xref: /openbmc/linux/drivers/char/agp/uninorth-agp.c (revision a44e4f3a)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * UniNorth AGPGART routines.
4  */
5 #include <linux/module.h>
6 #include <linux/pci.h>
7 #include <linux/slab.h>
8 #include <linux/init.h>
9 #include <linux/pagemap.h>
10 #include <linux/agp_backend.h>
11 #include <linux/delay.h>
12 #include <linux/vmalloc.h>
13 #include <asm/uninorth.h>
14 #include <asm/prom.h>
15 #include <asm/pmac_feature.h>
16 #include "agp.h"
17 
18 /*
19  * NOTES for uninorth3 (G5 AGP) supports :
20  *
21  * There maybe also possibility to have bigger cache line size for
22  * agp (see pmac_pci.c and look for cache line). Need to be investigated
23  * by someone.
24  *
25  * PAGE size are hardcoded but this may change, see asm/page.h.
26  *
27  * Jerome Glisse <j.glisse@gmail.com>
28  */
29 static int uninorth_rev;
30 static int is_u3;
31 static u32 scratch_value;
32 
33 #define DEFAULT_APERTURE_SIZE 256
34 #define DEFAULT_APERTURE_STRING "256"
35 static char *aperture = NULL;
36 
37 static int uninorth_fetch_size(void)
38 {
39 	int i, size = 0;
40 	struct aper_size_info_32 *values =
41 	    A_SIZE_32(agp_bridge->driver->aperture_sizes);
42 
43 	if (aperture) {
44 		char *save = aperture;
45 
46 		size = memparse(aperture, &aperture) >> 20;
47 		aperture = save;
48 
49 		for (i = 0; i < agp_bridge->driver->num_aperture_sizes; i++)
50 			if (size == values[i].size)
51 				break;
52 
53 		if (i == agp_bridge->driver->num_aperture_sizes) {
54 			dev_err(&agp_bridge->dev->dev, "invalid aperture size, "
55 				"using default\n");
56 			size = 0;
57 			aperture = NULL;
58 		}
59 	}
60 
61 	if (!size) {
62 		for (i = 0; i < agp_bridge->driver->num_aperture_sizes; i++)
63 			if (values[i].size == DEFAULT_APERTURE_SIZE)
64 				break;
65 	}
66 
67 	agp_bridge->previous_size =
68 	    agp_bridge->current_size = (void *)(values + i);
69 	agp_bridge->aperture_size_idx = i;
70 	return values[i].size;
71 }
72 
73 static void uninorth_tlbflush(struct agp_memory *mem)
74 {
75 	u32 ctrl = UNI_N_CFG_GART_ENABLE;
76 
77 	if (is_u3)
78 		ctrl |= U3_N_CFG_GART_PERFRD;
79 	pci_write_config_dword(agp_bridge->dev, UNI_N_CFG_GART_CTRL,
80 			       ctrl | UNI_N_CFG_GART_INVAL);
81 	pci_write_config_dword(agp_bridge->dev, UNI_N_CFG_GART_CTRL, ctrl);
82 
83 	if (!mem && uninorth_rev <= 0x30) {
84 		pci_write_config_dword(agp_bridge->dev, UNI_N_CFG_GART_CTRL,
85 				       ctrl | UNI_N_CFG_GART_2xRESET);
86 		pci_write_config_dword(agp_bridge->dev, UNI_N_CFG_GART_CTRL,
87 				       ctrl);
88 	}
89 }
90 
91 static void uninorth_cleanup(void)
92 {
93 	u32 tmp;
94 
95 	pci_read_config_dword(agp_bridge->dev, UNI_N_CFG_GART_CTRL, &tmp);
96 	if (!(tmp & UNI_N_CFG_GART_ENABLE))
97 		return;
98 	tmp |= UNI_N_CFG_GART_INVAL;
99 	pci_write_config_dword(agp_bridge->dev, UNI_N_CFG_GART_CTRL, tmp);
100 	pci_write_config_dword(agp_bridge->dev, UNI_N_CFG_GART_CTRL, 0);
101 
102 	if (uninorth_rev <= 0x30) {
103 		pci_write_config_dword(agp_bridge->dev, UNI_N_CFG_GART_CTRL,
104 				       UNI_N_CFG_GART_2xRESET);
105 		pci_write_config_dword(agp_bridge->dev, UNI_N_CFG_GART_CTRL,
106 				       0);
107 	}
108 }
109 
110 static int uninorth_configure(void)
111 {
112 	struct aper_size_info_32 *current_size;
113 
114 	current_size = A_SIZE_32(agp_bridge->current_size);
115 
116 	dev_info(&agp_bridge->dev->dev, "configuring for size idx: %d\n",
117 		 current_size->size_value);
118 
119 	/* aperture size and gatt addr */
