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 */
set_io_port_base(unsigned long base)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 */
virt_to_phys(volatile const void * address)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 */
phys_to_virt(unsigned long address)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 */
isa_virt_to_bus(volatile void * address)144 static inline unsigned long isa_virt_to_bus(volatile void * address)
145 {
146 return (unsigned long)address - PAGE_OFFSET;
147 }
148
isa_bus_to_virt(unsigned long address)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;
pci_iounmap(struct pci_dev * dev,void __iomem * addr)175 static inline void pci_iounmap(struct pci_dev *dev, void __iomem *addr) {}
176 #endif
177
__ioremap_mode(phys_addr_t offset,unsigned long size,unsigned long flags)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
iounmap(const volatile void __iomem * addr)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
BUILDIO_MEM(b,u8)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 }
memcpy_fromio(void * dst,const volatile void __iomem * src,int count)558 static inline void memcpy_fromio(void *dst, const volatile void __iomem *src, int count)
559 {
560 memcpy(dst, (void __force *) src, count);
561 }
memcpy_toio(volatile void __iomem * dst,const void * src,int count)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