Linux 2.6.21.1
[linux/fpc-iii.git] / include / asm-mips / io.h
blob92ec2618560c984355e653d33d5dc935e5e1488c
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.
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>
12 #ifndef _ASM_IO_H
13 #define _ASM_IO_H
15 #include <linux/compiler.h>
16 #include <linux/kernel.h>
17 #include <linux/types.h>
19 #include <asm/addrspace.h>
20 #include <asm/byteorder.h>
21 #include <asm/cpu.h>
22 #include <asm/cpu-features.h>
23 #include <asm-generic/iomap.h>
24 #include <asm/page.h>
25 #include <asm/pgtable-bits.h>
26 #include <asm/processor.h>
27 #include <asm/string.h>
29 #include <ioremap.h>
30 #include <mangle-port.h>
33 * Slowdown I/O port space accesses for antique hardware.
35 #undef CONF_SLOWDOWN_IO
38 * Raw operations are never swapped in software. OTOH values that raw
39 * operations are working on may or may not have been swapped by the bus
40 * hardware. An example use would be for flash memory that's used for
41 * execute in place.
43 # define __raw_ioswabb(a,x) (x)
44 # define __raw_ioswabw(a,x) (x)
45 # define __raw_ioswabl(a,x) (x)
46 # define __raw_ioswabq(a,x) (x)
47 # define ____raw_ioswabq(a,x) (x)
49 /* ioswab[bwlq], __mem_ioswab[bwlq] are defined in mangle-port.h */
51 #define IO_SPACE_LIMIT 0xffff
54 * On MIPS I/O ports are memory mapped, so we access them using normal
55 * load/store instructions. mips_io_port_base is the virtual address to
56 * which all ports are being mapped. For sake of efficiency some code
57 * assumes that this is an address that can be loaded with a single lui
58 * instruction, so the lower 16 bits must be zero. Should be true on
59 * on any sane architecture; generic code does not use this assumption.
61 extern const unsigned long mips_io_port_base;
64 * Gcc will generate code to load the value of mips_io_port_base after each
65 * function call which may be fairly wasteful in some cases. So we don't
66 * play quite by the book. We tell gcc mips_io_port_base is a long variable
67 * which solves the code generation issue. Now we need to violate the
68 * aliasing rules a little to make initialization possible and finally we
69 * will need the barrier() to fight side effects of the aliasing chat.
70 * This trickery will eventually collapse under gcc's optimizer. Oh well.
72 static inline void set_io_port_base(unsigned long base)
74 * (unsigned long *) &mips_io_port_base = base;
75 barrier();
79 * Thanks to James van Artsdalen for a better timing-fix than
80 * the two short jumps: using outb's to a nonexistent port seems
81 * to guarantee better timings even on fast machines.
83 * On the other hand, I'd like to be sure of a non-existent port:
84 * I feel a bit unsafe about using 0x80 (should be safe, though)
86 * Linus
90 #define __SLOW_DOWN_IO \
91 __asm__ __volatile__( \
92 "sb\t$0,0x80(%0)" \
93 : : "r" (mips_io_port_base));
95 #ifdef CONF_SLOWDOWN_IO
96 #ifdef REALLY_SLOW_IO
97 #define SLOW_DOWN_IO { __SLOW_DOWN_IO; __SLOW_DOWN_IO; __SLOW_DOWN_IO; __SLOW_DOWN_IO; }
98 #else
99 #define SLOW_DOWN_IO __SLOW_DOWN_IO
100 #endif
101 #else
102 #define SLOW_DOWN_IO
103 #endif
106 * virt_to_phys - map virtual addresses to physical
107 * @address: address to remap
109 * The returned physical address is the physical (CPU) mapping for
110 * the memory address given. It is only valid to use this function on
111 * addresses directly mapped or allocated via kmalloc.
