xref: /openbmc/linux/drivers/char/agp/hp-agp.c (revision d9fd5a71)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * HP zx1 AGPGART routines.
4  *
5  * (c) Copyright 2002, 2003 Hewlett-Packard Development Company, L.P.
6  *	Bjorn Helgaas <bjorn.helgaas@hp.com>
7  */
8 
9 #include <linux/acpi.h>
10 #include <linux/module.h>
11 #include <linux/pci.h>
12 #include <linux/init.h>
13 #include <linux/agp_backend.h>
14 #include <linux/log2.h>
15 #include <linux/slab.h>
16 
17 #include <asm/acpi-ext.h>
18 
19 #include "agp.h"
20 
21 #define HP_ZX1_IOC_OFFSET	0x1000  /* ACPI reports SBA, we want IOC */
22 
23 /* HP ZX1 IOC registers */
24 #define HP_ZX1_IBASE		0x300
25 #define HP_ZX1_IMASK		0x308
26 #define HP_ZX1_PCOM		0x310
27 #define HP_ZX1_TCNFG		0x318
28 #define HP_ZX1_PDIR_BASE	0x320
29 
30 #define HP_ZX1_IOVA_BASE	GB(1UL)
31 #define HP_ZX1_IOVA_SIZE	GB(1UL)
32 #define HP_ZX1_GART_SIZE	(HP_ZX1_IOVA_SIZE / 2)
33 #define HP_ZX1_SBA_IOMMU_COOKIE	0x0000badbadc0ffeeUL
34 
35 #define HP_ZX1_PDIR_VALID_BIT	0x8000000000000000UL
36 #define HP_ZX1_IOVA_TO_PDIR(va)	((va - hp_private.iova_base) >> hp_private.io_tlb_shift)
37 
38 #define AGP8X_MODE_BIT		3
39 #define AGP8X_MODE		(1 << AGP8X_MODE_BIT)
40 
41 /* AGP bridge need not be PCI device, but DRM thinks it is. */
42 static struct pci_dev fake_bridge_dev;
43 
44 static int hp_zx1_gart_found;
45 
46 static struct aper_size_info_fixed hp_zx1_sizes[] =
47 {
48 	{0, 0, 0},		/* filled in by hp_zx1_fetch_size() */
49 };
50 
51 static struct gatt_mask hp_zx1_masks[] =
52 {
53 	{.mask = HP_ZX1_PDIR_VALID_BIT, .type = 0}
54 };
55 
56 static struct _hp_private {
57 	volatile u8 __iomem *ioc_regs;
58 	volatile u8 __iomem *lba_regs;
59 	int lba_cap_offset;
60 	u64 *io_pdir;		// PDIR for entire IOVA
61 	u64 *gatt;		// PDIR just for GART (subset of above)
62 	u64 gatt_entries;
63 	u64 iova_base;
64 	u64 gart_base;
65 	u64 gart_size;
66 	u64 io_pdir_size;
67 	int io_pdir_owner;	// do we own it, or share it with sba_iommu?
68 	int io_page_size;
69 	int io_tlb_shift;
70 	int io_tlb_ps;		// IOC ps config
71 	int io_pages_per_kpage;
72 } hp_private;
73 
74 static int __init hp_zx1_ioc_shared(void)
75 {
76 	struct _hp_private *hp = &hp_private;
77 
78 	printk(KERN_INFO PFX "HP ZX1 IOC: IOPDIR shared with sba_iommu\n");
79 
80 	/*
81 	 * IOC already configured by sba_iommu module; just use
82 	 * its setup.  We assume:
83 	 *	- IOVA space is 1Gb in size
84 	 *	- first 512Mb is IOMMU, second 512Mb is GART
85 	 */
86 	hp->io_tlb_ps = readq(hp->ioc_regs+HP_ZX1_TCNFG);
87 	switch (hp->io_tlb_ps) {
88 		case 0: hp->io_tlb_shift = 12; break;
89 		case 1: hp->io_tlb_shift = 13; break;
90 		case 2: hp->io_tlb_shift = 14; break;
91 		case 3: hp->io_tlb_shift = 16; break;
92 		default:
93 			printk(KERN_ERR PFX "Invalid IOTLB page size "
94 			       "configuration 0x%x\n", hp->io_tlb_ps);
95 			hp->gatt = NULL;
96 			hp->gatt_entries = 0;
97 			return -ENODEV;
98 	}
99 	hp->io_page_size = 1 << hp->io_tlb_shift;
100 	hp->io_pages_per_kpage = PAGE_SIZE / hp->io_page_size;
101 
102 	hp->iova_base = readq(hp->ioc_regs+HP_ZX1_IBASE) & ~0x1;
