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/*

 * Copyright © 2006 Intel Corporation

 *

 * 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 AUTHORS OR COPYRIGHT HOLDERS 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.

 *

 * Authors:

 *    Eric Anholt 

 *

 */

#include 

#include 

#include 

#include "i915_drv.h"

#include "intel_bios.h"

#define	SLAVE_ADDR1	0x70

#define	SLAVE_ADDR2	0x72

static int panel_type;

static void *

find_section(struct bdb_header *bdb, int section_id)

{

	u8 *base = (u8 *)bdb;

	int index = 0;

	u16 total, current_size;

	u8 current_id;

	/* skip to first section */

	index += bdb->header_size;

	total = bdb->bdb_size;

	/* walk the sections looking for section_id */

	while (index < total) {

		current_id = *(base + index);

		index++;

		current_size = *((u16 *)(base + index));

		index += 2;

		if (current_id == section_id)

			return base + index;

		index += current_size;

	}

	return NULL;

}

static u16

get_blocksize(void *p)

{

	u16 *block_ptr, block_size;

	block_ptr = (u16 *)((char *)p - 2);

	block_size = *block_ptr;

	return block_size;

}

static void

fill_detail_timing_data(struct drm_display_mode *panel_fixed_mode,

			const struct lvds_dvo_timing *dvo_timing)

{

	panel_fixed_mode->hdisplay = (dvo_timing->hactive_hi << 8) |

		dvo_timing->hactive_lo;

	panel_fixed_mode->hsync_start = panel_fixed_mode->hdisplay +

		((dvo_timing->hsync_off_hi << 8) | dvo_timing->hsync_off_lo);

	panel_fixed_mode->hsync_end = panel_fixed_mode->hsync_start +

		dvo_timing->hsync_pulse_width;

	panel_fixed_mode->htotal = panel_fixed_mode->hdisplay +

		((dvo_timing->hblank_hi << 8) | dvo_timing->hblank_lo);

	panel_fixed_mode->vdisplay = (dvo_timing->vactive_hi << 8) |

		dvo_timing->vactive_lo;

	panel_fixed_mode->vsync_start = panel_fixed_mode->vdisplay +

		dvo_timing->vsync_off;

	panel_fixed_mode->vsync_end = panel_fixed_mode->vsync_start +

		dvo_timing->vsync_pulse_width;

	panel_fixed_mode->vtotal = panel_fixed_mode->vdisplay +

		((dvo_timing->vblank_hi << 8) | dvo_timing->vblank_lo);

	panel_fixed_mode->clock = dvo_timing->clock * 10;

	panel_fixed_mode->type = DRM_MODE_TYPE_PREFERRED;

	if (dvo_timing->hsync_positive)

		panel_fixed_mode->flags |= DRM_MODE_FLAG_PHSYNC;

	else

		panel_fixed_mode->flags |= DRM_MODE_FLAG_NHSYNC;

	if (dvo_timing->vsync_positive)

		panel_fixed_mode->flags |= DRM_MODE_FLAG_PVSYNC;

	else

		panel_fixed_mode->flags |= DRM_MODE_FLAG_NVSYNC;

	/* Some VBTs have bogus h/vtotal values */

	if (panel_fixed_mode->hsync_end > panel_fixed_mode->htotal)

		panel_fixed_mode->htotal = panel_fixed_mode->hsync_end + 1;

	if (panel_fixed_mode->vsync_end > panel_fixed_mode->vtotal)

		panel_fixed_mode->vtotal = panel_fixed_mode->vsync_end + 1;

	drm_mode_set_name(panel_fixed_mode);

}

static bool

lvds_dvo_timing_equal_size(const struct lvds_dvo_timing *a,

			   const struct lvds_dvo_timing *b)

{

	if (a->hactive_hi != b->hactive_hi ||

	    a->hactive_lo != b->hactive_lo)

		return false;

	if (a->hsync_off_hi != b->hsync_off_hi ||

	    a->hsync_off_lo != b->hsync_off_lo)

		return false;

	if (a->hsync_pulse_width != b->hsync_pulse_width)

		return false;

	if (a->hblank_hi != b->hblank_hi ||

	    a->hblank_lo != b->hblank_lo)

		return false;

	if (a->vactive_hi != b->vactive_hi ||

	    a->vactive_lo != b->vactive_lo)

		return false;

	if (a->vsync_off != b->vsync_off)

		return false;

	if (a->vsync_pulse_width != b->vsync_pulse_width)

		return false;

	if (a->vblank_hi != b->vblank_hi ||

	    a->vblank_lo != b->vblank_lo)

		return false;

	return true;

