xref: /openbmc/linux/drivers/char/agp/hp-agp.c (revision 8fa5723aa7e053d498336b48448b292fc2e0458b)
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 #include <linux/log2.h>
18 
19 #include <asm/acpi-ext.h>
20 
21 #include "agp.h"
22 
23 #define HP_ZX1_IOC_OFFSET	0x1000  /* ACPI reports SBA, we want IOC */
24 
25 /* HP ZX1 IOC registers */
26 #define HP_ZX1_IBASE		0x300
27 #define HP_ZX1_IMASK		0x308
28 #define HP_ZX1_PCOM		0x310
29 #define HP_ZX1_TCNFG		0x318
30 #define HP_ZX1_PDIR_BASE	0x320
31 
32 #define HP_ZX1_IOVA_BASE	GB(1UL)
33 #define HP_ZX1_IOVA_SIZE	GB(1UL)
34 #define HP_ZX1_GART_SIZE	(HP_ZX1_IOVA_SIZE / 2)
35 #define HP_ZX1_SBA_IOMMU_COOKIE	0x0000badbadc0ffeeUL
36 
37 #define HP_ZX1_PDIR_VALID_BIT	0x8000000000000000UL
38 #define HP_ZX1_IOVA_TO_PDIR(va)	((va - hp_private.iova_base) >> hp_private.io_tlb_shift)
39 
40 #define AGP8X_MODE_BIT		3
41 #define AGP8X_MODE		(1 << AGP8X_MODE_BIT)
42 
43 /* AGP bridge need not be PCI device, but DRM thinks it is. */
44 static struct pci_dev fake_bridge_dev;
45 
46 static int hp_zx1_gart_found;
47 
48 static struct aper_size_info_fixed hp_zx1_sizes[] =
49 {
50 	{0, 0, 0},		/* filled in by hp_zx1_fetch_size() */
51 };
52 
53 static struct gatt_mask hp_zx1_masks[] =
54 {
55 	{.mask = HP_ZX1_PDIR_VALID_BIT, .type = 0}
56 };
57 
58 static struct _hp_private {
59 	volatile u8 __iomem *ioc_regs;
60 	volatile u8 __iomem *lba_regs;
61 	int lba_cap_offset;
62 	u64 *io_pdir;		// PDIR for entire IOVA
63 	u64 *gatt;		// PDIR just for GART (subset of above)
64 	u64 gatt_entries;
65 	u64 iova_base;
66 	u64 gart_base;
67 	u64 gart_size;
68 	u64 io_pdir_size;
69 	int io_pdir_owner;	// do we own it, or share it with sba_iommu?
70 	int io_page_size;
71 	int io_tlb_shift;
72 	int io_tlb_ps;		// IOC ps config
73 	int io_pages_per_kpage;
74 } hp_private;
75 
76 static int __init hp_zx1_ioc_shared(void)
77 {
78 	struct _hp_private *hp = &hp_private;
79 
80 	printk(KERN_INFO PFX "HP ZX1 IOC: IOPDIR shared with sba_iommu\n");
81 
82 	/*
83 	 * IOC already configured by sba_iommu module; just use
84 	 * its setup.  We assume:
85 	 *	- IOVA space is 1Gb in size
86 	 *	- first 512Mb is IOMMU, second 512Mb is GART
87 	 */
88 	hp->io_tlb_ps = readq(hp->ioc_regs+HP_ZX1_TCNFG);
89 	switch (hp->io_tlb_ps) {
90 		case 0: hp->io_tlb_shift = 12; break;
91 		case 1: hp->io_tlb_shift = 13; break;
92 		case 2: hp->io_tlb_shift = 14; break;
93 		case 3: hp->io_tlb_shift = 16; break;
94 		default:
95 			printk(KERN_ERR PFX "Invalid IOTLB page size "
96 			       "configuration 0x%x\n", hp->io_tlb_ps);
97 			hp->gatt = NULL;
98 			hp->gatt_entries = 0;
99 			return -ENODEV;
100 	}
101 	hp->io_page_size = 1 << hp->io_tlb_shift;
102 	hp->io_pages_per_kpage = PAGE_SIZE / hp->io_page_size;
103 
104 	hp->iova_base = readq(hp->ioc_regs+HP_ZX1_IBASE) & ~0x1;
105 	hp->gart_base = hp->iova_base + HP_ZX1_IOVA_SIZE - HP_ZX1_GART_SIZE;
106 
107 	hp->gart_size = HP_ZX1_GART_SIZE;
108 	hp->gatt_entries = hp->gart_size / hp->io_page_size;
109 
110 	hp->io_pdir = gart_to_virt(readq(hp->ioc_regs+HP_ZX1_PDIR_BASE));
111 	hp->gatt = &hp->io_pdir[HP_ZX1_IOVA_TO_PDIR(hp->gart_base)];
112 
113 	if (hp->gatt[0] != HP_ZX1_SBA_IOMMU_COOKIE) {
114 		/* Normal case when no AGP device in system */
115 		hp->gatt = NULL;
116 		hp->gatt_entries = 0;
117 		printk(KERN_ERR PFX "No reserved IO PDIR entry found; "
118 		       "GART disabled\n");
119 		return -ENODEV;
120 	}
121 
122 	return 0;
123 }
124 
125 static int __init
126 hp_zx1_ioc_owner (void)
127 {
128 	struct _hp_private *hp = &hp_private;
129 
130 	printk(KERN_INFO PFX "HP ZX1 IOC: IOPDIR dedicated to GART\n");
131 
132 	/*
133 	 * Select an IOV page size no larger than system page size.
