xref: /openbmc/linux/drivers/char/agp/hp-agp.c (revision 1da177e4)
1 /*
2  * HP zx1 AGPGART routines.
3  *
4  * (c) Copyright 2002, 2003 Hewlett-Packard Development Company, L.P.
5  *	Bjorn Helgaas <bjorn.helgaas@hp.com>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11 
12 #include <linux/acpi.h>
13 #include <linux/module.h>
14 #include <linux/pci.h>
15 #include <linux/init.h>
16 #include <linux/agp_backend.h>
17 
18 #include <asm/acpi-ext.h>
19 
20 #include "agp.h"
21 
22 #ifndef log2
23 #define log2(x)		ffz(~(x))
24 #endif
25 
26 #define HP_ZX1_IOC_OFFSET	0x1000  /* ACPI reports SBA, we want IOC */
27 
28 /* HP ZX1 IOC registers */
29 #define HP_ZX1_IBASE		0x300
30 #define HP_ZX1_IMASK		0x308
31 #define HP_ZX1_PCOM		0x310
32 #define HP_ZX1_TCNFG		0x318
33 #define HP_ZX1_PDIR_BASE	0x320
34 
35 #define HP_ZX1_IOVA_BASE	GB(1UL)
36 #define HP_ZX1_IOVA_SIZE	GB(1UL)
37 #define HP_ZX1_GART_SIZE	(HP_ZX1_IOVA_SIZE / 2)
38 #define HP_ZX1_SBA_IOMMU_COOKIE	0x0000badbadc0ffeeUL
39 
40 #define HP_ZX1_PDIR_VALID_BIT	0x8000000000000000UL
41 #define HP_ZX1_IOVA_TO_PDIR(va)	((va - hp_private.iova_base) >> hp_private.io_tlb_shift)
42 
43 #define AGP8X_MODE_BIT		3
44 #define AGP8X_MODE		(1 << AGP8X_MODE_BIT)
45 
46 /* AGP bridge need not be PCI device, but DRM thinks it is. */
47 static struct pci_dev fake_bridge_dev;
48 
49 static int hp_zx1_gart_found;
50 
51 static struct aper_size_info_fixed hp_zx1_sizes[] =
52 {
53 	{0, 0, 0},		/* filled in by hp_zx1_fetch_size() */
54 };
55 
56 static struct gatt_mask hp_zx1_masks[] =
57 {
58 	{.mask = HP_ZX1_PDIR_VALID_BIT, .type = 0}
59 };
60 
61 static struct _hp_private {
62 	volatile u8 __iomem *ioc_regs;
63 	volatile u8 __iomem *lba_regs;
64 	int lba_cap_offset;
65 	u64 *io_pdir;		// PDIR for entire IOVA
66 	u64 *gatt;		// PDIR just for GART (subset of above)
67 	u64 gatt_entries;
68 	u64 iova_base;
69 	u64 gart_base;
70 	u64 gart_size;
71 	u64 io_pdir_size;
72 	int io_pdir_owner;	// do we own it, or share it with sba_iommu?
73 	int io_page_size;
74 	int io_tlb_shift;
75 	int io_tlb_ps;		// IOC ps config
76 	int io_pages_per_kpage;
77 } hp_private;
78 
79 static int __init hp_zx1_ioc_shared(void)
80 {
81 	struct _hp_private *hp = &hp_private;
82 
83 	printk(KERN_INFO PFX "HP ZX1 IOC: IOPDIR shared with sba_iommu\n");
84 
85 	/*
86 	 * IOC already configured by sba_iommu module; just use
87 	 * its setup.  We assume:
88 	 * 	- IOVA space is 1Gb in size
89 	 * 	- first 512Mb is IOMMU, second 512Mb is GART
90 	 */
91 	hp->io_tlb_ps = readq(hp->ioc_regs+HP_ZX1_TCNFG);
92 	switch (hp->io_tlb_ps) {
