File: /usr/src/linux/include/asm-mips/io.h

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 Ralf Baechle
8      * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
9      * Copyright (C) 2000 FSMLabs, Inc.
10      */
11     #ifndef _ASM_IO_H
12     #define _ASM_IO_H
13     
14     #include <linux/config.h>
15     #include <linux/pagemap.h>
16     #include <asm/addrspace.h>
17     #include <asm/byteorder.h>
18     
19     /*
20      * Slowdown I/O port space accesses for antique hardware.
21      */
22     #undef CONF_SLOWDOWN_IO
23     
24     /*
25      * Sane hardware offers swapping of I/O space accesses in hardware; less
26      * sane hardware forces software to fiddle with this ...
27      */
28     #if defined(CONFIG_SWAP_IO_SPACE) && defined(__MIPSEB__)
29     
30     #define __ioswab8(x) (x)
31     #define __ioswab16(x) swab16(x)
32     #define __ioswab32(x) swab32(x)
33     
34     #else
35     
36     #define __ioswab8(x) (x)
37     #define __ioswab16(x) (x)
38     #define __ioswab32(x) (x)
39     
40     #endif
41     
42     /*
43      * This file contains the definitions for the MIPS counterpart of the
44      * x86 in/out instructions. This heap of macros and C results in much
45      * better code than the approach of doing it in plain C.  The macros
46      * result in code that is to fast for certain hardware.  On the other
47      * side the performance of the string functions should be improved for
48      * sake of certain devices like EIDE disks that do highspeed polled I/O.
49      *
50      *   Ralf
51      *
52      * This file contains the definitions for the x86 IO instructions
53      * inb/inw/inl/outb/outw/outl and the "string versions" of the same
54      * (insb/insw/insl/outsb/outsw/outsl). You can also use "pausing"
55      * versions of the single-IO instructions (inb_p/inw_p/..).
56      *
57      * This file is not meant to be obfuscating: it's just complicated
58      * to (a) handle it all in a way that makes gcc able to optimize it
59      * as well as possible and (b) trying to avoid writing the same thing
60      * over and over again with slight variations and possibly making a
61      * mistake somewhere.
62      */
63     
64     /*
65      * On MIPS I/O ports are memory mapped, so we access them using normal
66      * load/store instructions. mips_io_port_base is the virtual address to
67      * which all ports are being mapped.  For sake of efficiency some code
68      * assumes that this is an address that can be loaded with a single lui
69      * instruction, so the lower 16 bits must be zero.  Should be true on
70      * on any sane architecture; generic code does not use this assumption.
71      */
72     extern unsigned long mips_io_port_base;
73     
74     /*
75      * Thanks to James van Artsdalen for a better timing-fix than
76      * the two short jumps: using outb's to a nonexistent port seems
77      * to guarantee better timings even on fast machines.
78      *
79      * On the other hand, I'd like to be sure of a non-existent port:
80      * I feel a bit unsafe about using 0x80 (should be safe, though)
81      *
82      *		Linus
83      *
84      */
85     
86     #define __SLOW_DOWN_IO \
87     	__asm__ __volatile__( \
88     		"sb\t$0,0x80(%0)" \
89     		: : "r" (mips_io_port_base));
90     
91     #ifdef CONF_SLOWDOWN_IO
92     #ifdef REALLY_SLOW_IO
93     #define SLOW_DOWN_IO { __SLOW_DOWN_IO; __SLOW_DOWN_IO; __SLOW_DOWN_IO; __SLOW_DOWN_IO; }
94     #else
95     #define SLOW_DOWN_IO __SLOW_DOWN_IO
96     #endif
97     #else
98     #define SLOW_DOWN_IO
99     #endif
100     
101     /*
102      * Change virtual addresses to physical addresses and vv.
103      * These are trivial on the 1:1 Linux/MIPS mapping
104      */
105     extern inline unsigned long virt_to_phys(volatile void * address)
106     {
107     	return PHYSADDR(address);
108     }
109     
110     extern inline void * phys_to_virt(unsigned long address)
111     {
112     	return (void *)KSEG0ADDR(address);
113     }
114     
115     /*
116      * IO bus memory addresses are also 1:1 with the physical address
117      */
118     extern inline unsigned long virt_to_bus(volatile void * address)
119     {
120     	return PHYSADDR(address);
121     }
122     
123     extern inline void * bus_to_virt(unsigned long address)
124     {
125     	return (void *)KSEG0ADDR(address);
126     }
127     
128     /*
129      * isa_slot_offset is the address where E(ISA) busaddress 0 is mapped
130      * for the processor.
