/[gxemul]/trunk/src/memory_rw.c
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Revision 6 - (show annotations)
Mon Oct 8 16:18:11 2007 UTC (12 years, 2 months ago) by dpavlin
File MIME type: text/plain
File size: 16809 byte(s)
++ trunk/HISTORY	(local)
$Id: HISTORY,v 1.772 2005/06/04 12:02:16 debug Exp $
20050428	Disabling the "-fmove-all-movables" option in the configure
		script, because it causes the compile to fail on OpenBSD/sgi.
20050502	Minor updates.
20050503	Removing the WRT54G mode (it was bogus anyway), and adding a
		comment about Windows NT for MIPS in doc/experiments.html.
		Minor updates to the x86 instruction decoding.
20050504	Adding some more x86 instructions.
		Adding support for reading files from ISO9660 CDROMs (including
		gzipped files). It's an ugly hack, but it seems to work.
		Various other minor updates (dev_vga.c, pc_bios.c etc).
20050505	Some more x86-related updates.
		Beginning (what I hope will be) a major code cleanup phase.
		"bootris" (an x86 bootsector) runs :-)
20050506	Adding some more x86 instructions.
20050507	tmpnam => mkstemp.
		Working on a hack to allow VGA charcells to be shown even when
		not running with X11.
		Adding more x86 instructions.
20050508	x86 32-bit SIB addressing fix, and more instructions.
20050509	Adding more x86 instructions.
20050510	Minor documentation updates, and other updates (x86 stuff etc.)
20050511	More x86-related updates.
20050513	Various updates, mostly x86-related. (Trying to fix flag 
		calculation, factoring out the ugly shift/rotate code, and
		some other things.)
20050514	Adding support for loading some old i386 a.out executables.
		Finally beginning the cleanup of machine/PROM/bios dependant
		info.
		Some minor documentation updates.
		Trying to clean up ARCBIOS stuff a little.
20050515	Trying to make it possible to actually use more than one disk
		type per machine (floppy, ide, scsi).
		Trying to clean up the kbd vs PROM console stuff. (For PC and
		ARC emulation modes, mostly.)
		Beginning to add an 8259 interrupt controller, and connecting
		it to the x86 emulation.
20050516	The first x86 interrupts seem to work (keyboard stuff).
		Adding a 8253/8254 programmable interval timer skeleton.
		FreeDOS now reaches a command prompt and can be interacted
		with.
20050517	After some bugfixes, MS-DOS also (sometimes) reaches a
		command prompt now.
		Trying to fix the pckbc to work with MS-DOS' keyb.com, but no
		success yet.
20050518	Adding a simple 32-bit x86 MMU skeleton.
20050519	Some more work on the x86 stuff. (Beginning the work on paging,
		and various other fixes).
20050520	More updates. Working on dev_vga (4-bit graphics modes), adding
		40 columns support to the PC bios emulation.
		Trying to add support for resizing windows when switching
		between graphics modes.
20050521	Many more x86-related updates.
20050522	Correcting the initial stack pointer's sign-extension for
		ARCBIOS emulation (thanks to Alec Voropay for noticing the
		error).
		Continuing on the cleanup (ARCBIOS etc).
		dev_vga updates.
20050523	More x86 updates: trying to add some support for protected mode
		interrupts (via gate descriptors) and many other fixes.
		More ARCBIOS cleanup.
		Adding a device flag which indicates that reads cause no
		side-effects. (Useful for the "dump" command in the debugger,
		and other things.)
		Adding support for directly starting up x86 ELFs, skipping the
		bootloader stage. (Most ELFs, however, are not suitable for
		this.)
20050524	Adding simple 32-bit x86 TSS task switching, but no privilege
		level support yet.
		More work on dev_vga. A small "Copper bars" demo works. :-)
		Adding support for Trap Flag (single-step exceptions), at least
		in real mode, and various other x86-related fixes.
20050525	Adding a new disk image prefix (gH;S;) which can be used to
		override the default nr of heads and sectors per track.
20050527	Various bug fixes, more work on the x86 mode (stack change on
		interrupts between different priv.levels), and some minor
		documentation updates.
20050528	Various fixes (x86 stuff).
20050529	More x86 fixes. An OpenBSD/i386 bootfloppy reaches userland
		and can be interacted with (although there are problems with
		key repetition). NetBSD/i386 triggers a serious CISC-related
		problem: instruction fetches across page boundaries, where
		the later part isn't actually part of the instruction.