}

static const struct lvds_dvo_timing *

get_lvds_dvo_timing(const struct bdb_lvds_lfp_data *lvds_lfp_data,

		    const struct bdb_lvds_lfp_data_ptrs *lvds_lfp_data_ptrs,

		    int index)

{

	/*

	 * the size of fp_timing varies on the different platform.

	 * So calculate the DVO timing relative offset in LVDS data

	 * entry to get the DVO timing entry

	 */

	int lfp_data_size =

		lvds_lfp_data_ptrs->ptr[1].dvo_timing_offset -

		lvds_lfp_data_ptrs->ptr[0].dvo_timing_offset;

	int dvo_timing_offset =

		lvds_lfp_data_ptrs->ptr[0].dvo_timing_offset -

		lvds_lfp_data_ptrs->ptr[0].fp_timing_offset;

	char *entry = (char *)lvds_lfp_data->data + lfp_data_size * index;

	return (struct lvds_dvo_timing *)(entry + dvo_timing_offset);

}

/* get lvds_fp_timing entry

 * this function may return NULL if the corresponding entry is invalid

 */

static const struct lvds_fp_timing *

get_lvds_fp_timing(const struct bdb_header *bdb,

		   const struct bdb_lvds_lfp_data *data,

		   const struct bdb_lvds_lfp_data_ptrs *ptrs,

		   int index)

{

	size_t data_ofs = (const u8 *)data - (const u8 *)bdb;

	u16 data_size = ((const u16 *)data)[-1]; /* stored in header */

	size_t ofs;

	if (index >= ARRAY_SIZE(ptrs->ptr))

		return NULL;

	ofs = ptrs->ptr[index].fp_timing_offset;

	if (ofs < data_ofs ||

	    ofs + sizeof(struct lvds_fp_timing) > data_ofs + data_size)

		return NULL;

	return (const struct lvds_fp_timing *)((const u8 *)bdb + ofs);

}

/* Try to find integrated panel data */

static void

parse_lfp_panel_data(struct drm_i915_private *dev_priv,

			    struct bdb_header *bdb)

{

	const struct bdb_lvds_options *lvds_options;

	const struct bdb_lvds_lfp_data *lvds_lfp_data;

	const struct bdb_lvds_lfp_data_ptrs *lvds_lfp_data_ptrs;

	const struct lvds_dvo_timing *panel_dvo_timing;

	const struct lvds_fp_timing *fp_timing;

	struct drm_display_mode *panel_fixed_mode;

	int i, downclock;

	lvds_options = find_section(bdb, BDB_LVDS_OPTIONS);

	if (!lvds_options)

		return;

	dev_priv->lvds_dither = lvds_options->pixel_dither;

	if (lvds_options->panel_type == 0xff)

		return;

	panel_type = lvds_options->panel_type;

	lvds_lfp_data = find_section(bdb, BDB_LVDS_LFP_DATA);

	if (!lvds_lfp_data)

		return;

	lvds_lfp_data_ptrs = find_section(bdb, BDB_LVDS_LFP_DATA_PTRS);

	if (!lvds_lfp_data_ptrs)

		return;

	dev_priv->lvds_vbt = 1;

	panel_dvo_timing = get_lvds_dvo_timing(lvds_lfp_data,

					       lvds_lfp_data_ptrs,

					       lvds_options->panel_type);

	panel_fixed_mode = kzalloc(sizeof(*panel_fixed_mode), GFP_KERNEL);

	if (!panel_fixed_mode)

		return;

	fill_detail_timing_data(panel_fixed_mode, panel_dvo_timing);

	dev_priv->lfp_lvds_vbt_mode = panel_fixed_mode;

	DRM_DEBUG_KMS("Found panel mode in BIOS VBT tables:\n");

	drm_mode_debug_printmodeline(panel_fixed_mode);

	/*

	 * Iterate over the LVDS panel timing info to find the lowest clock

	 * for the native resolution.