103 	hp->gart_base = hp->iova_base + HP_ZX1_IOVA_SIZE - HP_ZX1_GART_SIZE;
104 
105 	hp->gart_size = HP_ZX1_GART_SIZE;
106 	hp->gatt_entries = hp->gart_size / hp->io_page_size;
107 
108 	hp->io_pdir = phys_to_virt(readq(hp->ioc_regs+HP_ZX1_PDIR_BASE));
109 	hp->gatt = &hp->io_pdir[HP_ZX1_IOVA_TO_PDIR(hp->gart_base)];
110 
111 	if (hp->gatt[0] != HP_ZX1_SBA_IOMMU_COOKIE) {
112 		/* Normal case when no AGP device in system */
113 		hp->gatt = NULL;
114 		hp->gatt_entries = 0;
115 		printk(KERN_ERR PFX "No reserved IO PDIR entry found; "
116 		       "GART disabled\n");
117 		return -ENODEV;
118 	}
119 
120 	return 0;
121 }
122 
123 static int __init
124 hp_zx1_ioc_owner (void)
125 {
126 	struct _hp_private *hp = &hp_private;
127 
128 	printk(KERN_INFO PFX "HP ZX1 IOC: IOPDIR dedicated to GART\n");
129 
130 	/*
131 	 * Select an IOV page size no larger than system page size.
132 	 */
133 	if (PAGE_SIZE >= KB(64)) {
134 		hp->io_tlb_shift = 16;
135 		hp->io_tlb_ps = 3;
136 	} else if (PAGE_SIZE >= KB(16)) {
137 		hp->io_tlb_shift = 14;
138 		hp->io_tlb_ps = 2;
139 	} else if (PAGE_SIZE >= KB(8)) {
140 		hp->io_tlb_shift = 13;
141 		hp->io_tlb_ps = 1;
142 	} else {
143 		hp->io_tlb_shift = 12;
144 		hp->io_tlb_ps = 0;
145 	}
146 	hp->io_page_size = 1 << hp->io_tlb_shift;
147 	hp->io_pages_per_kpage = PAGE_SIZE / hp->io_page_size;
148 
149 	hp->iova_base = HP_ZX1_IOVA_BASE;
150 	hp->gart_size = HP_ZX1_GART_SIZE;
151 	hp->gart_base = hp->iova_base + HP_ZX1_IOVA_SIZE - hp->gart_size;
152 
153 	hp->gatt_entries = hp->gart_size / hp->io_page_size;
154 	hp->io_pdir_size = (HP_ZX1_IOVA_SIZE / hp->io_page_size) * sizeof(u64);
155 
156 	return 0;
157 }
158 
159 static int __init
160 hp_zx1_ioc_init (u64 hpa)
161 {
162 	struct _hp_private *hp = &hp_private;
163 
164 	hp->ioc_regs = ioremap(hpa, 1024);
165 	if (!hp->ioc_regs)
166 		return -ENOMEM;
167 
168 	/*
169 	 * If the IOTLB is currently disabled, we can take it over.
170 	 * Otherwise, we have to share with sba_iommu.
171 	 */
172 	hp->io_pdir_owner = (readq(hp->ioc_regs+HP_ZX1_IBASE) & 0x1) == 0;
173 
174 	if (hp->io_pdir_owner)
175 		return hp_zx1_ioc_owner();
176 
177 	return hp_zx1_ioc_shared();
178 }
179 
180 static int
181 hp_zx1_lba_find_capability (volatile u8 __iomem *hpa, int cap)
182 {
183 	u16 status;
184 	u8 pos, id;
185 	int ttl = 48;
186 
187 	status = readw(hpa+PCI_STATUS);
188 	if (!(status & PCI_STATUS_CAP_LIST))
189 		return 0;
190 	pos = readb(hpa+PCI_CAPABILITY_LIST);
191 	while (ttl-- && pos >= 0x40) {
192 		pos &= ~3;
193 		id = readb(hpa+pos+PCI_CAP_LIST_ID);
194 		if (id == 0xff)
195 			break;
196 		if (id == cap)
197 			return pos;
198 		pos = readb(hpa+pos+PCI_CAP_LIST_NEXT);
199 	}
200 	return 0;
201 }
202 
203 static int __init
204 hp_zx1_lba_init (u64 hpa)
205 {
206 	struct _hp_private *hp = &hp_private;
207 	int cap;
208 
209 	hp->lba_regs = ioremap(hpa, 256);
210 	if (!hp->lba_regs)
211 		return -ENOMEM;
212 
213 	hp->lba_cap_offset = hp_zx1_lba_find_capability(hp->lba_regs, PCI_CAP_ID_AGP);
214 
215 	cap = readl(hp->lba_regs+hp->lba_cap_offset) & 0xff;
