xref: /haiku/src/system/boot/platform/openfirmware/arch/sparc/mmu.cpp (revision 4b918abdb02a26a770d898594eaaccc6f1726e9b)
1 /*
2  * Copyright 2003-2009, Axel Dörfler, axeld@pinc-software.de.
3  * Copyright 2010-2011, Haiku, Inc. All Rights Reserved.
4  * All rights reserved. Distributed under the terms of the MIT License.
5  *
6  * Authors:
7  *		Axel Dörfler, axeld@pinc-software.de.
8  *		Alexander von Gluck, kallisti5@unixzen.com
9  */
10 
11 
12 #include <OS.h>
13 
14 #include <platform_arch.h>
15 #include <boot/addr_range.h>
16 #include <boot/kernel_args.h>
17 #include <boot/platform.h>
18 #include <boot/stage2.h>
19 #include <boot/stdio.h>
20 #include <platform/openfirmware/openfirmware.h>
21 #include <arch_cpu.h>
22 #include <arch_mmu.h>
23 #include <kernel.h>
24 
25 #include "support.h"
26 
27 
28 #define PAGE_READ_ONLY	0x0002
29 #define PAGE_READ_WRITE	0x0001
30 
31 // NULL is actually a possible physical address, so use -1 (which is
32 // misaligned, so not a valid address) as the invalid physical address.
33 #define PHYSINVAL ((void *)-1)
34 //#define PHYSINVAL NULL
35 
36 //#define TRACE_MMU
37 #ifdef TRACE_MMU
38 #   define TRACE(x...) dprintf(x)
39 #else
40 #   define TRACE(x...) ;
41 #endif
42 
43 
44 unsigned int sMmuInstance;
45 unsigned int sMemoryInstance;
46 
47 
48 // begin and end of the boot loader
49 extern "C" uint8 __text_begin;
50 extern "C" uint8 _end;
51 
52 
53 static status_t
54 insert_virtual_range_to_keep(void *start, uint32 size)
55 {
56 	return insert_address_range(gKernelArgs.arch_args.virtual_ranges_to_keep,
57 		&gKernelArgs.arch_args.num_virtual_ranges_to_keep,
58 		MAX_VIRTUAL_RANGES_TO_KEEP, (addr_t)start, size);
59 }
60 
61 
62 static status_t
63 remove_virtual_range_to_keep(void *start, uint32 size)
64 {
65 	return remove_address_range(gKernelArgs.arch_args.virtual_ranges_to_keep,
66 		&gKernelArgs.arch_args.num_virtual_ranges_to_keep,
67 		MAX_VIRTUAL_RANGES_TO_KEEP, (addr_t)start, size);
68 }
69 
70 
71 static status_t
72 find_physical_memory_ranges(size_t &total)
73 {
74 	TRACE("checking for memory...\n");
75 	intptr_t package = of_instance_to_package(sMemoryInstance);
76 
77 	total = 0;
78 
79 	// Memory base addresses are provided in 32 or 64 bit flavors
80 	// #address-cells and #size-cells matches the number of 32-bit 'cells'
81 	// representing the length of the base address and size fields
82 	intptr_t root = of_finddevice("/");
83 	int32 regSizeCells = of_size_cells(root);
84 	if (regSizeCells == OF_FAILED) {
85 		dprintf("finding size of memory cells failed, assume 32-bit.\n");
86 		regSizeCells = 1;
87 	}
88 
89 	int32 regAddressCells = of_address_cells(root);
90 	if (regAddressCells == OF_FAILED) {
91 		// Sun Netra T1-105 is missing this, but we can guess that if the size
92 		// is 64bit, the address also likely is.