113 * This function does not give bus mappings for DMA transfers. In
114 * almost all conceivable cases a device driver should not be using
115 * this function
117 static inline unsigned long virt_to_phys(volatile const void *address)
119 return (unsigned long)address - PAGE_OFFSET + PHYS_OFFSET;
123 * phys_to_virt - map physical address to virtual
124 * @address: address to remap
126 * The returned virtual address is a current CPU mapping for
127 * the memory address given. It is only valid to use this function on
128 * addresses that have a kernel mapping
130 * This function does not handle bus mappings for DMA transfers. In
131 * almost all conceivable cases a device driver should not be using
132 * this function
134 static inline void * phys_to_virt(unsigned long address)
136 return (void *)(address + PAGE_OFFSET - PHYS_OFFSET);
140 * ISA I/O bus memory addresses are 1:1 with the physical address.
142 static inline unsigned long isa_virt_to_bus(volatile void * address)
144 return (unsigned long)address - PAGE_OFFSET;
147 static inline void * isa_bus_to_virt(unsigned long address)
149 return (void *)(address + PAGE_OFFSET);
152 #define isa_page_to_bus page_to_phys
155 * However PCI ones are not necessarily 1:1 and therefore these interfaces
156 * are forbidden in portable PCI drivers.
158 * Allow them for x86 for legacy drivers, though.
160 #define virt_to_bus virt_to_phys
161 #define bus_to_virt phys_to_virt
164 * isa_slot_offset is the address where E(ISA) busaddress 0 is mapped
165 * for the processor. This implies the assumption that there is only
166 * one of these busses.
168 extern unsigned long isa_slot_offset;
171 * Change "struct page" to physical address.
173 #define page_to_phys(page) ((dma_addr_t)page_to_pfn(page) << PAGE_SHIFT)
175 extern void __iomem * __ioremap(phys_t offset, phys_t size, unsigned long flags);
176 extern void __iounmap(const volatile void __iomem *addr);
178 static inline void __iomem * __ioremap_mode(phys_t offset, unsigned long size,
179 unsigned long flags)
181 #define __IS_LOW512(addr) (!((phys_t)(addr) & (phys_t) ~0x1fffffffULL))
183 if (cpu_has_64bit_addresses) {
184 u64 base = UNCAC_BASE;
187 * R10000 supports a 2 bit uncached attribute therefore
188 * UNCAC_BASE may not equal IO_BASE.
190 if (flags == _CACHE_UNCACHED)
191 base = (u64) IO_BASE;
192 return (void __iomem *) (unsigned long) (base + offset);
193 } else if (__builtin_constant_p(offset) &&
194 __builtin_constant_p(size) && __builtin_constant_p(flags)) {
195 phys_t phys_addr, last_addr;
197 phys_addr = fixup_bigphys_addr(offset, size);
199 /* Don't allow wraparound or zero size. */
200 last_addr = phys_addr + size - 1;
201 if (!size || last_addr < phys_addr)
202 return NULL;
205 * Map uncached objects in the low 512MB of address
206 * space using KSEG1.
208 if (__IS_LOW512(phys_addr) && __IS_LOW512(last_addr) &&
209 flags == _CACHE_UNCACHED)
210 return (void __iomem *)CKSEG1ADDR(phys_addr);
213 return __ioremap(offset, size, flags);
215 #undef __IS_LOW512
219 * ioremap - map bus memory into CPU space
220 * @offset: bus address of the memory
221 * @size: size of the resource to map
223 * ioremap performs a platform specific sequence of operations to
224 * make bus memory CPU accessible via the readb/readw/readl/writeb/
225 * writew/writel functions and the other mmio helpers. The returned
226 * address is not guaranteed to be usable directly as a virtual
227 * address.
229 #define ioremap(offset, size) \
230 __ioremap_mode((offset), (size), _CACHE_UNCACHED)
233 * ioremap_nocache - map bus memory into CPU space
234 * @offset: bus address of the memory
235 * @size: size of the resource to map
237 * ioremap_nocache performs a platform specific sequence of operations to
238 * make bus memory CPU accessible via the readb/readw/readl/writeb/
239 * writew/writel functions and the other mmio helpers. The returned
240 * address is not guaranteed to be usable directly as a virtual
241 * address.