120 	pci_write_config_dword(agp_bridge->dev,
121 		UNI_N_CFG_GART_BASE,
122 		(agp_bridge->gatt_bus_addr & 0xfffff000)
123 			| current_size->size_value);
124 
125 	/* HACK ALERT
126 	 * UniNorth seem to be buggy enough not to handle properly when
127 	 * the AGP aperture isn't mapped at bus physical address 0
128 	 */
129 	agp_bridge->gart_bus_addr = 0;
130 #ifdef CONFIG_PPC64
131 	/* Assume U3 or later on PPC64 systems */
132 	/* high 4 bits of GART physical address go in UNI_N_CFG_AGP_BASE */
133 	pci_write_config_dword(agp_bridge->dev, UNI_N_CFG_AGP_BASE,
134 			       (agp_bridge->gatt_bus_addr >> 32) & 0xf);
135 #else
136 	pci_write_config_dword(agp_bridge->dev,
137 		UNI_N_CFG_AGP_BASE, agp_bridge->gart_bus_addr);
138 #endif
139 
140 	if (is_u3) {
141 		pci_write_config_dword(agp_bridge->dev,
142 				       UNI_N_CFG_GART_DUMMY_PAGE,
143 				       page_to_phys(agp_bridge->scratch_page_page) >> 12);
144 	}
145 
146 	return 0;
147 }
148 
149 static int uninorth_insert_memory(struct agp_memory *mem, off_t pg_start, int type)
150 {
151 	int i, num_entries;
152 	void *temp;
153 	u32 *gp;
154 	int mask_type;
155 
156 	if (type != mem->type)
157 		return -EINVAL;
158 
159 	mask_type = agp_bridge->driver->agp_type_to_mask_type(agp_bridge, type);
160 	if (mask_type != 0) {
161 		/* We know nothing of memory types */
162 		return -EINVAL;
163 	}
164 
165 	if (mem->page_count == 0)
166 		return 0;
167 
168 	temp = agp_bridge->current_size;
169 	num_entries = A_SIZE_32(temp)->num_entries;
170 
171 	if ((pg_start + mem->page_count) > num_entries)
172 		return -EINVAL;
173 
174 	gp = (u32 *) &agp_bridge->gatt_table[pg_start];
175 	for (i = 0; i < mem->page_count; ++i) {
176 		if (gp[i] != scratch_value) {
177 			dev_info(&agp_bridge->dev->dev,
178 				 "uninorth_insert_memory: entry 0x%x occupied (%x)\n",
179 				 i, gp[i]);
180 			return -EBUSY;
181 		}
182 	}
183 
184 	for (i = 0; i < mem->page_count; i++) {
185 		if (is_u3)
186 			gp[i] = (page_to_phys(mem->pages[i]) >> PAGE_SHIFT) | 0x80000000UL;
187 		else
188 			gp[i] =	cpu_to_le32((page_to_phys(mem->pages[i]) & 0xFFFFF000UL) |
189 					    0x1UL);
190 		flush_dcache_range((unsigned long)__va(page_to_phys(mem->pages[i])),
191 				   (unsigned long)__va(page_to_phys(mem->pages[i]))+0x1000);
192 	}
193 	mb();
194 	uninorth_tlbflush(mem);
195 
196 	return 0;
197 }
198 
199 static int uninorth_remove_memory(struct agp_memory *mem, off_t pg_start, int type)
200 {
201 	size_t i;
202 	u32 *gp;
203 	int mask_type;
204 
205 	if (type != mem->type)
206 		return -EINVAL;
207 
208 	mask_type = agp_bridge->driver->agp_type_to_mask_type(agp_bridge, type);
209 	if (mask_type != 0) {
210 		/* We know nothing of memory types */
211 		return -EINVAL;
212 	}
213 
214 	if (mem->page_count == 0)
215 		return 0;
216 
217 	gp = (u32 *) &agp_bridge->gatt_table[pg_start];
218 	for (i = 0; i < mem->page_count; ++i) {
219 		gp[i] = scratch_value;
220 	}
221 	mb();
222 	uninorth_tlbflush(mem);
223 
224 	return 0;
225 }
226 
227 static void uninorth_agp_enable(struct agp_bridge_data *bridge, u32 mode)
228 {
229 	u32 command, scratch, status;
230 	int timeout;
231 
232 	pci_read_config_dword(bridge->dev,
233 			      bridge->capndx + PCI_AGP_STATUS,
234 			      &status);
235 
236 	command = agp_collect_device_status(bridge, mode, status);
237 	command |= PCI_AGP_COMMAND_AGP;
238 
239 	if (uninorth_rev == 0x21) {
240 		/*
241 		 * Darwin disable AGP 4x on this revision, thus we
242 		 * may assume it's broken. This is an AGP2 controller.