134 	 */
135 	if (PAGE_SIZE >= KB(64)) {
136 		hp->io_tlb_shift = 16;
137 		hp->io_tlb_ps = 3;
138 	} else if (PAGE_SIZE >= KB(16)) {
139 		hp->io_tlb_shift = 14;
140 		hp->io_tlb_ps = 2;
141 	} else if (PAGE_SIZE >= KB(8)) {
142 		hp->io_tlb_shift = 13;
143 		hp->io_tlb_ps = 1;
144 	} else {
145 		hp->io_tlb_shift = 12;
146 		hp->io_tlb_ps = 0;
147 	}
148 	hp->io_page_size = 1 << hp->io_tlb_shift;
149 	hp->io_pages_per_kpage = PAGE_SIZE / hp->io_page_size;
150 
151 	hp->iova_base = HP_ZX1_IOVA_BASE;
152 	hp->gart_size = HP_ZX1_GART_SIZE;
153 	hp->gart_base = hp->iova_base + HP_ZX1_IOVA_SIZE - hp->gart_size;
154 
155 	hp->gatt_entries = hp->gart_size / hp->io_page_size;
156 	hp->io_pdir_size = (HP_ZX1_IOVA_SIZE / hp->io_page_size) * sizeof(u64);
157 
158 	return 0;
159 }
160 
161 static int __init
162 hp_zx1_ioc_init (u64 hpa)
163 {
164 	struct _hp_private *hp = &hp_private;
165 
166 	hp->ioc_regs = ioremap(hpa, 1024);
167 	if (!hp->ioc_regs)
168 		return -ENOMEM;
169 
170 	/*
171 	 * If the IOTLB is currently disabled, we can take it over.
172 	 * Otherwise, we have to share with sba_iommu.
173 	 */
174 	hp->io_pdir_owner = (readq(hp->ioc_regs+HP_ZX1_IBASE) & 0x1) == 0;
175 
176 	if (hp->io_pdir_owner)
177 		return hp_zx1_ioc_owner();
178 
179 	return hp_zx1_ioc_shared();
180 }
181 
182 static int
183 hp_zx1_lba_find_capability (volatile u8 __iomem *hpa, int cap)
184 {
185 	u16 status;
186 	u8 pos, id;
187 	int ttl = 48;
188 
189 	status = readw(hpa+PCI_STATUS);
190 	if (!(status & PCI_STATUS_CAP_LIST))
191 		return 0;
192 	pos = readb(hpa+PCI_CAPABILITY_LIST);
193 	while (ttl-- && pos >= 0x40) {
194 		pos &= ~3;
195 		id = readb(hpa+pos+PCI_CAP_LIST_ID);
196 		if (id == 0xff)
197 			break;
198 		if (id == cap)
199 			return pos;
200 		pos = readb(hpa+pos+PCI_CAP_LIST_NEXT);
201 	}
202 	return 0;
203 }
204 
205 static int __init
206 hp_zx1_lba_init (u64 hpa)
207 {
208 	struct _hp_private *hp = &hp_private;
209 	int cap;
210 
211 	hp->lba_regs = ioremap(hpa, 256);
212 	if (!hp->lba_regs)
213 		return -ENOMEM;
214 
215 	hp->lba_cap_offset = hp_zx1_lba_find_capability(hp->lba_regs, PCI_CAP_ID_AGP);
216 
217 	cap = readl(hp->lba_regs+hp->lba_cap_offset) & 0xff;
218 	if (cap != PCI_CAP_ID_AGP) {
219 		printk(KERN_ERR PFX "Invalid capability ID 0x%02x at 0x%x\n",
220 		       cap, hp->lba_cap_offset);
221 		iounmap(hp->lba_regs);
222 		return -ENODEV;
223 	}
224 
225 	return 0;
226 }
227 
228 static int
229 hp_zx1_fetch_size(void)
230 {
231 	int size;
232 
233 	size = hp_private.gart_size / MB(1);
234 	hp_zx1_sizes[0].size = size;
235 	agp_bridge->current_size = (void *) &hp_zx1_sizes[0];
236 	return size;
237 }
238 
239 static int
240 hp_zx1_configure (void)
241 {
242 	struct _hp_private *hp = &hp_private;
243 
244 	agp_bridge->gart_bus_addr = hp->gart_base;
245 	agp_bridge->capndx = hp->lba_cap_offset;