243 * This version of ioremap ensures that the memory is marked uncachable
244 * on the CPU as well as honouring existing caching rules from things like
245 * the PCI bus. Note that there are other caches and buffers on many
246 * busses. In paticular driver authors should read up on PCI writes
248 * It's useful if some control registers are in such an area and
249 * write combining or read caching is not desirable:
251 #define ioremap_nocache(offset, size) \
252 __ioremap_mode((offset), (size), _CACHE_UNCACHED)
255 * ioremap_cachable - map bus memory into CPU space
256 * @offset: bus address of the memory
257 * @size: size of the resource to map
259 * ioremap_nocache performs a platform specific sequence of operations to
260 * make bus memory CPU accessible via the readb/readw/readl/writeb/
261 * writew/writel functions and the other mmio helpers. The returned
262 * address is not guaranteed to be usable directly as a virtual
263 * address.
265 * This version of ioremap ensures that the memory is marked cachable by
266 * the CPU. Also enables full write-combining. Useful for some
267 * memory-like regions on I/O busses.
269 #define ioremap_cachable(offset, size) \
270 __ioremap_mode((offset), (size), PAGE_CACHABLE_DEFAULT)
273 * These two are MIPS specific ioremap variant. ioremap_cacheable_cow
274 * requests a cachable mapping, ioremap_uncached_accelerated requests a
275 * mapping using the uncached accelerated mode which isn't supported on
276 * all processors.
278 #define ioremap_cacheable_cow(offset, size) \
279 __ioremap_mode((offset), (size), _CACHE_CACHABLE_COW)
280 #define ioremap_uncached_accelerated(offset, size) \
281 __ioremap_mode((offset), (size), _CACHE_UNCACHED_ACCELERATED)
283 static inline void iounmap(const volatile void __iomem *addr)
285 #define __IS_KSEG1(addr) (((unsigned long)(addr) & ~0x1fffffffUL) == CKSEG1)
287 if (cpu_has_64bit_addresses ||
288 (__builtin_constant_p(addr) && __IS_KSEG1(addr)))
289 return;
291 __iounmap(addr);
293 #undef __IS_KSEG1
296 #define __BUILD_MEMORY_SINGLE(pfx, bwlq, type, irq) \
298 static inline void pfx##write##bwlq(type val, \
299 volatile void __iomem *mem) \
301 volatile type *__mem; \
302 type __val; \
304 __mem = (void *)__swizzle_addr_##bwlq((unsigned long)(mem)); \
306 __val = pfx##ioswab##bwlq(__mem, val); \
308 if (sizeof(type) != sizeof(u64) || sizeof(u64) == sizeof(long)) \
309 *__mem = __val; \
310 else if (cpu_has_64bits) { \
311 unsigned long __flags; \
312 type __tmp; \
314 if (irq) \
315 local_irq_save(__flags); \
316 __asm__ __volatile__( \
317 ".set mips3" "\t\t# __writeq""\n\t" \
318 "dsll32 %L0, %L0, 0" "\n\t" \
319 "dsrl32 %L0, %L0, 0" "\n\t" \
320 "dsll32 %M0, %M0, 0" "\n\t" \
321 "or %L0, %L0, %M0" "\n\t" \
322 "sd %L0, %2" "\n\t" \
323 ".set mips0" "\n" \
324 : "=r" (__tmp) \
325 : "0" (__val), "m" (*__mem)); \
326 if (irq) \
327 local_irq_restore(__flags); \
328 } else \
329 BUG(); \
332 static inline type pfx##read##bwlq(const volatile void __iomem *mem) \
334 volatile type *__mem; \
335 type __val; \
337 __mem = (void *)__swizzle_addr_##bwlq((unsigned long)(mem)); \
339 if (sizeof(type) != sizeof(u64) || sizeof(u64) == sizeof(long)) \
340 __val = *__mem; \
341 else if (cpu_has_64bits) { \
342 unsigned long __flags; \
344 if (irq) \
345 local_irq_save(__flags); \
346 __asm__ __volatile__( \
347 ".set mips3" "\t\t# __readq" "\n\t" \
348 "ld %L0, %1" "\n\t" \
349 "dsra32 %M0, %L0, 0" "\n\t" \