93 		case 0: hp->io_tlb_shift = 12; break;
94 		case 1: hp->io_tlb_shift = 13; break;
95 		case 2: hp->io_tlb_shift = 14; break;
96 		case 3: hp->io_tlb_shift = 16; break;
97 		default:
98 			printk(KERN_ERR PFX "Invalid IOTLB page size "
99 			       "configuration 0x%x\n", hp->io_tlb_ps);
100 			hp->gatt = NULL;
101 			hp->gatt_entries = 0;
102 			return -ENODEV;
103 	}
104 	hp->io_page_size = 1 << hp->io_tlb_shift;
105 	hp->io_pages_per_kpage = PAGE_SIZE / hp->io_page_size;
106 
107 	hp->iova_base = readq(hp->ioc_regs+HP_ZX1_IBASE) & ~0x1;
108 	hp->gart_base = hp->iova_base + HP_ZX1_IOVA_SIZE - HP_ZX1_GART_SIZE;
109 
110 	hp->gart_size = HP_ZX1_GART_SIZE;
111 	hp->gatt_entries = hp->gart_size / hp->io_page_size;
112 
113 	hp->io_pdir = phys_to_virt(readq(hp->ioc_regs+HP_ZX1_PDIR_BASE));
114 	hp->gatt = &hp->io_pdir[HP_ZX1_IOVA_TO_PDIR(hp->gart_base)];
115 
116 	if (hp->gatt[0] != HP_ZX1_SBA_IOMMU_COOKIE) {
117 		/* Normal case when no AGP device in system */
118 	    	hp->gatt = NULL;
119 		hp->gatt_entries = 0;
120 		printk(KERN_ERR PFX "No reserved IO PDIR entry found; "
121 		       "GART disabled\n");
122 		return -ENODEV;
123 	}
124 
125 	return 0;
126 }
127 
128 static int __init
129 hp_zx1_ioc_owner (void)
130 {
131 	struct _hp_private *hp = &hp_private;
132 
133 	printk(KERN_INFO PFX "HP ZX1 IOC: IOPDIR dedicated to GART\n");
134 
135 	/*
136 	 * Select an IOV page size no larger than system page size.
137 	 */
138 	if (PAGE_SIZE >= KB(64)) {
139 		hp->io_tlb_shift = 16;
140 		hp->io_tlb_ps = 3;
141 	} else if (PAGE_SIZE >= KB(16)) {
142 		hp->io_tlb_shift = 14;
143 		hp->io_tlb_ps = 2;
144 	} else if (PAGE_SIZE >= KB(8)) {
145 		hp->io_tlb_shift = 13;
146 		hp->io_tlb_ps = 1;
147 	} else {
148 		hp->io_tlb_shift = 12;
149 		hp->io_tlb_ps = 0;
150 	}
151 	hp->io_page_size = 1 << hp->io_tlb_shift;
152 	hp->io_pages_per_kpage = PAGE_SIZE / hp->io_page_size;
153 
154 	hp->iova_base = HP_ZX1_IOVA_BASE;
155 	hp->gart_size = HP_ZX1_GART_SIZE;
156 	hp->gart_base = hp->iova_base + HP_ZX1_IOVA_SIZE - hp->gart_size;
157 
158 	hp->gatt_entries = hp->gart_size / hp->io_page_size;
159 	hp->io_pdir_size = (HP_ZX1_IOVA_SIZE / hp->io_page_size) * sizeof(u64);
160 
161 	return 0;
162 }
163 
164 static int __init
165 hp_zx1_ioc_init (u64 hpa)
166 {
167 	struct _hp_private *hp = &hp_private;
168 
169 	hp->ioc_regs = ioremap(hpa, 1024);
170 	if (!hp->ioc_regs)
171 		return -ENOMEM;
172 
173 	/*
174 	 * If the IOTLB is currently disabled, we can take it over.
175 	 * Otherwise, we have to share with sba_iommu.
