summaryrefslogtreecommitdiff
path: root/shared-core/radeon_ms_properties.c
AgeCommit message (Expand)Author
2008-01-15radeon_ms: use radeon connector type insted of drmJerome Glisse
2008-01-15radeon_ms: cope with lastest drm modesetting changeJerome Glisse
2008-01-15radeon_ms: add rom parsing & adapt codeJerome Glisse
'#n42'>42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817
/*
 * Copyright (C) 2005-2006 Erik Waling
 * Copyright (C) 2006 Stephane Marchesin
 * Copyright (C) 2007-2008 Stuart Bennett
 * Copyright (C) 2008 Maarten Maathuis.
 * All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice (including the
 * next paragraph) shall be included in all copies or substantial
 * portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 * IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 */

#include <asm/byteorder.h>
#include "nouveau_bios.h"
#include "nouveau_drv.h"

/* returns true if it mismatches */
static bool nv_checksum(const uint8_t *data, unsigned int length)
{
	/* there's a few checksums in the BIOS, so here's a generic checking function */
	int i;
	uint8_t sum = 0;

	for (i = 0; i < length; i++)
		sum += data[i];

	if (sum)
		return true;

	return false;
}

static int nv_valid_bios(struct drm_device *dev, uint8_t *data)
{
	/* check for BIOS signature */
	if (!(data[0] == 0x55 && data[1] == 0xAA)) {
		DRM_ERROR("BIOS signature not found.\n");
		return 0;
	}

	if (nv_checksum(data, data[2] * 512)) {
		DRM_ERROR("BIOS checksum invalid.\n");
		return 1;
	}

	return 2;
}

static void nv_shadow_bios_rom(struct drm_device *dev, uint8_t *data)
{
	struct drm_nouveau_private *dev_priv = dev->dev_private;
	int i;

	/* enable access to rom */
	NV_WRITE(NV04_PBUS_PCI_NV_20, NV04_PBUS_PCI_NV_20_ROM_SHADOW_DISABLED);

	/* This is also valid for pre-NV50, it just happened to be the only define already present. */
	for (i=0; i < NV50_PROM__ESIZE; i++) {
		/* Appearantly needed for a 6600GT/6800LE bug. */
		data[i] = DRM_READ8(dev_priv->mmio, NV50_PROM + i);
		data[i] = DRM_READ8(dev_priv->mmio, NV50_PROM + i);
		data[i] = DRM_READ8(dev_priv->mmio, NV50_PROM + i);
		data[i] = DRM_READ8(dev_priv->mmio, NV50_PROM + i);
		data[i] = DRM_READ8(dev_priv->mmio, NV50_PROM + i);
	}

	/* disable access to rom */
	NV_WRITE(NV04_PBUS_PCI_NV_20, NV04_PBUS_PCI_NV_20_ROM_SHADOW_ENABLED);
}

static void nv_shadow_bios_ramin(struct drm_device *dev, uint8_t *data)
{
	struct drm_nouveau_private *dev_priv = dev->dev_private;
	uint32_t old_bar0_pramin = 0;
	int i;

	/* Move the bios copy to the start of ramin? */
	if (dev_priv->card_type >= NV_50) {
		uint32_t vbios_vram = (NV_READ(0x619f04) & ~0xff) << 8;

		if (!vbios_vram)
			vbios_vram = (NV_READ(0x1700) << 16) + 0xf0000;

		old_bar0_pramin = NV_READ(0x1700);
		NV_WRITE(0x1700, vbios_vram >> 16);
	}

	for (i=0; i < NV50_PROM__ESIZE; i++)
		data[i] = DRM_READ8(dev_priv->mmio, NV04_PRAMIN + i);

	if (dev_priv->card_type >= NV_50)
		NV_WRITE(0x1700, old_bar0_pramin);
}

static bool nv_shadow_bios(struct drm_device *dev, uint8_t *data)
{
	nv_shadow_bios_rom(dev, data);
	if (nv_valid_bios(dev, data) == 2)
		return true;

	nv_shadow_bios_ramin(dev, data);
	if (nv_valid_bios(dev, data))
		return true;

	return false;
}

struct bit_entry {
	uint8_t id[2];
	uint16_t length;
	uint16_t offset;
};

static int parse_bit_C_tbl_entry(struct drm_device *dev, struct bios *bios, struct bit_entry *bitentry)
{
	/* offset + 8  (16 bits): PLL limits table pointer
	 *
	 * There's more in here, but that's unknown.
	 */