131      */
132     extern unsigned long isa_slot_offset;
133     
134     extern void * __ioremap(unsigned long offset, unsigned long size, unsigned long flags);
135     
136     extern inline void *ioremap(unsigned long offset, unsigned long size)
137     {
138     	return __ioremap(offset, size, _CACHE_UNCACHED);
139     }
140     
141     extern inline void *ioremap_nocache(unsigned long offset, unsigned long size)
142     {
143     	return __ioremap(offset, size, _CACHE_UNCACHED);
144     }
145     
146     extern void iounmap(void *addr);
147     
148     /*
149      * XXX We need system specific versions of these to handle EISA address bits
150      * 24-31 on SNI.
151      * XXX more SNI hacks.
152      */
153     #define readb(addr) (*(volatile unsigned char *)(addr))
154     #define readw(addr) __ioswab16((*(volatile unsigned short *)(addr)))
155     #define readl(addr) __ioswab32((*(volatile unsigned int *)(addr)))
156     #define __raw_readb readb
157     #define __raw_readw readw
158     #define __raw_readl readl
159     
160     #define writeb(b,addr) (*(volatile unsigned char *)(addr)) = (b)
161     #define writew(b,addr) (*(volatile unsigned short *)(addr)) = (__ioswab16(b))
162     #define writel(b,addr) (*(volatile unsigned int *)(addr)) = (__ioswab32(b))
163     #define __raw_writeb writeb
164     #define __raw_writew writew
165     #define __raw_writel writel
166     
167     #define memset_io(a,b,c)	memset((void *)(a),(b),(c))
168     #define memcpy_fromio(a,b,c)	memcpy((a),(void *)(b),(c))
169     #define memcpy_toio(a,b,c)	memcpy((void *)(a),(b),(c))
170     
171     /* END SNI HACKS ... */
172     
173     /*
174      * ISA space is 'always mapped' on currently supported MIPS systems, no need
175      * to explicitly ioremap() it. The fact that the ISA IO space is mapped
176      * to PAGE_OFFSET is pure coincidence - it does not mean ISA values
177      * are physical addresses. The following constant pointer can be
178      * used as the IO-area pointer (it can be iounmapped as well, so the
179      * analogy with PCI is quite large):
180      */
181     #define __ISA_IO_base ((char *)(PAGE_OFFSET))
182     
183     #define isa_readb(a) readb(a)
184     #define isa_readw(a) readw(a)
185     #define isa_readl(a) readl(a)
186     #define isa_writeb(b,a) writeb(b,a)
187     #define isa_writew(w,a) writew(w,a)
188     #define isa_writel(l,a) writel(l,a)
189     
190     #define isa_memset_io(a,b,c)     memset_io((a),(b),(c))
191     #define isa_memcpy_fromio(a,b,c) memcpy_fromio((a),(b),(c))
192     #define isa_memcpy_toio(a,b,c)   memcpy_toio((a),(b),(c))
193     
194     /*
195      * We don't have csum_partial_copy_fromio() yet, so we cheat here and
196      * just copy it. The net code will then do the checksum later.
197      */
198     #define eth_io_copy_and_sum(skb,src,len,unused) memcpy_fromio((skb)->data,(src),(len))
199     #define isa_eth_io_copy_and_sum(a,b,c,d) eth_copy_and_sum((a),(b),(c),(d))
200     
201     static inline int check_signature(unsigned long io_addr,
202                                       const unsigned char *signature, int length)
203     {
204     	int retval = 0;
205     	do {
206     		if (readb(io_addr) != *signature)
207     			goto out;
208     		io_addr++;
209     		signature++;
210     		length--;
211     	} while (length);
212     	retval = 1;
213     out:
214     	return retval;
215     }
216     #define isa_check_signature(io, s, l) check_signature(i,s,l)
217     
218     /*
219      * Talk about misusing macros..