176 	 */
177 	hp->io_pdir_owner = (readq(hp->ioc_regs+HP_ZX1_IBASE) & 0x1) == 0;
178 
179 	if (hp->io_pdir_owner)
180 		return hp_zx1_ioc_owner();
181 
182 	return hp_zx1_ioc_shared();
183 }
184 
185 static int
186 hp_zx1_lba_find_capability (volatile u8 __iomem *hpa, int cap)
187 {
188 	u16 status;
189 	u8 pos, id;
190 	int ttl = 48;
191 
192 	status = readw(hpa+PCI_STATUS);
193 	if (!(status & PCI_STATUS_CAP_LIST))
194 		return 0;
195 	pos = readb(hpa+PCI_CAPABILITY_LIST);
196 	while (ttl-- && pos >= 0x40) {
197 		pos &= ~3;
198 		id = readb(hpa+pos+PCI_CAP_LIST_ID);
199 		if (id == 0xff)
200 			break;
201 		if (id == cap)
202 			return pos;
203 		pos = readb(hpa+pos+PCI_CAP_LIST_NEXT);
204 	}
205 	return 0;
206 }
207 
208 static int __init
209 hp_zx1_lba_init (u64 hpa)
210 {
211 	struct _hp_private *hp = &hp_private;
212 	int cap;
213 
214 	hp->lba_regs = ioremap(hpa, 256);
215 	if (!hp->lba_regs)
216 		return -ENOMEM;
217 
218 	hp->lba_cap_offset = hp_zx1_lba_find_capability(hp->lba_regs, PCI_CAP_ID_AGP);
219 
220 	cap = readl(hp->lba_regs+hp->lba_cap_offset) & 0xff;
221 	if (cap != PCI_CAP_ID_AGP) {
222 		printk(KERN_ERR PFX "Invalid capability ID 0x%02x at 0x%x\n",
223 		       cap, hp->lba_cap_offset);
224 		return -ENODEV;
225 	}
226 
227 	return 0;
228 }
229 
230 static int
231 hp_zx1_fetch_size(void)
232 {
233 	int size;
234 
235 	size = hp_private.gart_size / MB(1);
236 	hp_zx1_sizes[0].size = size;
237 	agp_bridge->current_size = (void *) &hp_zx1_sizes[0];
238 	return size;
239 }
240 
241 static int
242 hp_zx1_configure (void)
243 {
244 	struct _hp_private *hp = &hp_private;
245 
246 	agp_bridge->gart_bus_addr = hp->gart_base;
247 	agp_bridge->capndx = hp->lba_cap_offset;
248 	agp_bridge->mode = readl(hp->lba_regs+hp->lba_cap_offset+PCI_AGP_STATUS);
249 
250 	if (hp->io_pdir_owner) {
251 		writel(virt_to_phys(hp->io_pdir), hp->ioc_regs+HP_ZX1_PDIR_BASE);
252 		readl(hp->ioc_regs+HP_ZX1_PDIR_BASE);
253 		writel(hp->io_tlb_ps, hp->ioc_regs+HP_ZX1_TCNFG);
254 		readl(hp->ioc_regs+HP_ZX1_TCNFG);
255 		writel(~(HP_ZX1_IOVA_SIZE-1), hp->ioc_regs+HP_ZX1_IMASK);
256 		readl(hp->ioc_regs+HP_ZX1_IMASK);
257 		writel(hp->iova_base|1, hp->ioc_regs+HP_ZX1_IBASE);
258 		readl(hp->ioc_regs+HP_ZX1_IBASE);
259 		writel(hp->iova_base|log2(HP_ZX1_IOVA_SIZE), hp->ioc_regs+HP_ZX1_PCOM);
260 		readl(hp->ioc_regs+HP_ZX1_PCOM);
261 	}
262 
263 	return 0;
264 }
265 
266 static void
267 hp_zx1_cleanup (void)
268 {
269 	struct _hp_private *hp = &hp_private;
270 
271 	if (hp->ioc_regs) {
272 		if (hp->io_pdir_owner) {
273 			writeq(0, hp->ioc_regs+HP_ZX1_IBASE);
274 			readq(hp->ioc_regs+HP_ZX1_IBASE);
275 		}
276 		iounmap(hp->ioc_regs);
277 	}
278 	if (hp->lba_regs)
279 		iounmap(hp->lba_regs);
280 }
281 
282 static void
283 hp_zx1_tlbflush (struct agp_memory *mem)
284 {
285 	struct _hp_private *hp = &hp_private;
286 
287 	writeq(hp->gart_base | log2(hp->gart_size), hp->ioc_regs+HP_ZX1_PCOM);
288 	readq(hp->ioc_regs+HP_ZX1_PCOM);
289 }
290 
291 static int
292 hp_zx1_create_gatt_table (struct agp_bridge_data *bridge)
293 {
294 	struct _hp_private *hp = &hp_private;
295 	int i;
296 
297 	if (hp->io_pdir_owner) {
298 		hp->io_pdir = (u64 *) __get_free_pages(GFP_KERNEL,
299 						get_order(hp->io_pdir_size));
300 		if (!hp->io_pdir) {
301 			printk(KERN_ERR PFX "Couldn't allocate contiguous "
302 				"memory for I/O PDIR\n");
303 			hp->gatt = NULL;