243 		 */
244 		command &= ~AGPSTAT2_4X;
245 	}
246 
247 	if ((uninorth_rev >= 0x30) && (uninorth_rev <= 0x33)) {
248 		/*
249 		 * We need to set REQ_DEPTH to 7 for U3 versions 1.0, 2.1,
250 		 * 2.2 and 2.3, Darwin do so.
251 		 */
252 		if ((command >> AGPSTAT_RQ_DEPTH_SHIFT) > 7)
253 			command = (command & ~AGPSTAT_RQ_DEPTH)
254 				| (7 << AGPSTAT_RQ_DEPTH_SHIFT);
255 	}
256 
257 	uninorth_tlbflush(NULL);
258 
259 	timeout = 0;
260 	do {
261 		pci_write_config_dword(bridge->dev,
262 				       bridge->capndx + PCI_AGP_COMMAND,
263 				       command);
264 		pci_read_config_dword(bridge->dev,
265 				      bridge->capndx + PCI_AGP_COMMAND,
266 				       &scratch);
267 	} while ((scratch & PCI_AGP_COMMAND_AGP) == 0 && ++timeout < 1000);
268 	if ((scratch & PCI_AGP_COMMAND_AGP) == 0)
269 		dev_err(&bridge->dev->dev, "can't write UniNorth AGP "
270 			"command register\n");
271 
272 	if (uninorth_rev >= 0x30) {
273 		/* This is an AGP V3 */
274 		agp_device_command(command, (status & AGPSTAT_MODE_3_0) != 0);
275 	} else {
276 		/* AGP V2 */
277 		agp_device_command(command, false);
278 	}
279 
280 	uninorth_tlbflush(NULL);
281 }
282 
283 #ifdef CONFIG_PM
284 /*
285  * These Power Management routines are _not_ called by the normal PCI PM layer,
286  * but directly by the video driver through function pointers in the device
287  * tree.