350 "sll %L0, %L0, 0" "\n\t" \
351 ".set mips0" "\n" \
352 : "=r" (__val) \
353 : "m" (*__mem)); \
354 if (irq) \
355 local_irq_restore(__flags); \
356 } else { \
357 __val = 0; \
358 BUG(); \
361 return pfx##ioswab##bwlq(__mem, __val); \
364 #define __BUILD_IOPORT_SINGLE(pfx, bwlq, type, p, slow) \
366 static inline void pfx##out##bwlq##p(type val, unsigned long port) \
368 volatile type *__addr; \
369 type __val; \
371 __addr = (void *)__swizzle_addr_##bwlq(mips_io_port_base + port); \
373 __val = pfx##ioswab##bwlq(__addr, val); \
375 /* Really, we want this to be atomic */ \
376 BUILD_BUG_ON(sizeof(type) > sizeof(unsigned long)); \
378 *__addr = __val; \
379 slow; \
382 static inline type pfx##in##bwlq##p(unsigned long port) \
384 volatile type *__addr; \
385 type __val; \
387 __addr = (void *)__swizzle_addr_##bwlq(mips_io_port_base + port); \
389 BUILD_BUG_ON(sizeof(type) > sizeof(unsigned long)); \
391 __val = *__addr; \
392 slow; \
394 return pfx##ioswab##bwlq(__addr, __val); \
397 #define __BUILD_MEMORY_PFX(bus, bwlq, type) \
399 __BUILD_MEMORY_SINGLE(bus, bwlq, type, 1)
401 #define BUILDIO_MEM(bwlq, type) \
403 __BUILD_MEMORY_PFX(__raw_, bwlq, type) \
404 __BUILD_MEMORY_PFX(, bwlq, type) \
405 __BUILD_MEMORY_PFX(__mem_, bwlq, type) \
407 BUILDIO_MEM(b, u8)
408 BUILDIO_MEM(w, u16)
409 BUILDIO_MEM(l, u32)
410 BUILDIO_MEM(q, u64)
412 #define __BUILD_IOPORT_PFX(bus, bwlq, type) \
413 __BUILD_IOPORT_SINGLE(bus, bwlq, type, ,) \
414 __BUILD_IOPORT_SINGLE(bus, bwlq, type, _p, SLOW_DOWN_IO)
416 #define BUILDIO_IOPORT(bwlq, type) \
417 __BUILD_IOPORT_PFX(, bwlq, type) \
418 __BUILD_IOPORT_PFX(__mem_, bwlq, type)
420 BUILDIO_IOPORT(b, u8)
421 BUILDIO_IOPORT(w, u16)
422 BUILDIO_IOPORT(l, u32)
423 #ifdef CONFIG_64BIT
424 BUILDIO_IOPORT(q, u64)
425 #endif
427 #define __BUILDIO(bwlq, type) \
429 __BUILD_MEMORY_SINGLE(____raw_, bwlq, type, 0)
431 __BUILDIO(q, u64)
433 #define readb_relaxed readb
434 #define readw_relaxed readw
435 #define readl_relaxed readl
436 #define readq_relaxed readq
439 * Some code tests for these symbols
441 #define readq readq
442 #define writeq writeq
444 #define __BUILD_MEMORY_STRING(bwlq, type) \
446 static inline void writes##bwlq(volatile void __iomem *mem, \
447 const void *addr, unsigned int count) \
449 const volatile type *__addr = addr; \
451 while (count--) { \
452 __mem_write##bwlq(*__addr, mem); \
453 __addr++; \
457 static inline void reads##bwlq(volatile void __iomem *mem, void *addr, \
458 unsigned int count) \
460 volatile type *__addr = addr; \
462 while (count--) { \
463 *__addr = __mem_read##bwlq(mem); \
464 __addr++; \
468 #define __BUILD_IOPORT_STRING(bwlq, type) \
470 static inline void outs##bwlq(unsigned long port, const void *addr, \
471 unsigned int count) \
473 const volatile type *__addr = addr; \
475 while (count--) { \
476 __mem_out##bwlq(*__addr, port); \
477 __addr++; \
481 static inline void ins##bwlq(unsigned long port, void *addr, \
482 unsigned int count) \
484 volatile type *__addr = addr; \
486 while (count--) { \
487 *__addr = __mem_in##bwlq(port); \
488 __addr++; \
492 #define BUILDSTRING(bwlq, type) \
494 __BUILD_MEMORY_STRING(bwlq, type) \
495 __BUILD_IOPORT_STRING(bwlq, type)
497 BUILDSTRING(b, u8)
498 BUILDSTRING(w, u16)
499 BUILDSTRING(l, u32)
500 #ifdef CONFIG_64BIT
501 BUILDSTRING(q, u64)
502 #endif
505 /* Depends on MIPS II instruction set */
506 #define mmiowb() asm volatile ("sync" ::: "memory")