304 			hp->gatt_entries = 0;
305 			return -ENOMEM;
306 		}
307 		memset(hp->io_pdir, 0, hp->io_pdir_size);
308 
309 		hp->gatt = &hp->io_pdir[HP_ZX1_IOVA_TO_PDIR(hp->gart_base)];
310 	}
311 
312 	for (i = 0; i < hp->gatt_entries; i++) {
313 		hp->gatt[i] = (unsigned long) agp_bridge->scratch_page;
314 	}
315 
316 	return 0;
317 }
318 
319 static int
320 hp_zx1_free_gatt_table (struct agp_bridge_data *bridge)
321 {
322 	struct _hp_private *hp = &hp_private;
323 
324 	if (hp->io_pdir_owner)
325 		free_pages((unsigned long) hp->io_pdir,
326 			    get_order(hp->io_pdir_size));
327 	else
328 		hp->gatt[0] = HP_ZX1_SBA_IOMMU_COOKIE;
329 	return 0;
330 }
331 
332 static int
333 hp_zx1_insert_memory (struct agp_memory *mem, off_t pg_start, int type)
334 {
335 	struct _hp_private *hp = &hp_private;
336 	int i, k;
337 	off_t j, io_pg_start;
338 	int io_pg_count;
339 
340 	if (type != 0 || mem->type != 0) {
341 		return -EINVAL;
342 	}
343 
344 	io_pg_start = hp->io_pages_per_kpage * pg_start;
345 	io_pg_count = hp->io_pages_per_kpage * mem->page_count;
346 	if ((io_pg_start + io_pg_count) > hp->gatt_entries) {
347 		return -EINVAL;
348 	}
349 
350 	j = io_pg_start;
351 	while (j < (io_pg_start + io_pg_count)) {
352 		if (hp->gatt[j]) {
353 			return -EBUSY;
354 		}
355 		j++;
356 	}
357 
358 	if (mem->is_flushed == FALSE) {
359 		global_cache_flush();
360 		mem->is_flushed = TRUE;
361 	}
362 
363 	for (i = 0, j = io_pg_start; i < mem->page_count; i++) {
364 		unsigned long paddr;
365 
366 		paddr = mem->memory[i];
367 		for (k = 0;
368 		     k < hp->io_pages_per_kpage;
369 		     k++, j++, paddr += hp->io_page_size) {
370 			hp->gatt[j] =
371 				agp_bridge->driver->mask_memory(agp_bridge,
372 					paddr, type);
373 		}
374 	}
375 
376 	agp_bridge->driver->tlb_flush(mem);
377 	return 0;
378 }
379 
380 static int
381 hp_zx1_remove_memory (struct agp_memory *mem, off_t pg_start, int type)
382 {
383 	struct _hp_private *hp = &hp_private;
384 	int i, io_pg_start, io_pg_count;
385 
386 	if (type != 0 || mem->type != 0) {
387 		return -EINVAL;
388 	}
389 
390 	io_pg_start = hp->io_pages_per_kpage * pg_start;
391 	io_pg_count = hp->io_pages_per_kpage * mem->page_count;
392 	for (i = io_pg_start; i < io_pg_count + io_pg_start; i++) {
393 		hp->gatt[i] = agp_bridge->scratch_page;
394 	}
395 
396 	agp_bridge->driver->tlb_flush(mem);
397 	return 0;
398 }
399 
400 static unsigned long
401 hp_zx1_mask_memory (struct agp_bridge_data *bridge,
402 	unsigned long addr, int type)
403 {
404 	return HP_ZX1_PDIR_VALID_BIT | addr;
405 }
406 
407 static void
408 hp_zx1_enable (struct agp_bridge_data *bridge, u32 mode)
409 {
410 	struct _hp_private *hp = &hp_private;
411 	u32 command;
412 
413 	command = readl(hp->lba_regs+hp->lba_cap_offset+PCI_AGP_STATUS);
414 	command = agp_collect_device_status(bridge, mode, command);
415 	command |= 0x00000100;
416 
417 	writel(command, hp->lba_regs+hp->lba_cap_offset+PCI_AGP_COMMAND);
418 
419 	agp_device_command(command, (mode & AGP8X_MODE) != 0);
420 }
421 
422 struct agp_bridge_driver hp_zx1_driver = {
423 	.owner			= THIS_MODULE,
424 	.size_type		= FIXED_APER_SIZE,
425 	.configure		= hp_zx1_configure,
426 	.fetch_size		= hp_zx1_fetch_size,
427 	.cleanup		= hp_zx1_cleanup,
428 	.tlb_flush		= hp_zx1_tlbflush,
429 	.mask_memory		= hp_zx1_mask_memory,
430 	.masks			= hp_zx1_masks,
431 	.agp_enable		= hp_zx1_enable,