216 	if (cap != PCI_CAP_ID_AGP) {
217 		printk(KERN_ERR PFX "Invalid capability ID 0x%02x at 0x%x\n",
218 		       cap, hp->lba_cap_offset);
219 		iounmap(hp->lba_regs);
220 		return -ENODEV;
221 	}
222 
223 	return 0;
224 }
225 
226 static int
227 hp_zx1_fetch_size(void)
228 {
229 	int size;
230 
231 	size = hp_private.gart_size / MB(1);
232 	hp_zx1_sizes[0].size = size;
233 	agp_bridge->current_size = (void *) &hp_zx1_sizes[0];
234 	return size;
235 }
236 
237 static int
238 hp_zx1_configure (void)
239 {
240 	struct _hp_private *hp = &hp_private;
241 
242 	agp_bridge->gart_bus_addr = hp->gart_base;
243 	agp_bridge->capndx = hp->lba_cap_offset;
244 	agp_bridge->mode = readl(hp->lba_regs+hp->lba_cap_offset+PCI_AGP_STATUS);
245 
246 	if (hp->io_pdir_owner) {
247 		writel(virt_to_phys(hp->io_pdir), hp->ioc_regs+HP_ZX1_PDIR_BASE);
248 		readl(hp->ioc_regs+HP_ZX1_PDIR_BASE);
249 		writel(hp->io_tlb_ps, hp->ioc_regs+HP_ZX1_TCNFG);
250 		readl(hp->ioc_regs+HP_ZX1_TCNFG);
251 		writel((unsigned int)(~(HP_ZX1_IOVA_SIZE-1)), hp->ioc_regs+HP_ZX1_IMASK);
252 		readl(hp->ioc_regs+HP_ZX1_IMASK);
253 		writel(hp->iova_base|1, hp->ioc_regs+HP_ZX1_IBASE);
254 		readl(hp->ioc_regs+HP_ZX1_IBASE);
255 		writel(hp->iova_base|ilog2(HP_ZX1_IOVA_SIZE), hp->ioc_regs+HP_ZX1_PCOM);
256 		readl(hp->ioc_regs+HP_ZX1_PCOM);
257 	}
258 
259 	return 0;
260 }
261 
262 static void
263 hp_zx1_cleanup (void)
264 {
265 	struct _hp_private *hp = &hp_private;
266 
267 	if (hp->ioc_regs) {
268 		if (hp->io_pdir_owner) {
269 			writeq(0, hp->ioc_regs+HP_ZX1_IBASE);
270 			readq(hp->ioc_regs+HP_ZX1_IBASE);
271 		}
272 		iounmap(hp->ioc_regs);
273 	}
274 	if (hp->lba_regs)
275 		iounmap(hp->lba_regs);
276 }
277 
278 static void
279 hp_zx1_tlbflush (struct agp_memory *mem)
280 {
281 	struct _hp_private *hp = &hp_private;
282 
283 	writeq(hp->gart_base | ilog2(hp->gart_size), hp->ioc_regs+HP_ZX1_PCOM);
284 	readq(hp->ioc_regs+HP_ZX1_PCOM);
285 }
286 
287 static int
288 hp_zx1_create_gatt_table (struct agp_bridge_data *bridge)
289 {
290 	struct _hp_private *hp = &hp_private;
291 	int i;
292 
293 	if (hp->io_pdir_owner) {
294 		hp->io_pdir = (u64 *) __get_free_pages(GFP_KERNEL,
295 						get_order(hp->io_pdir_size));
296 		if (!hp->io_pdir) {
297 			printk(KERN_ERR PFX "Couldn't allocate contiguous "
298 				"memory for I/O PDIR\n");
299 			hp->gatt = NULL;
300 			hp->gatt_entries = 0;
301 			return -ENOMEM;
302 		}
303 		memset(hp->io_pdir, 0, hp->io_pdir_size);
304 
305 		hp->gatt = &hp->io_pdir[HP_ZX1_IOVA_TO_PDIR(hp->gart_base)];
306 	}
307 
308 	for (i = 0; i < hp->gatt_entries; i++) {
309 		hp->gatt[i] = (unsigned long) agp_bridge->scratch_page;
310 	}
311 
312 	return 0;
313 }
314 
315 static int
316 hp_zx1_free_gatt_table (struct agp_bridge_data *bridge)
317 {
318 	struct _hp_private *hp = &hp_private;
319 
320 	if (hp->io_pdir_owner)
321 		free_pages((unsigned long) hp->io_pdir,
322 			    get_order(hp->io_pdir_size));
323 	else
324 		hp->gatt[0] = HP_ZX1_SBA_IOMMU_COOKIE;
325 	return 0;
326 }
327 
328 static int
329 hp_zx1_insert_memory (struct agp_memory *mem, off_t pg_start, int type)