246 	agp_bridge->mode = readl(hp->lba_regs+hp->lba_cap_offset+PCI_AGP_STATUS);
247 
248 	if (hp->io_pdir_owner) {
249 		writel(virt_to_gart(hp->io_pdir), hp->ioc_regs+HP_ZX1_PDIR_BASE);
250 		readl(hp->ioc_regs+HP_ZX1_PDIR_BASE);
251 		writel(hp->io_tlb_ps, hp->ioc_regs+HP_ZX1_TCNFG);
252 		readl(hp->ioc_regs+HP_ZX1_TCNFG);
253 		writel((unsigned int)(~(HP_ZX1_IOVA_SIZE-1)), hp->ioc_regs+HP_ZX1_IMASK);
254 		readl(hp->ioc_regs+HP_ZX1_IMASK);
255 		writel(hp->iova_base|1, hp->ioc_regs+HP_ZX1_IBASE);
256 		readl(hp->ioc_regs+HP_ZX1_IBASE);
257 		writel(hp->iova_base|ilog2(HP_ZX1_IOVA_SIZE), hp->ioc_regs+HP_ZX1_PCOM);
258 		readl(hp->ioc_regs+HP_ZX1_PCOM);
259 	}
260 
261 	return 0;
262 }
263 
264 static void
265 hp_zx1_cleanup (void)
266 {
267 	struct _hp_private *hp = &hp_private;
268 
269 	if (hp->ioc_regs) {
270 		if (hp->io_pdir_owner) {
271 			writeq(0, hp->ioc_regs+HP_ZX1_IBASE);
272 			readq(hp->ioc_regs+HP_ZX1_IBASE);
273 		}
274 		iounmap(hp->ioc_regs);
275 	}
276 	if (hp->lba_regs)
277 		iounmap(hp->lba_regs);
278 }
279 
280 static void
281 hp_zx1_tlbflush (struct agp_memory *mem)
282 {
283 	struct _hp_private *hp = &hp_private;
284 
285 	writeq(hp->gart_base | ilog2(hp->gart_size), hp->ioc_regs+HP_ZX1_PCOM);
286 	readq(hp->ioc_regs+HP_ZX1_PCOM);
287 }
288 
289 static int
290 hp_zx1_create_gatt_table (struct agp_bridge_data *bridge)
291 {
292 	struct _hp_private *hp = &hp_private;
293 	int i;
294 
295 	if (hp->io_pdir_owner) {
296 		hp->io_pdir = (u64 *) __get_free_pages(GFP_KERNEL,
297 						get_order(hp->io_pdir_size));
298 		if (!hp->io_pdir) {
299 			printk(KERN_ERR PFX "Couldn't allocate contiguous "
300 				"memory for I/O PDIR\n");
301 			hp->gatt = NULL;
302 			hp->gatt_entries = 0;
303 			return -ENOMEM;
304 		}
305 		memset(hp->io_pdir, 0, hp->io_pdir_size);
306 
307 		hp->gatt = &hp->io_pdir[HP_ZX1_IOVA_TO_PDIR(hp->gart_base)];
308 	}
309 
310 	for (i = 0; i < hp->gatt_entries; i++) {
311 		hp->gatt[i] = (unsigned long) agp_bridge->scratch_page;
312 	}
313 
314 	return 0;
315 }
316 
317 static int
318 hp_zx1_free_gatt_table (struct agp_bridge_data *bridge)
319 {
320 	struct _hp_private *hp = &hp_private;
321 
322 	if (hp->io_pdir_owner)
323 		free_pages((unsigned long) hp->io_pdir,
324 			    get_order(hp->io_pdir_size));
325 	else
326 		hp->gatt[0] = HP_ZX1_SBA_IOMMU_COOKIE;
327 	return 0;
328 }
329 
330 static int
331 hp_zx1_insert_memory (struct agp_memory *mem, off_t pg_start, int type)
332 {
333 	struct _hp_private *hp = &hp_private;
334 	int i, k;
335 	off_t j, io_pg_start;
336 	int io_pg_count;
337 
338 	if (type != 0 || mem->type != 0) {
339 		return -EINVAL;
340 	}
341 
342 	io_pg_start = hp->io_pages_per_kpage * pg_start;
343 	io_pg_count = hp->io_pages_per_kpage * mem->page_count;
344 	if ((io_pg_start + io_pg_count) > hp->gatt_entries) {
345 		return -EINVAL;
346 	}
347 
348 	j = io_pg_start;