508 static inline void memset_io(volatile void __iomem *addr, unsigned char val, int count)
510 memset((void __force *) addr, val, count);
512 static inline void memcpy_fromio(void *dst, const volatile void __iomem *src, int count)
514 memcpy(dst, (void __force *) src, count);
516 static inline void memcpy_toio(volatile void __iomem *dst, const void *src, int count)
518 memcpy((void __force *) dst, src, count);
522 * ISA space is 'always mapped' on currently supported MIPS systems, no need
523 * to explicitly ioremap() it. The fact that the ISA IO space is mapped
524 * to PAGE_OFFSET is pure coincidence - it does not mean ISA values
525 * are physical addresses. The following constant pointer can be
526 * used as the IO-area pointer (it can be iounmapped as well, so the
527 * analogy with PCI is quite large):
529 #define __ISA_IO_base ((char *)(isa_slot_offset))
532 * The caches on some architectures aren't dma-coherent and have need to
533 * handle this in software. There are three types of operations that
534 * can be applied to dma buffers.
536 * - dma_cache_wback_inv(start, size) makes caches and coherent by
537 * writing the content of the caches back to memory, if necessary.
538 * The function also invalidates the affected part of the caches as
539 * necessary before DMA transfers from outside to memory.
540 * - dma_cache_wback(start, size) makes caches and coherent by
541 * writing the content of the caches back to memory, if necessary.
542 * The function also invalidates the affected part of the caches as
543 * necessary before DMA transfers from outside to memory.
544 * - dma_cache_inv(start, size) invalidates the affected parts of the
545 * caches. Dirty lines of the caches may be written back or simply
546 * be discarded. This operation is necessary before dma operations
547 * to the memory.
549 #ifdef CONFIG_DMA_NONCOHERENT
551 extern void (*_dma_cache_wback_inv)(unsigned long start, unsigned long size);
552 extern void (*_dma_cache_wback)(unsigned long start, unsigned long size);
553 extern void (*_dma_cache_inv)(unsigned long start, unsigned long size);
555 #define dma_cache_wback_inv(start, size) _dma_cache_wback_inv(start,size)
556 #define dma_cache_wback(start, size) _dma_cache_wback(start,size)
557 #define dma_cache_inv(start, size) _dma_cache_inv(start,size)
559 #else /* Sane hardware */
561 #define dma_cache_wback_inv(start,size) \
562 do { (void) (start); (void) (size); } while (0)
563 #define dma_cache_wback(start,size) \
564 do { (void) (start); (void) (size); } while (0)
565 #define dma_cache_inv(start,size) \
566 do { (void) (start); (void) (size); } while (0)
568 #endif /* CONFIG_DMA_NONCOHERENT */
571 * Read a 32-bit register that requires a 64-bit read cycle on the bus.
572 * Avoid interrupt mucking, just adjust the address for 4-byte access.
573 * Assume the addresses are 8-byte aligned.
575 #ifdef __MIPSEB__
576 #define __CSR_32_ADJUST 4
577 #else
578 #define __CSR_32_ADJUST 0
579 #endif
581 #define csr_out32(v,a) (*(volatile u32 *)((unsigned long)(a) + __CSR_32_ADJUST) = (v))
582 #define csr_in32(a) (*(volatile u32 *)((unsigned long)(a) + __CSR_32_ADJUST))
585 * Convert a physical pointer to a virtual kernel pointer for /dev/mem
586 * access
588 #define xlate_dev_mem_ptr(p) __va(p)
591 * Convert a virtual cached pointer to an uncached pointer
593 #define xlate_dev_kmem_ptr(p) p
595 #endif /* _ASM_IO_H */