93 		regAddressCells = regSizeCells;
94 	}
95 
96 	if (regAddressCells != 2 || regSizeCells != 2) {
97 		panic("%s: Unsupported OpenFirmware cell count detected.\n"
98 		"Address Cells: %" B_PRId32 "; Size Cells: %" B_PRId32
99 		" (CPU > 64bit?).\n", __func__, regAddressCells, regSizeCells);
100 		return B_ERROR;
101 	}
102 
103 	struct of_region<uint64, uint64> regions[64];
104 	int count = of_getprop(package, "reg", regions, sizeof(regions));
105 	if (count == OF_FAILED)
106 		count = of_getprop(sMemoryInstance, "reg", regions, sizeof(regions));
107 	if (count == OF_FAILED)
108 		return B_ERROR;
109 	count /= sizeof(regions[0]);
110 
111 	for (int32 i = 0; i < count; i++) {
112 		if (regions[i].size <= 0) {
113 			TRACE("%d: empty region\n", i);
114 			continue;
115 		}
116 		TRACE("%" B_PRIu32 ": base = %" B_PRIx64 ","
117 			"size = %" B_PRIx64 "\n", i, regions[i].base, regions[i].size);
118 
119 		total += regions[i].size;
120 
121 		if (insert_physical_memory_range((addr_t)regions[i].base,
122 				regions[i].size) != B_OK) {
123 			dprintf("cannot map physical memory range "
124 				"(num ranges = %" B_PRIu32 ")!\n",
125 				gKernelArgs.num_physical_memory_ranges);
126 			return B_ERROR;
127 		}
128 	}
129 
130 	return B_OK;
131 }
132 
133 
134 static bool
135 is_virtual_allocated(void *address, size_t size)
136 {
137 	uint64 foundBase;
138 	return !get_free_address_range(gKernelArgs.virtual_allocated_range,
139 		gKernelArgs.num_virtual_allocated_ranges, (addr_t)address, size,
140 		&foundBase) || foundBase != (addr_t)address;
141 }
142 
143 
144 static bool
145 is_physical_allocated(void *address, size_t size)
146 {
147 	uint64 foundBase;
148 	return !get_free_address_range(gKernelArgs.physical_allocated_range,
149 		gKernelArgs.num_physical_allocated_ranges, (addr_t)address, size,
150 		&foundBase) || foundBase != (addr_t)address;
151 }
152 
153 
154 static bool
155 is_physical_memory(void *address, size_t size = 1)
156 {
157 	return is_address_range_covered(gKernelArgs.physical_memory_range,
158 		gKernelArgs.num_physical_memory_ranges, (addr_t)address, size);
159 }
160 
161 
162 static bool
163 map_range(void *virtualAddress, void *physicalAddress, size_t size, uint16 mode)
164 {
165 	// everything went fine, so lets mark the space as used.
166 	int status = of_call_method(sMmuInstance, "map", 5, 0, (uint64)mode, size,
167 		virtualAddress, 0, physicalAddress);
168 
169 	if (status != 0) {
170 		dprintf("map_range(base: %p, size: %" B_PRIuSIZE ") "
171 			"mapping failed\n", virtualAddress, size);
172 		return false;
173 	}
174 
175 	return true;
176 }
177 
178 
179 static status_t
180 find_allocated_ranges(void **_exceptionHandlers)
181 {
182 	// we have to preserve the OpenFirmware established mappings
183 	// if we want to continue to use its service after we've
184 	// taken over (we will probably need less translations once
185 	// we have proper driver support for the target hardware).
186 	intptr_t mmu = of_instance_to_package(sMmuInstance);
187 
188 	struct translation_map {
189 		void *PhysicalAddress() {
190 			int64_t p = data;
191 #if 0
192 			// The openboot own "map?" word does not do this, so it must not
193 			// be needed
194 			// Sign extend
195 			p <<= 23;
196 			p >>= 23;
197 #endif
198 
199 			// Keep only PA[40:13]
200 			// FIXME later CPUs have some more bits here
201 			p &= 0x000001FFFFFFE000ll;
202 
203 			return (void*)p;
204 		}
205 
206 		int16_t Mode() {
207 			int16_t mode;
208 			if (data & 2)
209 				mode = PAGE_READ_WRITE;
210 			else
211 				mode = PAGE_READ_ONLY;
212 			return mode;
213 		}
214 
215 		void	*virtual_address;
216 		intptr_t length;
217 		intptr_t data;
218 	} translations[64];
219 
220 	int length = of_getprop(mmu, "translations", &translations,
221 		sizeof(translations));
222 	if (length == OF_FAILED) {
223 		dprintf("Error: no OF translations.\n");
224 		return B_ERROR;
225 	}
226 	length = length / sizeof(struct translation_map);
227 	uint32 total = 0;
228 	TRACE("found %d translations\n", length);
229 
230 	for (int i = 0; i < length; i++) {
231 		struct translation_map *map = &translations[i];
232 		bool keepRange = true;