20050530	Various minor updates. (Documentation updates, etc.)
20050531	Adding some experimental code (experiments/new_test_*) which
		could be useful for dynamic (but not binary) translation in
		the future.
20050602	Adding a dummy ARM skeleton.
		Fixing the pckbc key repetition problem (by adding release
		scancodes for all keypresses).
20050603	Minor updates for the next release.
20050604	Release testing. Minor updates.

==============  RELEASE 0.3.3  ==============

20050604	There'll probably be a 0.3.3.1 release soon, with some very
		very tiny updates.


1 /*
2 * Copyright (C) 2003-2005 Anders Gavare. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions are met:
6 *
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 * 3. The name of the author may not be used to endorse or promote products
13 * derived from this software without specific prior written permission.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 *
27 *
28 * $Id: memory_rw.c,v 1.37 2005/06/02 12:31:39 debug Exp $
29 *
30 * Generic memory_rw(), with special hacks for specific CPU families.
31 *
32 * Example for inclusion from memory_mips.c:
33 *
34 * MEMORY_RW should be mips_memory_rw
35 * MEM_MIPS should be defined
36 */
37
38
39 /*
40 * memory_rw():
41 *
42 * Read or write data from/to memory.
43 *
44 * cpu the cpu doing the read/write
45 * mem the memory object to use
46 * vaddr the virtual address
47 * data a pointer to the data to be written to memory, or
48 * a placeholder for data when reading from memory
49 * len the length of the 'data' buffer
50 * writeflag set to MEM_READ or MEM_WRITE
51 * cache_flags CACHE_{NONE,DATA,INSTRUCTION} | other flags
52 *
53 * If the address indicates access to a memory mapped device, that device'
54 * read/write access function is called.
55 *
56 * If instruction latency/delay support is enabled, then
57 * cpu->instruction_delay is increased by the number of instruction to
58 * delay execution.
59 *
60 * This function should not be called with cpu == NULL.
61 *
62 * Returns one of the following:
63 * MEMORY_ACCESS_FAILED
64 * MEMORY_ACCESS_OK
65 *
66 * (MEMORY_ACCESS_FAILED is 0.)
67 */
68 int MEMORY_RW(struct cpu *cpu, struct memory *mem, uint64_t vaddr,
69 unsigned char *data, size_t len, int writeflag, int cache_flags)
70 {
71 #ifndef MEM_USERLAND
72 int ok = 1;
73 #endif
74 uint64_t paddr;
75 int cache, no_exceptions, offset;
76 unsigned char *memblock;
77 #ifdef BINTRANS
78 int bintrans_cached = cpu->machine->bintrans_enable;
79 int bintrans_device_danger = 0;
80 #endif
81 no_exceptions = cache_flags & NO_EXCEPTIONS;
82 cache = cache_flags & CACHE_FLAGS_MASK;
83
84 #ifdef MEM_PPC
85 if (cpu->cd.ppc.bits == 32)
86 vaddr &= 0xffffffff;
87 #endif
88
89 #ifdef MEM_ARM
90 vaddr &= 0x0fffffff;
91 #endif
92
93 #ifdef MEM_X86
94 /* Real-mode wrap-around: */
95 if (REAL_MODE && !(cache_flags & PHYSICAL)) {
96 if ((vaddr & 0xffff) + len > 0x10000) {
97 /* Do one byte at a time: */
98 int res = 0, i;
99 for (i=0; i<len; i++)
100 res = MEMORY_RW(cpu, mem, vaddr+i, &data[i], 1,
101 writeflag, cache_flags);
102 return res;
103 }
104 }
105
106 /* Crossing a page boundary? Then do one byte at a time: */
107 if ((vaddr & 0xfff) + len > 0x1000 && !(cache_flags & PHYSICAL)
108 && cpu->cd.x86.cr[0] & X86_CR0_PG) {
109 /* For WRITES: Read ALL BYTES FIRST and write them back!!!