349 	while (j < (io_pg_start + io_pg_count)) {
350 		if (hp->gatt[j]) {
351 			return -EBUSY;
352 		}
353 		j++;
354 	}
355 
356 	if (!mem->is_flushed) {
357 		global_cache_flush();
358 		mem->is_flushed = true;
359 	}
360 
361 	for (i = 0, j = io_pg_start; i < mem->page_count; i++) {
362 		unsigned long paddr;
363 
364 		paddr = mem->memory[i];
365 		for (k = 0;
366 		     k < hp->io_pages_per_kpage;
367 		     k++, j++, paddr += hp->io_page_size) {
368 			hp->gatt[j] =
369 				agp_bridge->driver->mask_memory(agp_bridge,
370 					paddr, type);
371 		}
372 	}
373 
374 	agp_bridge->driver->tlb_flush(mem);
375 	return 0;
376 }
377 
378 static int
379 hp_zx1_remove_memory (struct agp_memory *mem, off_t pg_start, int type)
380 {
381 	struct _hp_private *hp = &hp_private;
382 	int i, io_pg_start, io_pg_count;
383 
384 	if (type != 0 || mem->type != 0) {
385 		return -EINVAL;
386 	}
387 
388 	io_pg_start = hp->io_pages_per_kpage * pg_start;
389 	io_pg_count = hp->io_pages_per_kpage * mem->page_count;
390 	for (i = io_pg_start; i < io_pg_count + io_pg_start; i++) {
391 		hp->gatt[i] = agp_bridge->scratch_page;
392 	}
393 
394 	agp_bridge->driver->tlb_flush(mem);
395 	return 0;
396 }
397 
398 static unsigned long
399 hp_zx1_mask_memory (struct agp_bridge_data *bridge,
400 	unsigned long addr, int type)
401 {
402 	return HP_ZX1_PDIR_VALID_BIT | addr;
403 }
404 
405 static void
406 hp_zx1_enable (struct agp_bridge_data *bridge, u32 mode)
407 {
408 	struct _hp_private *hp = &hp_private;
409 	u32 command;
410 
411 	command = readl(hp->lba_regs+hp->lba_cap_offset+PCI_AGP_STATUS);
412 	command = agp_collect_device_status(bridge, mode, command);
413 	command |= 0x00000100;
414 
415 	writel(command, hp->lba_regs+hp->lba_cap_offset+PCI_AGP_COMMAND);
416 
417 	agp_device_command(command, (mode & AGP8X_MODE) != 0);
418 }
419 
420 const struct agp_bridge_driver hp_zx1_driver = {
421 	.owner			= THIS_MODULE,
422 	.size_type		= FIXED_APER_SIZE,
423 	.configure		= hp_zx1_configure,
424 	.fetch_size		= hp_zx1_fetch_size,
425 	.cleanup		= hp_zx1_cleanup,
426 	.tlb_flush		= hp_zx1_tlbflush,
427 	.mask_memory		= hp_zx1_mask_memory,
428 	.masks			= hp_zx1_masks,
429 	.agp_enable		= hp_zx1_enable,
430 	.cache_flush		= global_cache_flush,
431 	.create_gatt_table	= hp_zx1_create_gatt_table,
432 	.free_gatt_table	= hp_zx1_free_gatt_table,
433 	.insert_memory		= hp_zx1_insert_memory,
434 	.remove_memory		= hp_zx1_remove_memory,
435 	.alloc_by_type		= agp_generic_alloc_by_type,
436 	.free_by_type		= agp_generic_free_by_type,
437 	.agp_alloc_page		= agp_generic_alloc_page,
438 	.agp_alloc_pages	= agp_generic_alloc_pages,
439 	.agp_destroy_page	= agp_generic_destroy_page,
440 	.agp_destroy_pages	= agp_generic_destroy_pages,
441 	.agp_type_to_mask_type  = agp_generic_type_to_mask_type,
442 	.cant_use_aperture	= true,
443 };
444 
445 static int __init