288  */
289 static int agp_uninorth_suspend(struct pci_dev *pdev)
290 {
291 	struct agp_bridge_data *bridge;
292 	u32 cmd;
293 	u8 agp;
294 	struct pci_dev *device = NULL;
295 
296 	bridge = agp_find_bridge(pdev);
297 	if (bridge == NULL)
298 		return -ENODEV;
299 
300 	/* Only one suspend supported */
301 	if (bridge->dev_private_data)
302 		return 0;
303 
304 	/* turn off AGP on the video chip, if it was enabled */
305 	for_each_pci_dev(device) {
306 		/* Don't touch the bridge yet, device first */
307 		if (device == pdev)
308 			continue;
309 		/* Only deal with devices on the same bus here, no Mac has a P2P
310 		 * bridge on the AGP port, and mucking around the entire PCI
311 		 * tree is source of problems on some machines because of a bug
312 		 * in some versions of pci_find_capability() when hitting a dead
313 		 * device
314 		 */
315 		if (device->bus != pdev->bus)
316 			continue;
317 		agp = pci_find_capability(device, PCI_CAP_ID_AGP);
318 		if (!agp)
319 			continue;
320 		pci_read_config_dword(device, agp + PCI_AGP_COMMAND, &cmd);
321 		if (!(cmd & PCI_AGP_COMMAND_AGP))
322 			continue;
323 		dev_info(&pdev->dev, "disabling AGP on device %s\n",
324 			 pci_name(device));
325 		cmd &= ~PCI_AGP_COMMAND_AGP;
326 		pci_write_config_dword(device, agp + PCI_AGP_COMMAND, cmd);
327 	}
328 
329 	/* turn off AGP on the bridge */
330 	agp = pci_find_capability(pdev, PCI_CAP_ID_AGP);
331 	pci_read_config_dword(pdev, agp + PCI_AGP_COMMAND, &cmd);
332 	bridge->dev_private_data = (void *)(long)cmd;
333 	if (cmd & PCI_AGP_COMMAND_AGP) {
334 		dev_info(&pdev->dev, "disabling AGP on bridge\n");
335 		cmd &= ~PCI_AGP_COMMAND_AGP;
336 		pci_write_config_dword(pdev, agp + PCI_AGP_COMMAND, cmd);
337 	}
338 	/* turn off the GART */
339 	uninorth_cleanup();
340 
341 	return 0;
342 }
343 
344 static int agp_uninorth_resume(struct pci_dev *pdev)
345 {
346 	struct agp_bridge_data *bridge;
347 	u32 command;
348 
349 	bridge = agp_find_bridge(pdev);
350 	if (bridge == NULL)
351 		return -ENODEV;
352 
353 	command = (long)bridge->dev_private_data;
354 	bridge->dev_private_data = NULL;
355 	if (!(command & PCI_AGP_COMMAND_AGP))
356 		return 0;
357 
358 	uninorth_agp_enable(bridge, command);
359 
360 	return 0;
361 }
362 #endif /* CONFIG_PM */
363 
364 static struct {
365 	struct page **pages_arr;
366 } uninorth_priv;
367 
368 static int uninorth_create_gatt_table(struct agp_bridge_data *bridge)
369 {
370 	char *table;
371 	char *table_end;
372 	int size;
373 	int page_order;
374 	int num_entries;
375 	int i;
376 	void *temp;
377 	struct page *page;
378 
379 	/* We can't handle 2 level gatt's */
380 	if (bridge->driver->size_type == LVL2_APER_SIZE)
381 		return -EINVAL;
382 
383 	table = NULL;
384 	i = bridge->aperture_size_idx;
385 	temp = bridge->current_size;
386 	size = page_order = num_entries = 0;
387 
388 	do {
389 		size = A_SIZE_32(temp)->size;
390 		page_order = A_SIZE_32(temp)->page_order;
391 		num_entries = A_SIZE_32(temp)->num_entries;
392 
393 		table = (char *) __get_free_pages(GFP_KERNEL, page_order);
394 
395 		if (table == NULL) {
396 			i++;
397 			bridge->current_size = A_IDX32(bridge);
398 		} else {
399 			bridge->aperture_size_idx = i;
400 		}
401 	} while (!table && (i < bridge->driver->num_aperture_sizes));