	 */

	downclock = panel_dvo_timing->clock;

	for (i = 0; i < 16; i++) {

		const struct lvds_dvo_timing *dvo_timing;

		dvo_timing = get_lvds_dvo_timing(lvds_lfp_data,

						 lvds_lfp_data_ptrs,

						 i);

		if (lvds_dvo_timing_equal_size(dvo_timing, panel_dvo_timing) &&

		    dvo_timing->clock < downclock)

			downclock = dvo_timing->clock;

	}

	if (downclock < panel_dvo_timing->clock && i915_lvds_downclock) {

		dev_priv->lvds_downclock_avail = 1;

		dev_priv->lvds_downclock = downclock * 10;

		DRM_DEBUG_KMS("LVDS downclock is found in VBT. "

			      "Normal Clock %dKHz, downclock %dKHz\n",

			      panel_fixed_mode->clock, 10*downclock);

	}

	fp_timing = get_lvds_fp_timing(bdb, lvds_lfp_data,

				       lvds_lfp_data_ptrs,

				       lvds_options->panel_type);

	if (fp_timing) {

		/* check the resolution, just to be sure */

		if (fp_timing->x_res == panel_fixed_mode->hdisplay &&

		    fp_timing->y_res == panel_fixed_mode->vdisplay) {

			dev_priv->bios_lvds_val = fp_timing->lvds_reg_val;

			DRM_DEBUG_KMS("VBT initial LVDS value %x\n",

				      dev_priv->bios_lvds_val);

		}

	}

}

/* Try to find sdvo panel data */

static void

parse_sdvo_panel_data(struct drm_i915_private *dev_priv,

		      struct bdb_header *bdb)

{

	struct lvds_dvo_timing *dvo_timing;

	struct drm_display_mode *panel_fixed_mode;

	int index;

	index = i915_vbt_sdvo_panel_type;

	if (index == -2) {

		DRM_DEBUG_KMS("Ignore SDVO panel mode from BIOS VBT tables.\n");

		return;

	}

	if (index == -1) {

		struct bdb_sdvo_lvds_options *sdvo_lvds_options;

		sdvo_lvds_options = find_section(bdb, BDB_SDVO_LVDS_OPTIONS);

		if (!sdvo_lvds_options)

			return;

		index = sdvo_lvds_options->panel_type;

	}

	dvo_timing = find_section(bdb, BDB_SDVO_PANEL_DTDS);

	if (!dvo_timing)

		return;

	panel_fixed_mode = kzalloc(sizeof(*panel_fixed_mode), GFP_KERNEL);

	if (!panel_fixed_mode)

		return;

	fill_detail_timing_data(panel_fixed_mode, dvo_timing + index);

	dev_priv->sdvo_lvds_vbt_mode = panel_fixed_mode;

	DRM_DEBUG_KMS("Found SDVO panel mode in BIOS VBT tables:\n");

	drm_mode_debug_printmodeline(panel_fixed_mode);

}

static int intel_bios_ssc_frequency(struct drm_device *dev,

				    bool alternate)

{

	switch (INTEL_INFO(dev)->gen) {

	case 2:

		return alternate ? 66 : 48;

	case 3:

	case 4:

		return alternate ? 100 : 96;

	default:

		return alternate ? 100 : 120;

	}

}

static void

parse_general_features(struct drm_i915_private *dev_priv,

		       struct bdb_header *bdb)

{

	struct drm_device *dev = dev_priv->dev;

	struct bdb_general_features *general;

	general = find_section(bdb, BDB_GENERAL_FEATURES);

	if (general) {

		dev_priv->int_tv_support = general->int_tv_support;

		dev_priv->int_crt_support = general->int_crt_support;

		dev_priv->lvds_use_ssc = general->enable_ssc;

		dev_priv->lvds_ssc_freq =

			intel_bios_ssc_frequency(dev, general->ssc_freq);

		dev_priv->display_clock_mode = general->display_clock_mode;