	if (bitentry->length < 10) {
		DRM_ERROR( "Do not understand BIT C table\n");
		return 0;
	}

	bios->pll_limit_tbl_ptr = le16_to_cpu(*((uint16_t *)(&bios->data[bitentry->offset + 8])));

	return 1;
}

static void parse_bit_structure(struct drm_device *dev, struct bios *bios, const uint16_t bitoffset)
{
	int entries = bios->data[bitoffset + 4];
	/* parse i first, I next (which needs C & M before it), and L before D */
	char parseorder[] = "iCMILDT";
	struct bit_entry bitentry;
	int i, j, offset;

	for (i = 0; i < sizeof(parseorder); i++) {
		for (j = 0, offset = bitoffset + 6; j < entries; j++, offset += 6) {
			bitentry.id[0] = bios->data[offset];
			bitentry.id[1] = bios->data[offset + 1];
			bitentry.length = le16_to_cpu(*((uint16_t *)&bios->data[offset + 2]));
			bitentry.offset = le16_to_cpu(*((uint16_t *)&bios->data[offset + 4]));

			if (bitentry.id[0] != parseorder[i])
				continue;

			switch (bitentry.id[0]) {
			case 'C':
				parse_bit_C_tbl_entry(dev, bios, &bitentry);
				break;
			}
		}
	}
}

static uint16_t findstr(uint8_t *data, int n, const uint8_t *str, int len)
{
	int i, j;

	for (i = 0; i <= (n - len); i++) {
		for (j = 0; j < len; j++)
			if (data[i + j] != str[j])
				break;
		if (j == len)
			return i;
	}

	return 0;
}

static void
read_dcb_i2c_entry(struct drm_device *dev, uint8_t dcb_version, uint16_t i2ctabptr, int index)
{
	struct drm_nouveau_private *dev_priv = dev->dev_private;
	struct bios *bios = &dev_priv->bios;
	uint8_t *i2ctable = &bios->data[i2ctabptr];
	uint8_t headerlen = 0;
	int i2c_entries = MAX_NUM_DCB_ENTRIES;
	int recordoffset = 0, rdofs = 1, wrofs = 0;

	if (!i2ctabptr)
		return;

	if (dcb_version >= 0x30) {
		if (i2ctable[0] != dcb_version) /* necessary? */
			DRM_ERROR(
				   "DCB I2C table version mismatch (%02X vs %02X)\n",
				   i2ctable[0], dcb_version);
		headerlen = i2ctable[1];
		i2c_entries = i2ctable[2];

		/* same address offset used for read and write for C51 and G80 */
		if (bios->chip_version == 0x51)
			rdofs = wrofs = 1;
		if (i2ctable[0] >= 0x40)
			rdofs = wrofs = 0;
	}
	/* it's your own fault if you call this function on a DCB 1.1 BIOS --
	 * the test below is for DCB 1.2
	 */
	if (dcb_version < 0x14) {
		recordoffset = 2;
		rdofs = 0;
		wrofs = 1;
	}

	if (index == 0xf)
		return;
	if (index > i2c_entries) {
		DRM_ERROR(
			   "DCB I2C index too big (%d > %d)\n",
			   index, i2ctable[2]);
		return;
	}
	if (i2ctable[headerlen + 4 * index + 3] == 0xff) {
		DRM_ERROR(
			   "DCB I2C entry invalid\n");
		return;
	}

	if (bios->chip_version == 0x51) {
		int port_type = i2ctable[headerlen + 4 * index + 3];

		if (port_type != 4)
			DRM_ERROR(
				   "DCB I2C table has port type %d\n", port_type);
	}
	if (i2ctable[0] >= 0x40) {
		int port_type = i2ctable[headerlen + 4 * index + 3];

		if (port_type != 5)
			DRM_ERROR(
				   "DCB I2C table has port type %d\n", port_type);
	}

	dev_priv->dcb_table.i2c_read[index] = i2ctable[headerlen + recordoffset + rdofs + 4 * index];
	dev_priv->dcb_table.i2c_write[index] = i2ctable[headerlen + recordoffset + wrofs + 4 * index];
}

static bool
parse_dcb_entry(struct drm_device *dev, int index, uint8_t dcb_version, uint16_t i2ctabptr, uint32_t conn, uint32_t conf)
{
	struct drm_nouveau_private *dev_priv = dev->dev_private;
	struct dcb_entry *entry = &dev_priv->dcb_table.entry[index];