402 
403 	if (table == NULL)
404 		return -ENOMEM;
405 
406 	uninorth_priv.pages_arr = kmalloc_array(1 << page_order,
407 						sizeof(struct page *),
408 						GFP_KERNEL);
409 	if (uninorth_priv.pages_arr == NULL)
410 		goto enomem;
411 
412 	table_end = table + ((PAGE_SIZE * (1 << page_order)) - 1);
413 
414 	for (page = virt_to_page(table), i = 0; page <= virt_to_page(table_end);
415 	     page++, i++) {
416 		SetPageReserved(page);
417 		uninorth_priv.pages_arr[i] = page;
418 	}
419 
420 	bridge->gatt_table_real = (u32 *) table;
421 	/* Need to clear out any dirty data still sitting in caches */
422 	flush_dcache_range((unsigned long)table,
423 			   (unsigned long)table_end + 1);
424 	bridge->gatt_table = vmap(uninorth_priv.pages_arr, (1 << page_order), 0, PAGE_KERNEL_NCG);
425 
426 	if (bridge->gatt_table == NULL)
427 		goto enomem;
428 
429 	bridge->gatt_bus_addr = virt_to_phys(table);
430 
431 	if (is_u3)
432 		scratch_value = (page_to_phys(agp_bridge->scratch_page_page) >> PAGE_SHIFT) | 0x80000000UL;
433 	else
434 		scratch_value =	cpu_to_le32((page_to_phys(agp_bridge->scratch_page_page) & 0xFFFFF000UL) |
435 				0x1UL);
436 	for (i = 0; i < num_entries; i++)
437 		bridge->gatt_table[i] = scratch_value;
438 
439 	return 0;
440 
441 enomem:
442 	kfree(uninorth_priv.pages_arr);
443 	if (table)
444 		free_pages((unsigned long)table, page_order);
445 	return -ENOMEM;
446 }
447 
448 static int uninorth_free_gatt_table(struct agp_bridge_data *bridge)
449 {
450 	int page_order;
451 	char *table, *table_end;
452 	void *temp;
453 	struct page *page;
454 
455 	temp = bridge->current_size;
456 	page_order = A_SIZE_32(temp)->page_order;
457 
458 	/* Do not worry about freeing memory, because if this is
459 	 * called, then all agp memory is deallocated and removed
460 	 * from the table.
461 	 */
462 
463 	vunmap(bridge->gatt_table);
464 	kfree(uninorth_priv.pages_arr);
465 	table = (char *) bridge->gatt_table_real;
466 	table_end = table + ((PAGE_SIZE * (1 << page_order)) - 1);
467 
468 	for (page = virt_to_page(table); page <= virt_to_page(table_end); page++)
469 		ClearPageReserved(page);
470 
471 	free_pages((unsigned long) bridge->gatt_table_real, page_order);
472 
473 	return 0;
474 }
475 
476 static void null_cache_flush(void)
477 {
478 	mb();
479 }
480 
481 /* Setup function */
482 
483 static const struct aper_size_info_32 uninorth_sizes[] =
484 {
485 	{256, 65536, 6, 64},
486 	{128, 32768, 5, 32},
487 	{64, 16384, 4, 16},
488 	{32, 8192, 3, 8},
489 	{16, 4096, 2, 4},
490 	{8, 2048, 1, 2},
491 	{4, 1024, 0, 1}
492 };
493 
494 /*
495  * Not sure that u3 supports that high aperture sizes but it
496  * would strange if it did not :)
497  */
498 static const struct aper_size_info_32 u3_sizes[] =
499 {
500 	{512, 131072, 7, 128},
501 	{256, 65536, 6, 64},
502 	{128, 32768, 5, 32},
503 	{64, 16384, 4, 16},
504 	{32, 8192, 3, 8},
505 	{16, 4096, 2, 4},
506 	{8, 2048, 1, 2},
507 	{4, 1024, 0, 1}
508 };
509 
510 const struct agp_bridge_driver uninorth_agp_driver = {
511 	.owner			= THIS_MODULE,
512 	.aperture_sizes		= (void *)uninorth_sizes,
513 	.size_type		= U32_APER_SIZE,
514 	.num_aperture_sizes	= ARRAY_SIZE(uninorth_sizes),
515 	.configure		= uninorth_configure,
516 	.fetch_size		= uninorth_fetch_size,