432 	.cache_flush		= global_cache_flush,
433 	.create_gatt_table	= hp_zx1_create_gatt_table,
434 	.free_gatt_table	= hp_zx1_free_gatt_table,
435 	.insert_memory		= hp_zx1_insert_memory,
436 	.remove_memory		= hp_zx1_remove_memory,
437 	.alloc_by_type		= agp_generic_alloc_by_type,
438 	.free_by_type		= agp_generic_free_by_type,
439 	.agp_alloc_page		= agp_generic_alloc_page,
440 	.agp_destroy_page	= agp_generic_destroy_page,
441 	.cant_use_aperture	= 1,
442 };
443 
444 static int __init
445 hp_zx1_setup (u64 ioc_hpa, u64 lba_hpa)
446 {
447 	struct agp_bridge_data *bridge;
448 	int error = 0;
449 
450 	error = hp_zx1_ioc_init(ioc_hpa);
451 	if (error)
452 		goto fail;
453 
454 	error = hp_zx1_lba_init(lba_hpa);
455 	if (error)
456 		goto fail;
457 
458 	bridge = agp_alloc_bridge();
459 	if (!bridge) {
460 		error = -ENOMEM;
461 		goto fail;
462 	}
463 	bridge->driver = &hp_zx1_driver;
464 
465 	fake_bridge_dev.vendor = PCI_VENDOR_ID_HP;
466 	fake_bridge_dev.device = PCI_DEVICE_ID_HP_PCIX_LBA;
467 	bridge->dev = &fake_bridge_dev;
468 
469 	error = agp_add_bridge(bridge);
470   fail:
471 	if (error)
472 		hp_zx1_cleanup();
473 	return error;
474 }
475 
476 static acpi_status __init
477 zx1_gart_probe (acpi_handle obj, u32 depth, void *context, void **ret)
478 {
479 	acpi_handle handle, parent;
480 	acpi_status status;
481 	struct acpi_buffer buffer;
482 	struct acpi_device_info *info;
483 	u64 lba_hpa, sba_hpa, length;
484 	int match;
485 
486 	status = hp_acpi_csr_space(obj, &lba_hpa, &length);
487 	if (ACPI_FAILURE(status))
488 		return AE_OK; /* keep looking for another bridge */
489 
490 	/* Look for an enclosing IOC scope and find its CSR space */
491 	handle = obj;
492 	do {
493 		buffer.length = ACPI_ALLOCATE_LOCAL_BUFFER;
494 		status = acpi_get_object_info(handle, &buffer);
495 		if (ACPI_SUCCESS(status)) {
496 			/* TBD check _CID also */
497 			info = buffer.pointer;
498 			info->hardware_id.value[sizeof(info->hardware_id)-1] = '\0';
499 			match = (strcmp(info->hardware_id.value, "HWP0001") == 0);
500 			ACPI_MEM_FREE(info);
501 			if (match) {
502 				status = hp_acpi_csr_space(handle, &sba_hpa, &length);
503 				if (ACPI_SUCCESS(status))
504 					break;
505 				else {
506 					printk(KERN_ERR PFX "Detected HP ZX1 "
507 					       "AGP LBA but no IOC.\n");
508 					return AE_OK;
509 				}
510 			}
511 		}
512 
513 		status = acpi_get_parent(handle, &parent);
514 		handle = parent;
515 	} while (ACPI_SUCCESS(status));
516 
517 	if (hp_zx1_setup(sba_hpa + HP_ZX1_IOC_OFFSET, lba_hpa))
518 		return AE_OK;
519 
520 	printk(KERN_INFO PFX "Detected HP ZX1 %s AGP chipset (ioc=%lx, lba=%lx)\n",
521 		(char *) context, sba_hpa + HP_ZX1_IOC_OFFSET, lba_hpa);
522 
523 	hp_zx1_gart_found = 1;
524 	return AE_CTRL_TERMINATE; /* we only support one bridge; quit looking */
525 }
526 
527 static int __init
528 agp_hp_init (void)
529 {
530 	if (agp_off)
531 		return -EINVAL;
532 
533 	acpi_get_devices("HWP0003", zx1_gart_probe, "HWP0003", NULL);
534 	if (hp_zx1_gart_found)
535 		return 0;
536 
537 	acpi_get_devices("HWP0007", zx1_gart_probe, "HWP0007", NULL);
538 	if (hp_zx1_gart_found)
539 		return 0;
540 
541 	return -ENODEV;
542 }
543 
544 static void __exit
545 agp_hp_cleanup (void)
546 {
547 }
548 
549 module_init(agp_hp_init);
550 module_exit(agp_hp_cleanup);
551 
552 MODULE_LICENSE("GPL and additional rights");
553