	memset(entry, 0, sizeof (struct dcb_entry));

	entry->index = index;
	/* safe defaults for a crt */
	entry->type = 0;
	entry->i2c_index = 0;
	entry->heads = 1;
	entry->bus = 0;
	entry->location = LOC_ON_CHIP;
	entry->or = 1;
	entry->duallink_possible = false;

	if (dcb_version >= 0x20) {
		entry->type = conn & 0xf;
		entry->i2c_index = (conn >> 4) & 0xf;
		entry->heads = (conn >> 8) & 0xf;
		entry->bus = (conn >> 16) & 0xf;
		entry->location = (conn >> 20) & 0xf;
		entry->or = (conn >> 24) & 0xf;
		/* Normal entries consist of a single bit, but dual link has the
		 * adjacent more significant bit set too
		 */
		if ((1 << (ffs(entry->or) - 1)) * 3 == entry->or)
			entry->duallink_possible = true;

		switch (entry->type) {
		case DCB_OUTPUT_LVDS:
			{
			uint32_t mask;
			if (conf & 0x1)
				entry->lvdsconf.use_straps_for_mode = true;
			if (dcb_version < 0x22) {
				mask = ~0xd;
				/* both 0x4 and 0x8 show up in v2.0 tables; assume they mean
				 * the same thing, which is probably wrong, but might work */
				if (conf & 0x4 || conf & 0x8)
					entry->lvdsconf.use_power_scripts = true;
			} else {
				mask = ~0x5;
				if (conf & 0x4)
					entry->lvdsconf.use_power_scripts = true;
			}
			if (conf & mask) {
				DRM_ERROR(
					   "Unknown LVDS configuration bits, please report\n");
				/* cause output setting to fail, so message is seen */
				dev_priv->dcb_table.entries = 0;
				return false;
			}
			break;
			}
		case 0xe:
			/* weird type that appears on g80 mobile bios; nv driver treats it as a terminator */
			return false;
		}
		read_dcb_i2c_entry(dev, dcb_version, i2ctabptr, entry->i2c_index);
	} else if (dcb_version >= 0x14 ) {
		if (conn != 0xf0003f00 && conn != 0xf2247f10 && conn != 0xf2204001 && conn != 0xf2204301 && conn != 0xf2244311 && conn != 0xf2045f14 && conn != 0xf2205004 && conn != 0xf2208001 && conn != 0xf4204011 && conn != 0xf4208011 && conn != 0xf4248011) {
			DRM_ERROR(
				   "Unknown DCB 1.4 / 1.5 entry, please report\n");
			/* cause output setting to fail, so message is seen */
			dev_priv->dcb_table.entries = 0;
			return false;
		}
		/* most of the below is a "best guess" atm */
		entry->type = conn & 0xf;
		if (entry->type == 4) { /* digital */
			if (conn & 0x10)
				entry->type = DCB_OUTPUT_LVDS;
			else
				entry->type = DCB_OUTPUT_TMDS;
		}
		/* what's in bits 5-13? could be some brooktree/chrontel/philips thing, in tv case */
		entry->i2c_index = (conn >> 14) & 0xf;
		/* raw heads field is in range 0-1, so move to 1-2 */
		entry->heads = ((conn >> 18) & 0x7) + 1;
		entry->location = (conn >> 21) & 0xf;
		entry->bus = (conn >> 25) & 0x7;
		/* set or to be same as heads -- hopefully safe enough */
		entry->or = entry->heads;

		switch (entry->type) {
		case DCB_OUTPUT_LVDS:
			/* this is probably buried in conn's unknown bits */
			entry->lvdsconf.use_power_scripts = true;
			break;
		case DCB_OUTPUT_TMDS:
			/* invent a DVI-A output, by copying the fields of the DVI-D output
			 * reported to work by math_b on an NV20(!) */
			memcpy(&entry[1], &entry[0], sizeof(struct dcb_entry));
			entry[1].type = DCB_OUTPUT_ANALOG;
			dev_priv->dcb_table.entries++;
		}
		read_dcb_i2c_entry(dev, dcb_version, i2ctabptr, entry->i2c_index);
	} else if (dcb_version >= 0x12) {
		/* v1.2 tables normally have the same 5 entries, which are not
		 * specific to the card, so use the defaults for a crt */
		/* DCB v1.2 does have an I2C table that read_dcb_i2c_table can handle, but cards
		 * exist (seen on nv11) where the pointer to the table points to the wrong
		 * place, so for now, we rely on the indices parsed in parse_bmp_structure
		 */
		entry->i2c_index = dev_priv->bios.legacy.i2c_indices.crt;
	} else { /* pre DCB / v1.1 - use the safe defaults for a crt */
		DRM_ERROR(
			   "No information in BIOS output table; assuming a CRT output exists\n");
		entry->i2c_index = dev_priv->bios.legacy.i2c_indices.crt;
	}