517 	.cleanup		= uninorth_cleanup,
518 	.tlb_flush		= uninorth_tlbflush,
519 	.mask_memory		= agp_generic_mask_memory,
520 	.masks			= NULL,
521 	.cache_flush		= null_cache_flush,
522 	.agp_enable		= uninorth_agp_enable,
523 	.create_gatt_table	= uninorth_create_gatt_table,
524 	.free_gatt_table	= uninorth_free_gatt_table,
525 	.insert_memory		= uninorth_insert_memory,
526 	.remove_memory		= uninorth_remove_memory,
527 	.alloc_by_type		= agp_generic_alloc_by_type,
528 	.free_by_type		= agp_generic_free_by_type,
529 	.agp_alloc_page		= agp_generic_alloc_page,
530 	.agp_alloc_pages	= agp_generic_alloc_pages,
531 	.agp_destroy_page	= agp_generic_destroy_page,
532 	.agp_destroy_pages	= agp_generic_destroy_pages,
533 	.agp_type_to_mask_type  = agp_generic_type_to_mask_type,
534 	.cant_use_aperture	= true,
535 	.needs_scratch_page	= true,
536 };
537 
538 const struct agp_bridge_driver u3_agp_driver = {
539 	.owner			= THIS_MODULE,
540 	.aperture_sizes		= (void *)u3_sizes,
541 	.size_type		= U32_APER_SIZE,
542 	.num_aperture_sizes	= ARRAY_SIZE(u3_sizes),
543 	.configure		= uninorth_configure,
544 	.fetch_size		= uninorth_fetch_size,
545 	.cleanup		= uninorth_cleanup,
546 	.tlb_flush		= uninorth_tlbflush,
547 	.mask_memory		= agp_generic_mask_memory,
548 	.masks			= NULL,
549 	.cache_flush		= null_cache_flush,
550 	.agp_enable		= uninorth_agp_enable,
551 	.create_gatt_table	= uninorth_create_gatt_table,
552 	.free_gatt_table	= uninorth_free_gatt_table,
553 	.insert_memory		= uninorth_insert_memory,
554 	.remove_memory		= uninorth_remove_memory,
555 	.alloc_by_type		= agp_generic_alloc_by_type,
556 	.free_by_type		= agp_generic_free_by_type,
557 	.agp_alloc_page		= agp_generic_alloc_page,
558 	.agp_alloc_pages	= agp_generic_alloc_pages,
559 	.agp_destroy_page	= agp_generic_destroy_page,
560 	.agp_destroy_pages	= agp_generic_destroy_pages,
561 	.agp_type_to_mask_type  = agp_generic_type_to_mask_type,
562 	.cant_use_aperture	= true,
563 	.needs_scratch_page	= true,
564 };
565 
566 static struct agp_device_ids uninorth_agp_device_ids[] = {
567 	{
568 		.device_id	= PCI_DEVICE_ID_APPLE_UNI_N_AGP,
569 		.chipset_name	= "UniNorth",
570 	},
571 	{
572 		.device_id	= PCI_DEVICE_ID_APPLE_UNI_N_AGP_P,
573 		.chipset_name	= "UniNorth/Pangea",
574 	},
575 	{
576 		.device_id	= PCI_DEVICE_ID_APPLE_UNI_N_AGP15,
577 		.chipset_name	= "UniNorth 1.5",
578 	},
579 	{
580 		.device_id	= PCI_DEVICE_ID_APPLE_UNI_N_AGP2,
581 		.chipset_name	= "UniNorth 2",
582 	},
583 	{
584 		.device_id	= PCI_DEVICE_ID_APPLE_U3_AGP,
585 		.chipset_name	= "U3",
586 	},
587 	{
588 		.device_id	= PCI_DEVICE_ID_APPLE_U3L_AGP,
589 		.chipset_name	= "U3L",
590 	},
591 	{
592 		.device_id	= PCI_DEVICE_ID_APPLE_U3H_AGP,
593 		.chipset_name	= "U3H",
594 	},
595 	{
596 		.device_id	= PCI_DEVICE_ID_APPLE_IPID2_AGP,
597 		.chipset_name	= "UniNorth/Intrepid2",
598 	},
599 };
600 
601 static int agp_uninorth_probe(struct pci_dev *pdev,
602 			      const struct pci_device_id *ent)
603 {
604 	struct agp_device_ids *devs = uninorth_agp_device_ids;
605 	struct agp_bridge_data *bridge;
606 	struct device_node *uninorth_node;
607 	u8 cap_ptr;
608 	int j;
609 
610 	cap_ptr = pci_find_capability(pdev, PCI_CAP_ID_AGP);
611 	if (cap_ptr == 0)
612 		return -ENODEV;