220      */
221     
222     #define __OUT1(s) \
223     extern inline void __out##s(unsigned int value, unsigned int port) {
224     
225     #define __OUT2(m) \
226     __asm__ __volatile__ ("s" #m "\t%0,%1(%2)"
227     
228     #define __OUT(m,s,w) \
229     __OUT1(s) __OUT2(m) : : "r" (__ioswab##w(value)), "i" (0), "r" (mips_io_port_base+port)); } \
230     __OUT1(s##c) __OUT2(m) : : "r" (__ioswab##w(value)), "ir" (port), "r" (mips_io_port_base)); } \
231     __OUT1(s##_p) __OUT2(m) : : "r" (__ioswab##w(value)), "i" (0), "r" (mips_io_port_base+port)); \
232     	SLOW_DOWN_IO; } \
233     __OUT1(s##c_p) __OUT2(m) : : "r" (__ioswab##w(value)), "ir" (port), "r" (mips_io_port_base)); \
234     	SLOW_DOWN_IO; }
235     
236     #define __IN1(t,s) \
237     extern __inline__ t __in##s(unsigned int port) { t _v;
238     
239     /*
240      * Required nops will be inserted by the assembler
241      */
242     #define __IN2(m) \
243     __asm__ __volatile__ ("l" #m "\t%0,%1(%2)"
244     
245     #define __IN(t,m,s,w) \
246     __IN1(t,s) __IN2(m) : "=r" (_v) : "i" (0), "r" (mips_io_port_base+port)); return __ioswab##w(_v); } \
247     __IN1(t,s##c) __IN2(m) : "=r" (_v) : "ir" (port), "r" (mips_io_port_base)); return __ioswab##w(_v); } \
248     __IN1(t,s##_p) __IN2(m) : "=r" (_v) : "i" (0), "r" (mips_io_port_base+port)); SLOW_DOWN_IO; return __ioswab##w(_v); } \
249     __IN1(t,s##c_p) __IN2(m) : "=r" (_v) : "ir" (port), "r" (mips_io_port_base)); SLOW_DOWN_IO; return __ioswab##w(_v); }
250     
251     #define __INS1(s) \
252     extern inline void __ins##s(unsigned int port, void * addr, unsigned long count) {
253     
254     #define __INS2(m) \
255     if (count) \
256     __asm__ __volatile__ ( \
257     	".set\tnoreorder\n\t" \
258     	".set\tnoat\n" \
259     	"1:\tl" #m "\t$1,%4(%5)\n\t" \
260     	"subu\t%1,1\n\t" \
261     	"s" #m "\t$1,(%0)\n\t" \
262     	"bne\t$0,%1,1b\n\t" \
263     	"addiu\t%0,%6\n\t" \
264     	".set\tat\n\t" \
265     	".set\treorder"
266     
267     #define __INS(m,s,i) \
268     __INS1(s) __INS2(m) \
269     	: "=r" (addr), "=r" (count) \
270     	: "0" (addr), "1" (count), "i" (0), \
271     	  "r" (mips_io_port_base+port), "I" (i) \
272     	: "$1");} \
273     __INS1(s##c) __INS2(m) \
274     	: "=r" (addr), "=r" (count) \
275     	: "0" (addr), "1" (count), "ir" (port), \
276     	  "r" (mips_io_port_base), "I" (i) \
277     	: "$1");}
278     
279     #define __OUTS1(s) \
280     extern inline void __outs##s(unsigned int port, const void * addr, unsigned long count) {
281     
282     #define __OUTS2(m) \
283     if (count) \
284     __asm__ __volatile__ ( \
285             ".set\tnoreorder\n\t" \
286             ".set\tnoat\n" \
287             "1:\tl" #m "\t$1,(%0)\n\t" \
288             "subu\t%1,1\n\t" \
289             "s" #m "\t$1,%4(%5)\n\t" \
290             "bne\t$0,%1,1b\n\t" \
291             "addiu\t%0,%6\n\t" \
292             ".set\tat\n\t" \
293             ".set\treorder"
294     
295     #define __OUTS(m,s,i) \
296     __OUTS1(s) __OUTS2(m) \
297     	: "=r" (addr), "=r" (count) \
298     	: "0" (addr), "1" (count), "i" (0), "r" (mips_io_port_base+port), "I" (i) \
299     	: "$1");} \
300     __OUTS1(s##c) __OUTS2(m) \
301     	: "=r" (addr), "=r" (count) \
302     	: "0" (addr), "1" (count), "ir" (port), "r" (mips_io_port_base), "I" (i) \
303     	: "$1");}
304     
305     __IN(unsigned char,b,b,8)
306     __IN(unsigned short,h,w,16)
307     __IN(unsigned int,w,l,32)
308     
309     __OUT(b,b,8)
310     __OUT(h,w,16)
311     __OUT(w,l,32)
312     
313     __INS(b,b,1)
314     __INS(h,w,2)
315     __INS(w,l,4)
316     
317     __OUTS(b,b,1)
318     __OUTS(h,w,2)
319     __OUTS(w,l,4)
320     
321     
322     /*
323      * Note that due to the way __builtin_constant_p() works, you
324      *  - can't use it inside an inline function (it will never be true)
325      *  - you don't have to worry about side effects within the __builtin..