	if (entry->type == DCB_OUTPUT_LVDS && dev_priv->bios.fp.strapping != 0xff)
		entry->lvdsconf.use_straps_for_mode = true;

	dev_priv->dcb_table.entries++;

	return true;
}

static void merge_like_dcb_entries(struct drm_device *dev)
{
	struct drm_nouveau_private *dev_priv = dev->dev_private;

	/* DCB v2.0 lists each output combination separately.
	 * Here we merge compatible entries to have fewer outputs, with more options
	 */
	int i, newentries = 0;

	for (i = 0; i < dev_priv->dcb_table.entries; i++) {
		struct dcb_entry *ient = &dev_priv->dcb_table.entry[i];
		int j;

		for (j = i + 1; j < dev_priv->dcb_table.entries; j++) {
			struct dcb_entry *jent = &dev_priv->dcb_table.entry[j];

			if (jent->type == 100) /* already merged entry */
				continue;

			/* merge heads field when all other fields the same */
			if (jent->i2c_index == ient->i2c_index && jent->type == ient->type && jent->location == ient->location && jent->or == ient->or) {
				DRM_INFO(
					   "Merging DCB entries %d and %d\n", i, j);
				ient->heads |= jent->heads;
				jent->type = 100; /* dummy value */
			}
		}
	}

	/* Compact entries merged into others out of dcb_table */
	for (i = 0; i < dev_priv->dcb_table.entries; i++) {
		if ( dev_priv->dcb_table.entry[i].type == 100 )
			continue;

		if (newentries != i)
			memcpy(&dev_priv->dcb_table.entry[newentries], &dev_priv->dcb_table.entry[i], sizeof(struct dcb_entry));
		newentries++;
	}

	dev_priv->dcb_table.entries = newentries;
}

static unsigned int parse_dcb_table(struct drm_device *dev, struct bios *bios)
{
	struct drm_nouveau_private *dev_priv = dev->dev_private;
	uint16_t dcbptr, i2ctabptr = 0;
	uint8_t *dcbtable;
	uint8_t dcb_version, headerlen = 0x4, entries = MAX_NUM_DCB_ENTRIES;
	bool configblock = true;
	int recordlength = 8, confofs = 4;
	int i;

	dev_priv->dcb_table.entries = 0;

	/* get the offset from 0x36 */
	dcbptr = le16_to_cpu(*(uint16_t *)&bios->data[0x36]);

	if (dcbptr == 0x0) {
		DRM_ERROR(
			   "No Display Configuration Block pointer found\n");
		/* this situation likely means a really old card, pre DCB, so we'll add the safe CRT entry */
		parse_dcb_entry(dev, 0, 0, 0, 0, 0);
		return 1;
	}

	dcbtable = &bios->data[dcbptr];

	/* get DCB version */
	dcb_version = dcbtable[0];
	DRM_INFO(
		   "Display Configuration Block version %d.%d found\n",
		   dcb_version >> 4, dcb_version & 0xf);

	if (dcb_version >= 0x20) { /* NV17+ */
		uint32_t sig;

		if (dcb_version >= 0x30) { /* NV40+ */
			headerlen = dcbtable[1];
			entries = dcbtable[2];
			recordlength = dcbtable[3];
			i2ctabptr = le16_to_cpu(*(uint16_t *)&dcbtable[4]);
			sig = le32_to_cpu(*(uint32_t *)&dcbtable[6]);