110 Then do a write of all the new bytes. This is to make sure
111 than both pages around the boundary are writable so we don't
112 do a partial write. */
113 int res = 0, i;
114 if (writeflag == MEM_WRITE) {
115 unsigned char tmp;
116 for (i=0; i<len; i++) {
117 res = MEMORY_RW(cpu, mem, vaddr+i, &tmp, 1,
118 MEM_READ, cache_flags);
119 if (!res)
120 return 0;
121 res = MEMORY_RW(cpu, mem, vaddr+i, &tmp, 1,
122 MEM_WRITE, cache_flags);
123 if (!res)
124 return 0;
125 }
126 for (i=0; i<len; i++) {
127 res = MEMORY_RW(cpu, mem, vaddr+i, &data[i], 1,
128 MEM_WRITE, cache_flags);
129 if (!res)
130 return 0;
131 }
132 } else {
133 for (i=0; i<len; i++) {
134 /* Do one byte at a time: */
135 res = MEMORY_RW(cpu, mem, vaddr+i, &data[i], 1,
136 writeflag, cache_flags);
137 if (!res) {
138 if (cache == CACHE_INSTRUCTION) {
139 fatal("FAILED instruction "
140 "fetch across page boundar"
141 "y: todo. vaddr=0x%08x\n",
142 (int)vaddr);
143 cpu->running = 0;
144 }
145 return 0;
146 }
147 }
148 }
149 return res;
150 }
151 #endif /* X86 */
152
153 #ifdef MEM_URISC
154 {
155 uint64_t mask = (uint64_t) -1;
156 if (cpu->cd.urisc.wordlen < 64)
157 mask = ((int64_t)1 << cpu->cd.urisc.wordlen) - 1;
158 vaddr &= mask;
159 }
160 #endif
161
162 #ifdef MEM_MIPS
163 #ifdef BINTRANS
164 if (bintrans_cached) {
165 if (cache == CACHE_INSTRUCTION) {
166 cpu->cd.mips.pc_bintrans_host_4kpage = NULL;
167 cpu->cd.mips.pc_bintrans_paddr_valid = 0;
168 }
169 }
170 #endif
171 #endif /* MEM_MIPS */
172
173 #ifdef MEM_USERLAND
174 paddr = vaddr & 0x7fffffff;
175 goto have_paddr;
176 #endif
177
178 #ifndef MEM_USERLAND
179 #ifdef MEM_MIPS
180 /*
181 * For instruction fetch, are we on the same page as the last
182 * instruction we fetched?
183 *
184 * NOTE: There's no need to check this stuff here if this address
185 * is known to be in host ram, as it's done at instruction fetch
186 * time in cpu.c! Only check if _host_4k_page == NULL.
187 */
188 if (cache == CACHE_INSTRUCTION &&
189 cpu->cd.mips.pc_last_host_4k_page == NULL &&
190 (vaddr & ~0xfff) == cpu->cd.mips.pc_last_virtual_page) {
191 paddr = cpu->cd.mips.pc_last_physical_page | (vaddr & 0xfff);
192 goto have_paddr;
193 }
194 #endif /* MEM_MIPS */
195
196 if (cache_flags & PHYSICAL || cpu->translate_address == NULL) {
197 paddr = vaddr;
198 } else {
199 ok = cpu->translate_address(cpu, vaddr, &paddr,
200 (writeflag? FLAG_WRITEFLAG : 0) +
201 (no_exceptions? FLAG_NOEXCEPTIONS : 0)
202 #ifdef MEM_X86
203 + (cache_flags & NO_SEGMENTATION)
204 #endif
205 + (cache==CACHE_INSTRUCTION? FLAG_INSTR : 0));
206 /* If the translation caused an exception, or was invalid in
207 some way, we simply return without doing the memory
208 access: */
209 if (!ok)
210 return MEMORY_ACCESS_FAILED;
211 }
212
213
214 #ifdef MEM_X86
215 /* DOS debugging :-) */
216 if (!quiet_mode && !(cache_flags & PHYSICAL)) {
217 if (paddr >= 0x400 && paddr <= 0x4ff)
218 debug("{ PC BIOS DATA AREA: %s 0x%x }\n", writeflag ==
219 MEM_WRITE? "writing to" : "reading from",
220 (int)paddr);
221 #if 0
222 if (paddr >= 0xf0000 && paddr <= 0xfffff)
223 debug("{ BIOS ACCESS: %s 0x%x }\n",
224 writeflag == MEM_WRITE? "writing to" :
225 "reading from", (int)paddr);
226 #endif
227 }
228 #endif
229
230 #ifdef MEM_MIPS
231 /*
232 * If correct cache emulation is enabled, and we need to simluate
233 * cache misses even from the instruction cache, we can't run directly
234 * from a host page. :-/
235 */
236 #if defined(ENABLE_CACHE_EMULATION) && defined(ENABLE_INSTRUCTION_DELAYS)
237 #else
238 if (cache == CACHE_INSTRUCTION) {
239 cpu->cd.mips.pc_last_virtual_page = vaddr & ~0xfff;
240 cpu->cd.mips.pc_last_physical_page = paddr & ~0xfff;
241 cpu->cd.mips.pc_last_host_4k_page = NULL;
242
243 /* _last_host_4k_page will be set to 1 further down,
244 if the page is actually in host ram */
245 }
246 #endif
247 #endif /* MEM_MIPS */
248 #endif /* ifndef MEM_USERLAND */
249
250
251 #if defined(MEM_MIPS) || defined(MEM_USERLAND)
252 have_paddr:
253 #endif
254
255
256 #ifdef MEM_MIPS
257 /* TODO: How about bintrans vs cache emulation? */
258 #ifdef BINTRANS
259 if (bintrans_cached) {
260 if (cache == CACHE_INSTRUCTION) {
261 cpu->cd.mips.pc_bintrans_paddr_valid = 1;
262 cpu->cd.mips.pc_bintrans_paddr = paddr;
263 }
264 }
265 #endif
266 #endif /* MEM_MIPS */
267
268
269
270 #ifndef MEM_USERLAND
271 /*
272 * Memory mapped device?