326      */
327     #define outb(val,port) \
328     ((__builtin_constant_p((port)) && (port) < 32768) ? \
329     	__outbc((val),(port)) : \
330     	__outb((val),(port)))
331     
332     #define inb(port) \
333     ((__builtin_constant_p((port)) && (port) < 32768) ? \
334     	__inbc(port) : \
335     	__inb(port))
336     
337     #define outb_p(val,port) \
338     ((__builtin_constant_p((port)) && (port) < 32768) ? \
339     	__outbc_p((val),(port)) : \
340     	__outb_p((val),(port)))
341     
342     #define inb_p(port) \
343     ((__builtin_constant_p((port)) && (port) < 32768) ? \
344     	__inbc_p(port) : \
345     	__inb_p(port))
346     
347     #define outw(val,port) \
348     ((__builtin_constant_p((port)) && (port) < 32768) ? \
349     	__outwc((val),(port)) : \
350     	__outw((val),(port)))
351     
352     #define inw(port) \
353     ((__builtin_constant_p((port)) && (port) < 32768) ? \
354     	__inwc(port) : \
355     	__inw(port))
356     
357     #define outw_p(val,port) \
358     ((__builtin_constant_p((port)) && (port) < 32768) ? \
359     	__outwc_p((val),(port)) : \
360     	__outw_p((val),(port)))
361     
362     #define inw_p(port) \
363     ((__builtin_constant_p((port)) && (port) < 32768) ? \
364     	__inwc_p(port) : \
365     	__inw_p(port))
366     
367     #define outl(val,port) \
368     ((__builtin_constant_p((port)) && (port) < 32768) ? \
369     	__outlc((val),(port)) : \
370     	__outl((val),(port)))
371     
372     #define inl(port) \
373     ((__builtin_constant_p((port)) && (port) < 32768) ? \
374     	__inlc(port) : \
375     	__inl(port))
376     
377     #define outl_p(val,port) \
378     ((__builtin_constant_p((port)) && (port) < 32768) ? \
379     	__outlc_p((val),(port)) : \
380     	__outl_p((val),(port)))
381     
382     #define inl_p(port) \
383     ((__builtin_constant_p((port)) && (port) < 32768) ? \
384     	__inlc_p(port) : \
385     	__inl_p(port))
386     
387     
388     #define outsb(port,addr,count) \
389     ((__builtin_constant_p((port)) && (port) < 32768) ? \
390     	__outsbc((port),(addr),(count)) : \
391     	__outsb ((port),(addr),(count)))
392     
393     #define insb(port,addr,count) \
394     ((__builtin_constant_p((port)) && (port) < 32768) ? \
395     	__insbc((port),(addr),(count)) : \
396     	__insb((port),(addr),(count)))
397     
398     #define outsw(port,addr,count) \
399     ((__builtin_constant_p((port)) && (port) < 32768) ? \
400     	__outswc((port),(addr),(count)) : \
401     	__outsw ((port),(addr),(count)))
402     
403     #define insw(port,addr,count) \
404     ((__builtin_constant_p((port)) && (port) < 32768) ? \
405     	__inswc((port),(addr),(count)) : \
406     	__insw((port),(addr),(count)))
407     
408     #define outsl(port,addr,count) \
409     ((__builtin_constant_p((port)) && (port) < 32768) ? \
410     	__outslc((port),(addr),(count)) : \
411     	__outsl ((port),(addr),(count)))
412     
413     #define insl(port,addr,count) \
414     ((__builtin_constant_p((port)) && (port) < 32768) ? \
415     	__inslc((port),(addr),(count)) : \
416     	__insl((port),(addr),(count)))
417     
418     #define IO_SPACE_LIMIT 0xffff
419     
420     /*
421      * The caches on some architectures aren't dma-coherent and have need to
422      * handle this in software.  There are three types of operations that
423      * can be applied to dma buffers.
424      *
425      *  - dma_cache_wback_inv(start, size) makes caches and coherent by
426      *    writing the content of the caches back to memory, if necessary.
427      *    The function also invalidates the affected part of the caches as
428      *    necessary before DMA transfers from outside to memory.
429      *  - dma_cache_wback(start, size) makes caches and coherent by
430      *    writing the content of the caches back to memory, if necessary.
431      *    The function also invalidates the affected part of the caches as
432      *    necessary before DMA transfers from outside to memory.
433      *  - dma_cache_inv(start, size) invalidates the affected parts of the
434      *    caches.  Dirty lines of the caches may be written back or simply
435      *    be discarded.  This operation is necessary before dma operations
436      *    to the memory.
437      */
438     extern void (*_dma_cache_wback_inv)(unsigned long start, unsigned long size);
439     extern void (*_dma_cache_wback)(unsigned long start, unsigned long size);
440     extern void (*_dma_cache_inv)(unsigned long start, unsigned long size);
441     
442     #define dma_cache_wback_inv(start,size)	_dma_cache_wback_inv(start,size)
443     #define dma_cache_wback(start,size)	_dma_cache_wback(start,size)
444     #define dma_cache_inv(start,size)	_dma_cache_inv(start,size)
445     
446     #endif /* _ASM_IO_H */
447