			DRM_INFO(
				   "DCB header length %d, with %d possible entries\n",
				   headerlen, entries);
		} else {
			i2ctabptr = le16_to_cpu(*(uint16_t *)&dcbtable[2]);
			sig = le32_to_cpu(*(uint32_t *)&dcbtable[4]);
			headerlen = 8;
		}

		if (sig != 0x4edcbdcb) {
			DRM_ERROR(
				   "Bad Display Configuration Block signature (%08X)\n", sig);
			return 0;
		}
	} else if (dcb_version >= 0x14) { /* some NV15/16, and NV11+ */
		char sig[8];

		memset(sig, 0, 8);
		strncpy(sig, (char *)&dcbtable[-7], 7);
		i2ctabptr = le16_to_cpu(*(uint16_t *)&dcbtable[2]);
		recordlength = 10;
		confofs = 6;

		if (strcmp(sig, "DEV_REC")) {
			DRM_ERROR(
				   "Bad Display Configuration Block signature (%s)\n", sig);
			return 0;
		}
	} else if (dcb_version >= 0x12) { /* some NV6/10, and NV15+ */
		i2ctabptr = le16_to_cpu(*(uint16_t *)&dcbtable[2]);
		configblock = false;
	} else {	/* NV5+, maybe NV4 */
		/* DCB 1.1 seems to be quite unhelpful - we'll just add the safe CRT entry */
		parse_dcb_entry(dev, 0, dcb_version, 0, 0, 0);
		return 1;
	}

	if (entries >= MAX_NUM_DCB_ENTRIES)
		entries = MAX_NUM_DCB_ENTRIES;

	for (i = 0; i < entries; i++) {
		uint32_t connection, config = 0;

		connection = le32_to_cpu(*(uint32_t *)&dcbtable[headerlen + recordlength * i]);
		if (configblock)
			config = le32_to_cpu(*(uint32_t *)&dcbtable[headerlen + confofs + recordlength * i]);

		/* Should we allow discontinuous DCBs? Certainly DCB I2C tables can be discontinuous */
		if ((connection & 0x0000000f) == 0x0000000f) /* end of records */
			break;
		if (connection == 0x00000000) /* seen on an NV11 with DCB v1.5 */
			break;

		DRM_INFO("Raw DCB entry %d: %08x %08x\n", i, connection, config);
		if (!parse_dcb_entry(dev, dev_priv->dcb_table.entries, dcb_version, i2ctabptr, connection, config))
			break;
	}

	merge_like_dcb_entries(dev);

	return dev_priv->dcb_table.entries;
}

int nouveau_parse_bios(struct drm_device *dev)
{
	struct drm_nouveau_private *dev_priv = dev->dev_private;

	const uint8_t bit_signature[] = { 'B', 'I', 'T' };
	int offset;

	dev_priv->bios.data = kzalloc(NV50_PROM__ESIZE, GFP_KERNEL);
	if (!dev_priv->bios.data)
		return -ENOMEM;

	if (!nv_shadow_bios(dev, dev_priv->bios.data))
		return -EINVAL;

	dev_priv->bios.length = dev_priv->bios.data[2] * 512;
	if (dev_priv->bios.length > NV50_PROM__ESIZE)
		dev_priv->bios.length = NV50_PROM__ESIZE;

	if ((offset = findstr(dev_priv->bios.data, dev_priv->bios.length, bit_signature, sizeof(bit_signature)))) {
		DRM_INFO("BIT BIOS found\n");
		parse_bit_structure(dev, &dev_priv->bios, offset + 4);
	} else {
		DRM_ERROR("BIT BIOS not found\n");
		return -EINVAL;
	}

	if (parse_dcb_table(dev, &dev_priv->bios))
		DRM_INFO("Found %d entries in DCB\n", dev_priv->dcb_table.entries);

	return 0;
}

/* temporary */
#define NV_RAMDAC_NVPLL			0x00680500
#define NV_RAMDAC_MPLL			0x00680504
#define NV_RAMDAC_VPLL			0x00680508
#	define NV_RAMDAC_PLL_COEFF_MDIV			0x000000FF
#	define NV_RAMDAC_PLL_COEFF_NDIV			0x0000FF00
#	define NV_RAMDAC_PLL_COEFF_PDIV			0x00070000
#	define NV30_RAMDAC_ENABLE_VCO2			(1 << 7)
#define NV_RAMDAC_VPLL2			0x00680520

bool get_pll_limits(struct drm_device *dev, uint32_t limit_match, struct pll_lims *pll_lim)
{
	/* PLL limits table
	 *
	 * Version 0x10: NV31
	 * One byte header (version), one record of 24 bytes
	 * Version 0x11: NV36 - Not implemented
	 * Seems to have same record style as 0x10, but 3 records rather than 1
	 * Version 0x20: Found on Geforce 6 cards
	 * Trivial 4 byte BIT header. 31 (0x1f) byte record length
	 * Version 0x21: Found on Geforce 7, 8 and some Geforce 6 cards
	 * 5 byte header, fifth byte of unknown purpose. 35 (0x23) byte record
	 * length in general, some (integrated) have an extra configuration byte
	 */