233 		TRACE("%i: map: %p, length %ld -> phy %p mode %d: ", i,
234 			map->virtual_address, map->length,
235 			map->PhysicalAddress(), map->Mode());
236 
237 		// insert range in physical allocated, if it points to physical memory
238 
239 		if (is_physical_memory(map->PhysicalAddress())
240 			&& insert_physical_allocated_range((addr_t)map->PhysicalAddress(),
241 				map->length) != B_OK) {
242 			dprintf("cannot map physical allocated range "
243 				"(num ranges = %" B_PRIu32 ")!\n",
244 				gKernelArgs.num_physical_allocated_ranges);
245 			return B_ERROR;
246 		}
247 
248 		// insert range in virtual allocated
249 
250 		if (insert_virtual_allocated_range((addr_t)map->virtual_address,
251 				map->length) != B_OK) {
252 			dprintf("cannot map virtual allocated range "
253 				"(num ranges = %" B_PRIu32 ")!\n",
254 				gKernelArgs.num_virtual_allocated_ranges);
255 		}
256 
257 		// insert range in virtual ranges to keep
258 
259 		if (keepRange) {
260 			TRACE("keeping\n");
261 
262 			if (insert_virtual_range_to_keep(map->virtual_address,
263 					map->length) != B_OK) {
264 				dprintf("cannot map virtual range to keep "
265 					"(num ranges = %" B_PRIu32 ")\n",
266 					gKernelArgs.num_virtual_allocated_ranges);
267 			}
268 		} else {
269 			TRACE("dropping\n");
270 		}
271 
272 		total += map->length;
273 	}
274 	TRACE("total size kept: %" B_PRIu32 "\n", total);
275 
276 	// remove the boot loader code from the virtual ranges to keep in the
277 	// kernel
278 	if (remove_virtual_range_to_keep(&__text_begin, &_end - &__text_begin)
279 			!= B_OK) {
280 		dprintf("%s: Failed to remove boot loader range "
281 			"from virtual ranges to keep.\n", __func__);
282 	}
283 
284 	return B_OK;
285 }
286 
287 
288 static void *
289 find_physical_memory_range(size_t size)
290 {
291 	for (uint32 i = 0; i < gKernelArgs.num_physical_memory_ranges; i++) {
292 		if (gKernelArgs.physical_memory_range[i].size > size)
293 			return (void *)(addr_t)gKernelArgs.physical_memory_range[i].start;
294 	}
295 	return PHYSINVAL;
296 }
297 
298 
299 static void *
300 find_free_physical_range(size_t size)
301 {
302 	// just do a simple linear search at the end of the allocated
303 	// ranges (dumb memory allocation)
304 	if (gKernelArgs.num_physical_allocated_ranges == 0) {
305 		if (gKernelArgs.num_physical_memory_ranges == 0)
306 			return PHYSINVAL;
307 
308 		return find_physical_memory_range(size);
309 	}
310 
311 	for (uint32 i = 0; i < gKernelArgs.num_physical_allocated_ranges; i++) {
312 		void *address
313 			= (void *)(addr_t)(gKernelArgs.physical_allocated_range[i].start
314 				+ gKernelArgs.physical_allocated_range[i].size);
315 		if (!is_physical_allocated(address, size)
316 			&& is_physical_memory(address, size)) {
317 			return address;
318 		}
319 	}
320 	return PHYSINVAL;
321 }
322 
323 
324 static void *
325 find_free_virtual_range(void *base, size_t size)
326 {
327 	if (base && !is_virtual_allocated(base, size))
328 		return base;
329 
330 	void *firstFound = NULL;
331 	void *firstBaseFound = NULL;
332 	for (uint32 i = 0; i < gKernelArgs.num_virtual_allocated_ranges; i++) {
333 		void *address
334 			= (void *)(addr_t)(gKernelArgs.virtual_allocated_range[i].start
335 				+ gKernelArgs.virtual_allocated_range[i].size);
336 		if (!is_virtual_allocated(address, size)) {
337 			if (!base)
338 				return address;
339 
340 			if (firstFound == NULL)
341 				firstFound = address;
342 			if (address >= base
343 				&& (firstBaseFound == NULL || address < firstBaseFound)) {
344 				firstBaseFound = address;
345 			}
346 		}
347 	}
348 	return (firstBaseFound ? firstBaseFound : firstFound);
349 }
350 
351 
352 extern "C" void *
353 arch_mmu_allocate(void *_virtualAddress, size_t size, uint8 _protection,
354 	bool exactAddress)
355 {
356 	// we only know page sizes
357 	size = ROUNDUP(size, B_PAGE_SIZE);
358 
359 	uint8 protection = 0;
360 	if (_protection & B_WRITE_AREA)
361 		protection = PAGE_READ_WRITE;
362 	else
363 		protection = PAGE_READ_ONLY;
364 
365 	// If no address is given, use the KERNEL_BASE as base address, since
366 	// that avoids trouble in the kernel, when we decide to keep the region.