273 *
274 * TODO: this is utterly slow.
275 * TODO2: if paddr<base, but len enough, then we should write
276 * to a device to
277 */
278 if (paddr >= mem->mmap_dev_minaddr && paddr < mem->mmap_dev_maxaddr) {
279 #ifdef BINTRANS
280 uint64_t orig_paddr = paddr;
281 #endif
282 int i, start, res;
283
284 #ifdef BINTRANS
285 /*
286 * Really really slow, but unfortunately necessary. This is
287 * to avoid the folowing scenario:
288 *
289 * a) offsets 0x000..0x123 are normal memory
290 * b) offsets 0x124..0x777 are a device
291 *
292 * 1) a read is done from offset 0x100. the page is
293 * added to the bintrans system as a "RAM" page
294 * 2) a bintranslated read is done from offset 0x200,
295 * which should access the device, but since the
296 * entire page is added, it will access non-existant
297 * RAM instead, without warning.
298 *
299 * Setting bintrans_device_danger = 1 on accesses which are
300 * on _any_ offset on pages that are device mapped avoids
301 * this problem, but it is probably not very fast.
302 */
303 if (bintrans_cached) {
304 for (i=0; i<mem->n_mmapped_devices; i++)
305 if (paddr >= (mem->dev_baseaddr[i] & ~0xfff) &&
306 paddr <= ((mem->dev_baseaddr[i] +
307 mem->dev_length[i] - 1) | 0xfff)) {
308 bintrans_device_danger = 1;
309 break;
310 }
311 }
312 #endif
313
314 i = start = mem->last_accessed_device;
315
316 /* Scan through all devices: */
317 do {
318 if (paddr >= mem->dev_baseaddr[i] &&
319 paddr < mem->dev_baseaddr[i] + mem->dev_length[i]) {
320 /* Found a device, let's access it: */
321 mem->last_accessed_device = i;
322
323 paddr -= mem->dev_baseaddr[i];
324 if (paddr + len > mem->dev_length[i])
325 len = mem->dev_length[i] - paddr;
326
327 #ifdef BINTRANS
328 if (bintrans_cached && mem->dev_flags[i] &
329 MEM_BINTRANS_OK) {
330 int wf = writeflag == MEM_WRITE? 1 : 0;
331
332 if (writeflag) {
333 if (paddr < mem->
334 dev_bintrans_write_low[i])
335 mem->
336 dev_bintrans_write_low
337 [i] =
338 paddr & ~0xfff;
339 if (paddr > mem->
340 dev_bintrans_write_high[i])
341 mem->
342 dev_bintrans_write_high
343 [i] = paddr | 0xfff;
344 }
345
346 if (!(mem->dev_flags[i] &
347 MEM_BINTRANS_WRITE_OK))
348 wf = 0;
349
350 update_translation_table(cpu,
351 vaddr & ~0xfff,
352 mem->dev_bintrans_data[i] +
353 (paddr & ~0xfff),
354 wf, orig_paddr & ~0xfff);
355 }
356 #endif
357
358 res = 0;
359 if (!no_exceptions || (mem->dev_flags[i] &
360 MEM_READING_HAS_NO_SIDE_EFFECTS))
361 res = mem->dev_f[i](cpu, mem, paddr,
362 data, len, writeflag,
363 mem->dev_extra[i]);
364
365 #ifdef ENABLE_INSTRUCTION_DELAYS
366 if (res == 0)
367 res = -1;
368
369 cpu->cd.mips.instruction_delay +=
370 ( (abs(res) - 1) *
371 cpu->cd.mips.cpu_type.instrs_per_cycle );
372 #endif
373
374 #ifndef MEM_X86
375 /*
376 * If accessing the memory mapped device
377 * failed, then return with a DBE exception.