	struct drm_nouveau_private *dev_priv = dev->dev_private;
	struct bios *bios = &dev_priv->bios;
	uint8_t pll_lim_ver = 0, headerlen = 0, recordlen = 0, entries = 0;
	int pllindex = 0;
	uint32_t crystal_strap_mask, crystal_straps;

	if (!bios->pll_limit_tbl_ptr) {
		if (bios->chip_version >= 0x40 || bios->chip_version == 0x31 || bios->chip_version == 0x36) {
			DRM_ERROR("Pointer to PLL limits table invalid\n");
			return false;
		}
	} else {
		pll_lim_ver = bios->data[bios->pll_limit_tbl_ptr];

		DRM_INFO("Found PLL limits table version 0x%X\n", pll_lim_ver);
	}

	crystal_strap_mask = 1 << 6;
	/* open coded pNv->twoHeads test */
	if (bios->chip_version > 0x10 && bios->chip_version != 0x15 &&
		bios->chip_version != 0x1a && bios->chip_version != 0x20)
		crystal_strap_mask |= 1 << 22;
	crystal_straps = NV_READ(NV50_PEXTDEV + 0x0) & crystal_strap_mask;

	switch (pll_lim_ver) {
	/* we use version 0 to indicate a pre limit table bios (single stage pll)
	 * and load the hard coded limits instead */
	case 0:
		break;
	case 0x10:
	case 0x11: /* strictly v0x11 has 3 entries, but the last two don't seem to get used */
		headerlen = 1;
		recordlen = 0x18;
		entries = 1;
		pllindex = 0;
		break;
	case 0x20:
	case 0x21:
		headerlen = bios->data[bios->pll_limit_tbl_ptr + 1];
		recordlen = bios->data[bios->pll_limit_tbl_ptr + 2];
		entries = bios->data[bios->pll_limit_tbl_ptr + 3];
		break;
	default:
		DRM_ERROR("PLL limits table revision not currently supported\n");
		return false;
	}

	/* initialize all members to zero */
	memset(pll_lim, 0, sizeof(struct pll_lims));

	if (pll_lim_ver == 0x10 || pll_lim_ver == 0x11) {
		uint16_t plloffs = bios->pll_limit_tbl_ptr + headerlen + recordlen * pllindex;

		pll_lim->vco1.minfreq = le32_to_cpu(*((uint32_t *)(&bios->data[plloffs])));
		pll_lim->vco1.maxfreq = le32_to_cpu(*((uint32_t *)(&bios->data[plloffs + 4])));
		pll_lim->vco2.minfreq = le32_to_cpu(*((uint32_t *)(&bios->data[plloffs + 8])));
		pll_lim->vco2.maxfreq = le32_to_cpu(*((uint32_t *)(&bios->data[plloffs + 12])));
		pll_lim->vco1.min_inputfreq = le32_to_cpu(*((uint32_t *)(&bios->data[plloffs + 16])));
		pll_lim->vco2.min_inputfreq = le32_to_cpu(*((uint32_t *)(&bios->data[plloffs + 20])));
		pll_lim->vco1.max_inputfreq = pll_lim->vco2.max_inputfreq = INT_MAX;

		/* these values taken from nv30/31/36 */
		pll_lim->vco1.min_n = 0x1;
		if (bios->chip_version == 0x36)
			pll_lim->vco1.min_n = 0x5;
		pll_lim->vco1.max_n = 0xff;
		pll_lim->vco1.min_m = 0x1;
		pll_lim->vco1.max_m = 0xd;
		pll_lim->vco2.min_n = 0x4;
		/* on nv30, 31, 36 (i.e. all cards with two stage PLLs with this
		 * table version (apart from nv35)), N2 is compared to
		 * maxN2 (0x46) and 10 * maxM2 (0x4), so set maxN2 to 0x28 and
		 * save a comparison
		 */
		pll_lim->vco2.max_n = 0x28;
		if (bios->chip_version == 0x30 || bios->chip_version == 0x35)
		       /* only 5 bits available for N2 on nv30/35 */
			pll_lim->vco2.max_n = 0x1f;
		pll_lim->vco2.min_m = 0x1;
		pll_lim->vco2.max_m = 0x4;
	} else if (pll_lim_ver) {	/* ver 0x20, 0x21 */
		uint16_t plloffs = bios->pll_limit_tbl_ptr + headerlen;
		uint32_t reg = 0; /* default match */
		int i;