330 {
331 	struct _hp_private *hp = &hp_private;
332 	int i, k;
333 	off_t j, io_pg_start;
334 	int io_pg_count;
335 
336 	if (type != mem->type ||
337 		agp_bridge->driver->agp_type_to_mask_type(agp_bridge, type)) {
338 		return -EINVAL;
339 	}
340 
341 	io_pg_start = hp->io_pages_per_kpage * pg_start;
342 	io_pg_count = hp->io_pages_per_kpage * mem->page_count;
343 	if ((io_pg_start + io_pg_count) > hp->gatt_entries) {
344 		return -EINVAL;
345 	}
346 
347 	j = io_pg_start;
348 	while (j < (io_pg_start + io_pg_count)) {
349 		if (hp->gatt[j]) {
350 			return -EBUSY;
351 		}
352 		j++;
353 	}
354 
355 	if (!mem->is_flushed) {
356 		global_cache_flush();
357 		mem->is_flushed = true;
358 	}
359 
360 	for (i = 0, j = io_pg_start; i < mem->page_count; i++) {
361 		unsigned long paddr;
362 
363 		paddr = page_to_phys(mem->pages[i]);
364 		for (k = 0;
365 		     k < hp->io_pages_per_kpage;
366 		     k++, j++, paddr += hp->io_page_size) {
367 			hp->gatt[j] = HP_ZX1_PDIR_VALID_BIT | paddr;
368 		}
369 	}
370 
371 	agp_bridge->driver->tlb_flush(mem);
372 	return 0;
373 }
374 
375 static int
376 hp_zx1_remove_memory (struct agp_memory *mem, off_t pg_start, int type)
377 {
378 	struct _hp_private *hp = &hp_private;
379 	int i, io_pg_start, io_pg_count;
380 
381 	if (type != mem->type ||
382 		agp_bridge->driver->agp_type_to_mask_type(agp_bridge, type)) {
383 		return -EINVAL;
384 	}
385 
386 	io_pg_start = hp->io_pages_per_kpage * pg_start;
387 	io_pg_count = hp->io_pages_per_kpage * mem->page_count;
388 	for (i = io_pg_start; i < io_pg_count + io_pg_start; i++) {
389 		hp->gatt[i] = agp_bridge->scratch_page;
390 	}
391 
392 	agp_bridge->driver->tlb_flush(mem);
393 	return 0;
394 }
395 
396 static unsigned long
397 hp_zx1_mask_memory (struct agp_bridge_data *bridge, dma_addr_t addr, int type)
398 {
399 	return HP_ZX1_PDIR_VALID_BIT | addr;
400 }
401 
402 static void
403 hp_zx1_enable (struct agp_bridge_data *bridge, u32 mode)
404 {
405 	struct _hp_private *hp = &hp_private;
406 	u32 command;
407 
408 	command = readl(hp->lba_regs+hp->lba_cap_offset+PCI_AGP_STATUS);
409 	command = agp_collect_device_status(bridge, mode, command);
410 	command |= 0x00000100;
411 
412 	writel(command, hp->lba_regs+hp->lba_cap_offset+PCI_AGP_COMMAND);
413 
414 	agp_device_command(command, (mode & AGP8X_MODE) != 0);
415 }
416 
417 const struct agp_bridge_driver hp_zx1_driver = {
418 	.owner			= THIS_MODULE,
419 	.size_type		= FIXED_APER_SIZE,
420 	.configure		= hp_zx1_configure,
421 	.fetch_size		= hp_zx1_fetch_size,
422 	.cleanup		= hp_zx1_cleanup,
423 	.tlb_flush		= hp_zx1_tlbflush,
424 	.mask_memory		= hp_zx1_mask_memory,
425 	.masks			= hp_zx1_masks,
426 	.agp_enable		= hp_zx1_enable,
427 	.cache_flush		= global_cache_flush,
428 	.create_gatt_table	= hp_zx1_create_gatt_table,
429 	.free_gatt_table	= hp_zx1_free_gatt_table,
430 	.insert_memory		= hp_zx1_insert_memory,
431 	.remove_memory		= hp_zx1_remove_memory,
432 	.alloc_by_type		= agp_generic_alloc_by_type,
433 	.free_by_type		= agp_generic_free_by_type,
434 	.agp_alloc_page		= agp_generic_alloc_page,
