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