		/* first entry is default match, if nothing better. warn if reg field nonzero */
		if (le32_to_cpu(*((uint32_t *)&bios->data[plloffs])))
			DRM_ERROR("Default PLL limit entry has non-zero register field\n");

		if (limit_match > MAX_PLL_TYPES)
			/* we've been passed a reg as the match */
			reg = limit_match;
		else /* limit match is a pll type */
			for (i = 1; i < entries && !reg; i++) {
				uint32_t cmpreg = le32_to_cpu(*((uint32_t *)(&bios->data[plloffs + recordlen * i])));

				if (limit_match == NVPLL && (cmpreg == NV_RAMDAC_NVPLL || cmpreg == 0x4000))
					reg = cmpreg;
				if (limit_match == MPLL && (cmpreg == NV_RAMDAC_MPLL || cmpreg == 0x4020))
					reg = cmpreg;
				if (limit_match == VPLL1 && (cmpreg == NV_RAMDAC_VPLL || cmpreg == 0x4010))
					reg = cmpreg;
				if (limit_match == VPLL2 && (cmpreg == NV_RAMDAC_VPLL2 || cmpreg == 0x4018))
					reg = cmpreg;
			}

		for (i = 1; i < entries; i++)
			if (le32_to_cpu(*((uint32_t *)&bios->data[plloffs + recordlen * i])) == reg) {
				pllindex = i;
				break;
			}

		plloffs += recordlen * pllindex;

		DRM_INFO("Loading PLL limits for reg 0x%08x\n", pllindex ? reg : 0);

		/* frequencies are stored in tables in MHz, kHz are more useful, so we convert */

		/* What output frequencies can each VCO generate? */
		pll_lim->vco1.minfreq = le16_to_cpu(*((uint16_t *)(&bios->data[plloffs + 4]))) * 1000;
		pll_lim->vco1.maxfreq = le16_to_cpu(*((uint16_t *)(&bios->data[plloffs + 6]))) * 1000;
		pll_lim->vco2.minfreq = le16_to_cpu(*((uint16_t *)(&bios->data[plloffs + 8]))) * 1000;
		pll_lim->vco2.maxfreq = le16_to_cpu(*((uint16_t *)(&bios->data[plloffs + 10]))) * 1000;

		/* What input frequencies do they accept (past the m-divider)? */
		pll_lim->vco1.min_inputfreq = le16_to_cpu(*((uint16_t *)(&bios->data[plloffs + 12]))) * 1000;
		pll_lim->vco2.min_inputfreq = le16_to_cpu(*((uint16_t *)(&bios->data[plloffs + 14]))) * 1000;
		pll_lim->vco1.max_inputfreq = le16_to_cpu(*((uint16_t *)(&bios->data[plloffs + 16]))) * 1000;
		pll_lim->vco2.max_inputfreq = le16_to_cpu(*((uint16_t *)(&bios->data[plloffs + 18]))) * 1000;

		/* What values are accepted as multiplier and divider? */
		pll_lim->vco1.min_n = bios->data[plloffs + 20];
		pll_lim->vco1.max_n = bios->data[plloffs + 21];
		pll_lim->vco1.min_m = bios->data[plloffs + 22];
		pll_lim->vco1.max_m = bios->data[plloffs + 23];
		pll_lim->vco2.min_n = bios->data[plloffs + 24];
		pll_lim->vco2.max_n = bios->data[plloffs + 25];
		pll_lim->vco2.min_m = bios->data[plloffs + 26];
		pll_lim->vco2.max_m = bios->data[plloffs + 27];

		pll_lim->unk1c = bios->data[plloffs + 28];
		pll_lim->max_log2p_bias = bios->data[plloffs + 29];
		pll_lim->log2p_bias = bios->data[plloffs + 30];

		if (recordlen > 0x22)
			pll_lim->refclk = le32_to_cpu(*((uint32_t *)&bios->data[plloffs + 31]));

		if (recordlen > 0x23)
			if (bios->data[plloffs + 35])
				DRM_ERROR("Bits set in PLL configuration byte (%x)\n", bios->data[plloffs + 35]);