367 	void *virtualAddress = _virtualAddress;
368 #if 0
369 	if (!virtualAddress)
370 		virtualAddress = (void*)KERNEL_BASE;
371 #endif
372 
373 	// find free address large enough to hold "size"
374 	virtualAddress = find_free_virtual_range(virtualAddress, size);
375 	if (virtualAddress == NULL)
376 		return NULL;
377 
378 	// fail if the exact address was requested, but is not free
379 	if (exactAddress && _virtualAddress && virtualAddress != _virtualAddress) {
380 		dprintf("arch_mmu_allocate(): exact address requested, but virtual "
381 			"range (base: %p, size: %" B_PRIuSIZE ") is not free.\n",
382 			_virtualAddress, size);
383 		return NULL;
384 	}
385 
386 #if 0
387 	intptr_t status;
388 
389 	/* claim the address */
390 	status = of_call_method(sMmuInstance, "claim", 3, 1, 0, size,
391 		virtualAddress, &_virtualAddress);
392 	if (status != 0) {
393 		dprintf("arch_mmu_allocate(base: %p, size: %" B_PRIuSIZE ") "
394 			"failed to claim virtual address\n", virtualAddress, size);
395 		return NULL;
396 	}
397 
398 #endif
399 	// we have a free virtual range for the allocation, now
400 	// have a look for free physical memory as well (we assume
401 	// that a) there is enough memory, and b) failing is fatal
402 	// so that we don't have to optimize for these cases :)
403 
404 	void *physicalAddress = find_free_physical_range(size);
405 	if (physicalAddress == PHYSINVAL) {
406 		dprintf("arch_mmu_allocate(base: %p, size: %" B_PRIuSIZE ") "
407 			"no free physical address\n", virtualAddress, size);
408 		return NULL;
409 	}
410 
411 	// everything went fine, so lets mark the space as used.
412 
413 #if 0
414 	void* _physicalAddress;
415 	status = of_call_method(sMemoryInstance, "claim", 3, 1, physicalAddress,
416 		1, size, &_physicalAddress);
417 
418 	if (status != 0) {
419 		dprintf("arch_mmu_allocate(base: %p, size: %" B_PRIuSIZE ") "
420 			"failed to claim physical address\n", physicalAddress, size);
421 		return NULL;
422 	}
423 #endif
424 
425 	insert_virtual_allocated_range((addr_t)virtualAddress, size);
426 	insert_physical_allocated_range((addr_t)physicalAddress, size);
427 
428 	if (!map_range(virtualAddress, physicalAddress, size, protection))
429 		return NULL;
430 
431 	return virtualAddress;
432 }
433 
434 
435 extern "C" status_t
436 arch_mmu_free(void *address, size_t size)
437 {
438 	// TODO: implement freeing a region!
439 	return B_OK;
440 }
441 
442 
443 //	#pragma mark - OpenFirmware callbacks and public API
444 
445 
446 #if 0
447 static int
448 map_callback(struct of_arguments *args)
449 {
450 	void *physicalAddress = (void *)args->Argument(0);
451 	void *virtualAddress = (void *)args->Argument(1);
452 	int length = args->Argument(2);
453 	int mode = args->Argument(3);
454 	intptr_t &error = args->ReturnValue(0);
455 
456 	// insert range in physical allocated if needed
457 
458 	if (is_physical_memory(physicalAddress)
459 		&& insert_physical_allocated_range((addr_t)physicalAddress, length)
460 			!= B_OK) {
461 		error = -1;
462 		return OF_FAILED;
463 	}
464 
465 	// insert range in virtual allocated
466 
467 	if (insert_virtual_allocated_range((addr_t)virtualAddress, length)
468 			!= B_OK) {
469 		error = -2;
470 		return OF_FAILED;
471 	}
472 
473 	// map range into the page table
474 
475 	map_range(virtualAddress, physicalAddress, length, mode);
476 
477 	return B_OK;
478 }
479 
480 
481 static int
482 unmap_callback(struct of_arguments *args)
483 {
484 /*	void *address = (void *)args->Argument(0);
485 	int length = args->Argument(1);
486 	int &error = args->ReturnValue(0);
487 */
488 	// TODO: to be implemented
489 
490 	return OF_FAILED;
491 }
492 
493 
494 static int
495 translate_callback(struct of_arguments *args)
496 {