435 	.agp_alloc_pages	= agp_generic_alloc_pages,
436 	.agp_destroy_page	= agp_generic_destroy_page,
437 	.agp_destroy_pages	= agp_generic_destroy_pages,
438 	.agp_type_to_mask_type  = agp_generic_type_to_mask_type,
439 	.cant_use_aperture	= true,
440 };
441 
442 static int __init
443 hp_zx1_setup (u64 ioc_hpa, u64 lba_hpa)
444 {
445 	struct agp_bridge_data *bridge;
446 	int error = 0;
447 
448 	error = hp_zx1_ioc_init(ioc_hpa);
449 	if (error)
450 		goto fail;
451 
452 	error = hp_zx1_lba_init(lba_hpa);
453 	if (error)
454 		goto fail;
455 
456 	bridge = agp_alloc_bridge();
457 	if (!bridge) {
458 		error = -ENOMEM;
459 		goto fail;
460 	}
461 	bridge->driver = &hp_zx1_driver;
462 
463 	fake_bridge_dev.vendor = PCI_VENDOR_ID_HP;
464 	fake_bridge_dev.device = PCI_DEVICE_ID_HP_PCIX_LBA;
465 	bridge->dev = &fake_bridge_dev;
466 
467 	error = agp_add_bridge(bridge);
468   fail:
469 	if (error)
470 		hp_zx1_cleanup();
471 	return error;
472 }
473 
474 static acpi_status __init
475 zx1_gart_probe (acpi_handle obj, u32 depth, void *context, void **ret)
476 {
477 	acpi_handle handle, parent;
478 	acpi_status status;
479 	struct acpi_device_info *info;
480 	u64 lba_hpa, sba_hpa, length;
481 	int match;
482 
483 	status = hp_acpi_csr_space(obj, &lba_hpa, &length);
484 	if (ACPI_FAILURE(status))
485 		return AE_OK; /* keep looking for another bridge */
486 
487 	/* Look for an enclosing IOC scope and find its CSR space */
488 	handle = obj;
489 	do {
490 		status = acpi_get_object_info(handle, &info);
491 		if (ACPI_SUCCESS(status) && (info->valid & ACPI_VALID_HID)) {
492 			/* TBD check _CID also */
493 			match = (strcmp(info->hardware_id.string, "HWP0001") == 0);
494 			kfree(info);
495 			if (match) {
496 				status = hp_acpi_csr_space(handle, &sba_hpa, &length);
497 				if (ACPI_SUCCESS(status))
498 					break;
499 				else {
500 					printk(KERN_ERR PFX "Detected HP ZX1 "
501 					       "AGP LBA but no IOC.\n");
502 					return AE_OK;
503 				}
504 			}
505 		}
506 
507 		status = acpi_get_parent(handle, &parent);
508 		handle = parent;
509 	} while (ACPI_SUCCESS(status));
510 
511 	if (ACPI_FAILURE(status))
512 		return AE_OK;	/* found no enclosing IOC */
513 
514 	if (hp_zx1_setup(sba_hpa + HP_ZX1_IOC_OFFSET, lba_hpa))
515 		return AE_OK;
516 
517 	printk(KERN_INFO PFX "Detected HP ZX1 %s AGP chipset "
518 		"(ioc=%llx, lba=%llx)\n", (char *)context,
519 		sba_hpa + HP_ZX1_IOC_OFFSET, lba_hpa);
520 
521 	hp_zx1_gart_found = 1;
522 	return AE_CTRL_TERMINATE; /* we only support one bridge; quit looking */
523 }
524 
525 static int __init
526 agp_hp_init (void)
527 {
528 	if (agp_off)
529 		return -EINVAL;
530 
531 	acpi_get_devices("HWP0003", zx1_gart_probe, "HWP0003", NULL);
532 	if (hp_zx1_gart_found)
533 		return 0;
534 
535 	acpi_get_devices("HWP0007", zx1_gart_probe, "HWP0007", NULL);
536 	if (hp_zx1_gart_found)
537 		return 0;
538 
539 	return -ENODEV;
540 }
541 
542 static void __exit
543 agp_hp_cleanup (void)
544 {
545 }
546 
547 module_init(agp_hp_init);
548 module_exit(agp_hp_cleanup);
549 
550 MODULE_LICENSE("GPL and additional rights");
551