		/* C51 special not seen elsewhere */
		/*if (bios->chip_version == 0x51 && !pll_lim->refclk) {
			uint32_t sel_clk = nv32_rd(pScrn, NV_RAMDAC_SEL_CLK);

			if (((limit_match == NV_RAMDAC_VPLL || limit_match == VPLL1) && sel_clk & 0x20) ||
			    ((limit_match == NV_RAMDAC_VPLL2 || limit_match == VPLL2) && sel_clk & 0x80)) {
				if (nv_idx_port_rd(pScrn, CRTC_INDEX_COLOR, NV_VGA_CRTCX_REVISION) < 0xa3)
					pll_lim->refclk = 200000;
				else
					pll_lim->refclk = 25000;
			}
		}*/
	}

	/* By now any valid limit table ought to have set a max frequency for
	 * vco1, so if it's zero it's either a pre limit table bios, or one
	 * with an empty limit table (seen on nv18)
	 */
	if (!pll_lim->vco1.maxfreq) {
		pll_lim->vco1.minfreq = bios->fminvco;
		pll_lim->vco1.maxfreq = bios->fmaxvco;
		pll_lim->vco1.min_inputfreq = 0;
		pll_lim->vco1.max_inputfreq = INT_MAX;
		pll_lim->vco1.min_n = 0x1;
		pll_lim->vco1.max_n = 0xff;
		pll_lim->vco1.min_m = 0x1;
		if (crystal_straps == 0) {
			/* nv05 does this, nv11 doesn't, nv10 unknown */
			if (bios->chip_version < 0x11)
				pll_lim->vco1.min_m = 0x7;
			pll_lim->vco1.max_m = 0xd;
		} else {
			if (bios->chip_version < 0x11)
				pll_lim->vco1.min_m = 0x8;
			pll_lim->vco1.max_m = 0xe;
		}
	}

	if (!pll_lim->refclk)
		switch (crystal_straps) {
		case 0:
			pll_lim->refclk = 13500;
			break;
		case (1 << 6):
			pll_lim->refclk = 14318;
			break;
		case (1 << 22):
			pll_lim->refclk = 27000;
			break;
		case (1 << 22 | 1 << 6):
			pll_lim->refclk = 25000;
			break;
		}

#if 1 /* for easy debugging */
	DRM_INFO("pll.vco1.minfreq: %d\n", pll_lim->vco1.minfreq);
	DRM_INFO("pll.vco1.maxfreq: %d\n", pll_lim->vco1.maxfreq);
	DRM_INFO("pll.vco2.minfreq: %d\n", pll_lim->vco2.minfreq);
	DRM_INFO("pll.vco2.maxfreq: %d\n", pll_lim->vco2.maxfreq);

	DRM_INFO("pll.vco1.min_inputfreq: %d\n", pll_lim->vco1.min_inputfreq);
	DRM_INFO("pll.vco1.max_inputfreq: %d\n", pll_lim->vco1.max_inputfreq);
	DRM_INFO("pll.vco2.min_inputfreq: %d\n", pll_lim->vco2.min_inputfreq);
	DRM_INFO("pll.vco2.max_inputfreq: %d\n", pll_lim->vco2.max_inputfreq);

	DRM_INFO("pll.vco1.min_n: %d\n", pll_lim->vco1.min_n);
	DRM_INFO("pll.vco1.max_n: %d\n", pll_lim->vco1.max_n);
	DRM_INFO("pll.vco1.min_m: %d\n", pll_lim->vco1.min_m);
	DRM_INFO("pll.vco1.max_m: %d\n", pll_lim->vco1.max_m);
	DRM_INFO("pll.vco2.min_n: %d\n", pll_lim->vco2.min_n);
	DRM_INFO("pll.vco2.max_n: %d\n", pll_lim->vco2.max_n);
	DRM_INFO("pll.vco2.min_m: %d\n", pll_lim->vco2.min_m);
	DRM_INFO("pll.vco2.max_m: %d\n", pll_lim->vco2.max_m);

	DRM_INFO("pll.unk1c: %d\n", pll_lim->unk1c);
	DRM_INFO("pll.max_log2p_bias: %d\n", pll_lim->max_log2p_bias);
	DRM_INFO("pll.log2p_bias: %d\n", pll_lim->log2p_bias);

	DRM_INFO("pll.refclk: %d\n", pll_lim->refclk);
#endif

	return true;
}