378 */
379 if (res <= 0 && !no_exceptions) {
380 debug("%s device '%s' addr %08lx "
381 "failed\n", writeflag?
382 "writing to" : "reading from",
383 mem->dev_name[i], (long)paddr);
384 #ifdef MEM_MIPS
385 mips_cpu_exception(cpu, EXCEPTION_DBE,
386 0, vaddr, 0, 0, 0, 0);
387 #endif
388 return MEMORY_ACCESS_FAILED;
389 }
390 #endif
391 goto do_return_ok;
392 }
393
394 i ++;
395 if (i == mem->n_mmapped_devices)
396 i = 0;
397 } while (i != start);
398 }
399
400
401 #ifdef MEM_MIPS
402 /*
403 * Data and instruction cache emulation:
404 */
405
406 switch (cpu->cd.mips.cpu_type.mmu_model) {
407 case MMU3K:
408 /* if not uncached addess (TODO: generalize this) */
409 if (!(cache_flags & PHYSICAL) && cache != CACHE_NONE &&
410 !((vaddr & 0xffffffffULL) >= 0xa0000000ULL &&
411 (vaddr & 0xffffffffULL) <= 0xbfffffffULL)) {
412 if (memory_cache_R3000(cpu, cache, paddr,
413 writeflag, len, data))
414 goto do_return_ok;
415 }
416 break;
417 #if 0
418 /* Remove this, it doesn't work anyway */
419 case MMU10K:
420 /* other cpus: */
421 /*
422 * SUPER-UGLY HACK for SGI-IP32 PROM, R10000:
423 * K0 bits == 0x3 means uncached...
424 *
425 * It seems that during bootup, the SGI-IP32 prom
426 * stores a return pointers a 0x80000f10, then tests
427 * memory by writing bit patterns to 0xa0000xxx, and
428 * then when it's done, reads back the return pointer
429 * from 0x80000f10.
430 *
431 * I need to find the correct way to disconnect the
432 * cache from the main memory for R10000. (TODO !!!)
433 */
434 /* if ((cpu->cd.mips.coproc[0]->reg[COP0_CONFIG] & 7) == 3) { */
435 /*
436 if (cache == CACHE_DATA &&
437 cpu->r10k_cache_disable_TODO) {
438 paddr &= ((512*1024)-1);
439 paddr += 512*1024;
440 }
441 */
442 break;
443 #endif
444 default:
445 /* R4000 etc */
446 /* TODO */
447 ;
448 }
449 #endif /* MEM_MIPS */
450
451
452 /* Outside of physical RAM? */
453 if (paddr >= mem->physical_max) {
454 #ifdef MEM_MIPS
455 if ((paddr & 0xffffc00000ULL) == 0x1fc00000) {
456 /* Ok, this is PROM stuff */
457 } else if ((paddr & 0xfffff00000ULL) == 0x1ff00000) {
458 /* Sprite reads from this area of memory... */
459 /* TODO: is this still correct? */
460 if (writeflag == MEM_READ)
461 memset(data, 0, len);
462 goto do_return_ok;
463 } else
464 #endif /* MIPS */
465 {
466 if (paddr >= mem->physical_max) {
467 char *symbol;
468 #ifdef MEM_MIPS
469 uint64_t offset;
470 #endif
471 /* This allows for example OS kernels to probe
472 memory a few KBs past the end of memory,
473 without giving too many warnings. */
474 if (!quiet_mode && paddr >=
475 mem->physical_max + 0x40000) {
476 fatal("[ memory_rw(): writeflag=%i ",
477 writeflag);
478 if (writeflag) {
479 unsigned int i;
480 debug("data={", writeflag);
481 if (len > 16) {
482 int start2 = len-16;
483 for (i=0; i<16; i++)
484 debug("%s%02x",
485 i?",":"",
486 data[i]);
487 debug(" .. ");
488 if (start2 < 16)
489 start2 = 16;
490 for (i=start2; i<len;
491 i++)
492 debug("%s%02x",
493 i?",":"",
494 data[i]);
495 } else
496 for (i=0; i<len; i++)
497 debug("%s%02x",
498 i?",":"",
499 data[i]);