446 hp_zx1_setup (u64 ioc_hpa, u64 lba_hpa)
447 {
448 	struct agp_bridge_data *bridge;
449 	int error = 0;
450 
451 	error = hp_zx1_ioc_init(ioc_hpa);
452 	if (error)
453 		goto fail;
454 
455 	error = hp_zx1_lba_init(lba_hpa);
456 	if (error)
457 		goto fail;
458 
459 	bridge = agp_alloc_bridge();
460 	if (!bridge) {
461 		error = -ENOMEM;
462 		goto fail;
463 	}
464 	bridge->driver = &hp_zx1_driver;
465 
466 	fake_bridge_dev.vendor = PCI_VENDOR_ID_HP;
467 	fake_bridge_dev.device = PCI_DEVICE_ID_HP_PCIX_LBA;
468 	bridge->dev = &fake_bridge_dev;
469 
470 	error = agp_add_bridge(bridge);
471   fail:
472 	if (error)
473 		hp_zx1_cleanup();
474 	return error;
475 }
476 
477 static acpi_status __init
478 zx1_gart_probe (acpi_handle obj, u32 depth, void *context, void **ret)
479 {
480 	acpi_handle handle, parent;
481 	acpi_status status;
482 	struct acpi_buffer buffer;
483 	struct acpi_device_info *info;
484 	u64 lba_hpa, sba_hpa, length;
485 	int match;
486 
487 	status = hp_acpi_csr_space(obj, &lba_hpa, &length);
488 	if (ACPI_FAILURE(status))
489 		return AE_OK; /* keep looking for another bridge */
490 
491 	/* Look for an enclosing IOC scope and find its CSR space */
492 	handle = obj;
493 	do {
494 		buffer.length = ACPI_ALLOCATE_LOCAL_BUFFER;
495 		status = acpi_get_object_info(handle, &buffer);
496 		if (ACPI_SUCCESS(status)) {
497 			/* TBD check _CID also */
498 			info = buffer.pointer;
499 			info->hardware_id.value[sizeof(info->hardware_id)-1] = '\0';
500 			match = (strcmp(info->hardware_id.value, "HWP0001") == 0);
501 			kfree(info);
502 			if (match) {
503 				status = hp_acpi_csr_space(handle, &sba_hpa, &length);
504 				if (ACPI_SUCCESS(status))
505 					break;
506 				else {
507 					printk(KERN_ERR PFX "Detected HP ZX1 "
508 					       "AGP LBA but no IOC.\n");
509 					return AE_OK;
510 				}
511 			}
512 		}
513 
514 		status = acpi_get_parent(handle, &parent);
515 		handle = parent;
516 	} while (ACPI_SUCCESS(status));
517 
518 	if (hp_zx1_setup(sba_hpa + HP_ZX1_IOC_OFFSET, lba_hpa))
519 		return AE_OK;
520 
521 	printk(KERN_INFO PFX "Detected HP ZX1 %s AGP chipset (ioc=%lx, lba=%lx)\n",
522 		(char *) context, sba_hpa + HP_ZX1_IOC_OFFSET, lba_hpa);
523 
524 	hp_zx1_gart_found = 1;
525 	return AE_CTRL_TERMINATE; /* we only support one bridge; quit looking */
526 }
527 
528 static int __init
529 agp_hp_init (void)
530 {
531 	if (agp_off)
532 		return -EINVAL;
533 
534 	acpi_get_devices("HWP0003", zx1_gart_probe, "HWP0003", NULL);
535 	if (hp_zx1_gart_found)
536 		return 0;
537 
538 	acpi_get_devices("HWP0007", zx1_gart_probe, "HWP0007", NULL);
539 	if (hp_zx1_gart_found)
540 		return 0;
541 
542 	return -ENODEV;
543 }
544 
545 static void __exit
546 agp_hp_cleanup (void)
547 {
548 }
549 
550 module_init(agp_hp_init);
551 module_exit(agp_hp_cleanup);
552 
553 MODULE_LICENSE("GPL and additional rights");
554