (size); } while (0) 603 #define dma_cache_inv(start,size) \ 604 do { (void) (start); (void) (size); } while (0) 605 606 #endif /* CONFIG_DMA_NONCOHERENT || CONFIG_DMA_MAYBE_COHERENT */ 607 608 /* 609 * Read a 32-bit register that requires a 64-bit read cycle on the bus. 610 * Avoid interrupt mucking, just adjust the address for 4-byte access. 611 * Assume the addresses are 8-byte aligned. 612 */ 613 #ifdef __MIPSEB__ 614 #define __CSR_32_ADJUST 4 615 #else 616 #define __CSR_32_ADJUST 0 617 #endif 618 619 #define csr_out32(v, a) (*(volatile u32 *)((unsigned long)(a) + __CSR_32_ADJUST) = (v)) 620 #define csr_in32(a) (*(volatile u32 *)((unsigned long)(a) + __CSR_32_ADJUST)) 621 622 /* 623 * Convert a physical pointer to a virtual kernel pointer for /dev/mem 624 * access 625 */ 626 #define xlate_dev_mem_ptr(p) __va(p) 627 628 /* 629 * Convert a virtual cached pointer to an uncached pointer 630 */ 631 #define xlate_dev_kmem_ptr(p) p 632 633 #endif /* _ASM_IO_H */ 634