500 debug("}");
501 }
502 #ifdef MEM_MIPS
503 symbol = get_symbol_name(
504 &cpu->machine->symbol_context,
505 cpu->cd.mips.pc_last, &offset);
506 #else
507 symbol = "(unimpl for non-MIPS)";
508 #endif
509
510 /* TODO: fix! not mips.pc_last for for example ppc */
511
512 fatal(" paddr=%llx >= physical_max pc="
513 "0x%08llx <%s> ]\n",
514 (long long)paddr,
515 (long long)cpu->cd.mips.pc_last,
516 symbol? symbol : "no symbol");
517 }
518
519 if (cpu->machine->single_step_on_bad_addr) {
520 fatal("[ unimplemented access to "
521 "0x%016llx, pc = 0x%016llx ]\n",
522 (long long)paddr,
523 (long long)cpu->pc);
524 single_step = 1;
525 }
526 }
527
528 if (writeflag == MEM_READ) {
529 #ifdef MEM_X86
530 /* Reading non-existant memory on x86: */
531 memset(data, 0xff, len);
532 #else
533 /* Return all zeroes? (Or 0xff? TODO) */
534 memset(data, 0, len);
535 #endif
536
537 #ifdef MEM_MIPS
538 /*
539 * For real data/instruction accesses, cause
540 * an exceptions on an illegal read:
541 */
542 if (cache != CACHE_NONE && cpu->machine->
543 dbe_on_nonexistant_memaccess &&
544 !no_exceptions) {
545 if (paddr >= mem->physical_max &&
546 paddr < mem->physical_max+1048576)
547 mips_cpu_exception(cpu,
548 EXCEPTION_DBE, 0, vaddr, 0,
549 0, 0, 0);
550 }
551 #endif /* MEM_MIPS */
552 }
553
554 /* Hm? Shouldn't there be a DBE exception for
555 invalid writes as well? TODO */
556
557 goto do_return_ok;
558 }
559 }
560
561 #endif /* ifndef MEM_USERLAND */
562
563
564 /*
565 * Uncached access:
566 */
567 memblock = memory_paddr_to_hostaddr(mem, paddr, writeflag);
568 if (memblock == NULL) {
569 if (writeflag == MEM_READ)
570 memset(data, 0, len);
571 goto do_return_ok;
572 }
573
574 offset = paddr & ((1 << BITS_PER_MEMBLOCK) - 1);
575
576 #ifdef BINTRANS
577 if (bintrans_cached && !bintrans_device_danger)
578 update_translation_table(cpu, vaddr & ~0xfff,
579 memblock + (offset & ~0xfff),
580 #if 0
581 cache == CACHE_INSTRUCTION?
582 (writeflag == MEM_WRITE? 1 : 0)
583 : ok - 1,
584 #else
585 writeflag == MEM_WRITE? 1 : 0,
586 #endif
587 paddr & ~0xfff);
588 #endif
589
590 if (writeflag == MEM_WRITE) {
591 if (len == sizeof(uint32_t) && (offset & 3)==0)
592 *(uint32_t *)(memblock + offset) = *(uint32_t *)data;
593 else if (len == sizeof(uint8_t))
594 *(uint8_t *)(memblock + offset) = *(uint8_t *)data;
595 else
596 memcpy(memblock + offset, data, len);
597 } else {
598 if (len == sizeof(uint32_t) && (offset & 3)==0)
599 *(uint32_t *)data = *(uint32_t *)(memblock + offset);
600 else if (len == sizeof(uint8_t))
601 *(uint8_t *)data = *(uint8_t *)(memblock + offset);
602 else
603 memcpy(data, memblock + offset, len);
604
605 #ifdef MEM_MIPS
606 if (cache == CACHE_INSTRUCTION) {
607 cpu->cd.mips.pc_last_host_4k_page = memblock
608 + (offset & ~0xfff);
609 #ifdef BINTRANS
610 if (bintrans_cached) {
611 cpu->cd.mips.pc_bintrans_host_4kpage =
612 cpu->cd.mips.pc_last_host_4k_page;
613 }
614 #endif
615 }
616 #endif /* MIPS */
617 }
618
619
620 do_return_ok:
621 return MEMORY_ACCESS_OK;
622 }
623

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