613 
614 	/* probe for known chipsets */
615 	for (j = 0; devs[j].chipset_name != NULL; ++j) {
616 		if (pdev->device == devs[j].device_id) {
617 			dev_info(&pdev->dev, "Apple %s chipset\n",
618 				 devs[j].chipset_name);
619 			goto found;
620 		}
621 	}
622 
623 	dev_err(&pdev->dev, "unsupported Apple chipset [%04x/%04x]\n",
624 		pdev->vendor, pdev->device);
625 	return -ENODEV;
626 
627  found:
628 	/* Set revision to 0 if we could not read it. */
629 	uninorth_rev = 0;
630 	is_u3 = 0;
631 	/* Locate core99 Uni-N */
632 	uninorth_node = of_find_node_by_name(NULL, "uni-n");
633 	/* Locate G5 u3 */
634 	if (uninorth_node == NULL) {
635 		is_u3 = 1;
636 		uninorth_node = of_find_node_by_name(NULL, "u3");
637 	}
638 	if (uninorth_node) {
639 		const int *revprop = of_get_property(uninorth_node,
640 				"device-rev", NULL);
641 		if (revprop != NULL)
642 			uninorth_rev = *revprop & 0x3f;
643 		of_node_put(uninorth_node);
644 	}
645 
646 #ifdef CONFIG_PM
647 	/* Inform platform of our suspend/resume caps */
648 	pmac_register_agp_pm(pdev, agp_uninorth_suspend, agp_uninorth_resume);
649 #endif
650 
651 	/* Allocate & setup our driver */
652 	bridge = agp_alloc_bridge();
653 	if (!bridge)
654 		return -ENOMEM;
655 
656 	if (is_u3)
657 		bridge->driver = &u3_agp_driver;
658 	else
659 		bridge->driver = &uninorth_agp_driver;
660 
661 	bridge->dev = pdev;
662 	bridge->capndx = cap_ptr;
663 	bridge->flags = AGP_ERRATA_FASTWRITES;
664 
665 	/* Fill in the mode register */
666 	pci_read_config_dword(pdev, cap_ptr+PCI_AGP_STATUS, &bridge->mode);
667 
668 	pci_set_drvdata(pdev, bridge);
669 	return agp_add_bridge(bridge);
670 }
671 
672 static void agp_uninorth_remove(struct pci_dev *pdev)
673 {
674 	struct agp_bridge_data *bridge = pci_get_drvdata(pdev);
675 
676 #ifdef CONFIG_PM
677 	/* Inform platform of our suspend/resume caps */
678 	pmac_register_agp_pm(pdev, NULL, NULL);
679 #endif
680 
681 	agp_remove_bridge(bridge);
682 	agp_put_bridge(bridge);
683 }
684 
685 static const struct pci_device_id agp_uninorth_pci_table[] = {
686 	{
687 	.class		= (PCI_CLASS_BRIDGE_HOST << 8),
688 	.class_mask	= ~0,
689 	.vendor		= PCI_VENDOR_ID_APPLE,
690 	.device		= PCI_ANY_ID,
691 	.subvendor	= PCI_ANY_ID,
692 	.subdevice	= PCI_ANY_ID,
693 	},
694 	{ }
695 };
696 
697 MODULE_DEVICE_TABLE(pci, agp_uninorth_pci_table);
698 
699 static struct pci_driver agp_uninorth_pci_driver = {
700 	.name		= "agpgart-uninorth",
701 	.id_table	= agp_uninorth_pci_table,
702 	.probe		= agp_uninorth_probe,
703 	.remove		= agp_uninorth_remove,
704 };
705 
706 static int __init agp_uninorth_init(void)
707 {
708 	if (agp_off)
709 		return -EINVAL;
710 	return pci_register_driver(&agp_uninorth_pci_driver);
711 }
712 
713 static void __exit agp_uninorth_cleanup(void)
714 {
715 	pci_unregister_driver(&agp_uninorth_pci_driver);
716 }
717 
718 module_init(agp_uninorth_init);
719 module_exit(agp_uninorth_cleanup);
720 
721 module_param(aperture, charp, 0);
722 MODULE_PARM_DESC(aperture,
723 		 "Aperture size, must be power of two between 4MB and an\n"
724 		 "\t\tupper limit specific to the UniNorth revision.\n"
725 		 "\t\tDefault: " DEFAULT_APERTURE_STRING "M");
726 
727 MODULE_AUTHOR("Ben Herrenschmidt & Paul Mackerras");
728 MODULE_LICENSE("GPL");
729