497 	// could not find the translation
498 	return OF_FAILED;
499 }
500 
501 
502 static int
503 alloc_real_mem_callback(struct of_arguments *args)
504 {
505 /*	addr_t minAddress = (addr_t)args->Argument(0);
506 	addr_t maxAddress = (addr_t)args->Argument(1);
507 	int length = args->Argument(2);
508 	int mode = args->Argument(3);
509 	int &error = args->ReturnValue(0);
510 	int &physicalAddress = args->ReturnValue(1);
511 */
512 	// ToDo: to be implemented
513 
514 	return OF_FAILED;
515 }
516 
517 
518 /** Dispatches the callback to the responsible function */
519 
520 static int
521 callback(struct of_arguments *args)
522 {
523 	const char *name = args->name;
524 	TRACE("OF CALLBACK: %s\n", name);
525 
526 	if (!strcmp(name, "map"))
527 		return map_callback(args);
528 	else if (!strcmp(name, "unmap"))
529 		return unmap_callback(args);
530 	else if (!strcmp(name, "translate"))
531 		return translate_callback(args);
532 	else if (!strcmp(name, "alloc-real-mem"))
533 		return alloc_real_mem_callback(args);
534 
535 	return OF_FAILED;
536 }
537 #endif
538 
539 
540 extern "C" status_t
541 arch_set_callback(void)
542 {
543 #if 0
544 	// set OpenFirmware callbacks - it will ask us for memory after that
545 	// instead of maintaining it itself
546 
547 	void *oldCallback = NULL;
548 	if (of_call_client_function("set-callback", 1, 1, &callback, &oldCallback)
549 			== OF_FAILED) {
550 		dprintf("Error: OpenFirmware set-callback failed\n");
551 		return B_ERROR;
552 	}
553 	TRACE("old callback = %p; new callback = %p\n", oldCallback, callback);
554 #endif
555 
556 	return B_OK;
557 }
558 
559 
560 extern "C" status_t
561 arch_mmu_init(void)
562 {
563 	if (of_getprop(gChosen, "mmu", &sMmuInstance, sizeof(int)) == OF_FAILED) {
564 		dprintf("%s: Error: no OpenFirmware mmu\n", __func__);
565 		return B_ERROR;
566 	}
567 
568 	if (of_getprop(gChosen, "memory", &sMemoryInstance, sizeof(int)) == OF_FAILED) {
569 		dprintf("%s: Error: no OpenFirmware memory\n", __func__);
570 		return B_ERROR;
571 	}
572 	// get map of physical memory (fill in kernel_args structure)
573 
574 	size_t total;
575 	if (find_physical_memory_ranges(total) != B_OK) {
576 		dprintf("Error: could not find physical memory ranges!\n");
577 		return B_ERROR;
578 	}
579 	TRACE("total physical memory = %luMB\n", total / (1024 * 1024));
580 
581 	void *exceptionHandlers = (void *)-1;
582 	if (find_allocated_ranges(&exceptionHandlers) != B_OK) {
583 		dprintf("Error: find_allocated_ranges() failed\n");
584 		return B_ERROR;
585 	}
586 
587 #if 0
588 	if (exceptionHandlers == (void *)-1) {
589 		// TODO: create mapping for the exception handlers
590 		dprintf("Error: no mapping for the exception handlers!\n");
591 	}
592 
593 	// Set the Open Firmware memory callback. From now on the Open Firmware
594 	// will ask us for memory.
595 	arch_set_callback();
596 
597 	// set up new page table and turn on translation again
598 	// TODO "set up new page table and turn on translation again" (see PPC)
599 #endif
600 
601 	// set kernel args
602 
603 	TRACE("virt_allocated: %" B_PRIu32 "\n",
604 		gKernelArgs.num_virtual_allocated_ranges);
605 	TRACE("phys_allocated: %" B_PRIu32 "\n",
606 		gKernelArgs.num_physical_allocated_ranges);
607 	TRACE("phys_memory: %" B_PRIu32 "\n",
608 		gKernelArgs.num_physical_memory_ranges);
609 
610 #if 0
611 	// TODO set gKernelArgs.arch_args content if we have something to put in there
612 	gKernelArgs.arch_args.page_table.start = (addr_t)sPageTable;
613 	gKernelArgs.arch_args.page_table.size = tableSize;
614 
615 	gKernelArgs.arch_args.exception_handlers.start = (addr_t)exceptionHandlers;
616 	gKernelArgs.arch_args.exception_handlers.size = B_PAGE_SIZE;
617 #endif
618 
619 	return B_OK;
620 }
621 
622