		DRM_DEBUG_KMS("BDB_GENERAL_FEATURES int_tv_support %d int_crt_support %d lvds_use_ssc %d lvds_ssc_freq %d display_clock_mode %d\n",

			      dev_priv->int_tv_support,

			      dev_priv->int_crt_support,

			      dev_priv->lvds_use_ssc,

			      dev_priv->lvds_ssc_freq,

			      dev_priv->display_clock_mode);

	}

}

static void

parse_general_definitions(struct drm_i915_private *dev_priv,

			  struct bdb_header *bdb)

{

	struct bdb_general_definitions *general;

	general = find_section(bdb, BDB_GENERAL_DEFINITIONS);

	if (general) {

		u16 block_size = get_blocksize(general);

		if (block_size >= sizeof(*general)) {

			int bus_pin = general->crt_ddc_gmbus_pin;

			DRM_DEBUG_KMS("crt_ddc_bus_pin: %d\n", bus_pin);

			if (intel_gmbus_is_port_valid(bus_pin))

				dev_priv->crt_ddc_pin = bus_pin;

		} else {

			DRM_DEBUG_KMS("BDB_GD too small (%d). Invalid.\n",

				  block_size);

		}

	}

}

static void

parse_sdvo_device_mapping(struct drm_i915_private *dev_priv,

			  struct bdb_header *bdb)

{

	struct sdvo_device_mapping *p_mapping;

	struct bdb_general_definitions *p_defs;

	struct child_device_config *p_child;

	int i, child_device_num, count;

	u16	block_size;

	p_defs = find_section(bdb, BDB_GENERAL_DEFINITIONS);

	if (!p_defs) {

		DRM_DEBUG_KMS("No general definition block is found, unable to construct sdvo mapping.\n");

		return;

	}

	/* judge whether the size of child device meets the requirements.

	 * If the child device size obtained from general definition block

	 * is different with sizeof(struct child_device_config), skip the

	 * parsing of sdvo device info

	 */

	if (p_defs->child_dev_size != sizeof(*p_child)) {

		/* different child dev size . Ignore it */

		DRM_DEBUG_KMS("different child size is found. Invalid.\n");

		return;

	}

	/* get the block size of general definitions */

	block_size = get_blocksize(p_defs);

	/* get the number of child device */

	child_device_num = (block_size - sizeof(*p_defs)) /

				sizeof(*p_child);

	count = 0;

	for (i = 0; i < child_device_num; i++) {

		p_child = &(p_defs->devices[i]);

		if (!p_child->device_type) {

			/* skip the device block if device type is invalid */

			continue;

		}

		if (p_child->slave_addr != SLAVE_ADDR1 &&

			p_child->slave_addr != SLAVE_ADDR2) {

			/*

			 * If the slave address is neither 0x70 nor 0x72,

			 * it is not a SDVO device. Skip it.

			 */

			continue;

		}

		if (p_child->dvo_port != DEVICE_PORT_DVOB &&

			p_child->dvo_port != DEVICE_PORT_DVOC) {

			/* skip the incorrect SDVO port */

			DRM_DEBUG_KMS("Incorrect SDVO port. Skip it\n");

			continue;

		}

		DRM_DEBUG_KMS("the SDVO device with slave addr %2x is found on"

				" %s port\n",

				p_child->slave_addr,

				(p_child->dvo_port == DEVICE_PORT_DVOB) ?

					"SDVOB" : "SDVOC");

		p_mapping = &(dev_priv->sdvo_mappings[p_child->dvo_port - 1]);

		if (!p_mapping->initialized) {

			p_mapping->dvo_port = p_child->dvo_port;

			p_mapping->slave_addr = p_child->slave_addr;

			p_mapping->dvo_wiring = p_child->dvo_wiring;

			p_mapping->ddc_pin = p_child->ddc_pin;

			p_mapping->i2c_pin = p_child->i2c_pin;

			p_mapping->initialized = 1;

			DRM_DEBUG_KMS("SDVO device: dvo=%x, addr=%x, wiring=%d, ddc_pin=%d, i2c_pin=%d\n",

				      p_mapping->dvo_port,

				      p_mapping->slave_addr,

				      p_mapping->dvo_wiring,

				      p_mapping->ddc_pin,

				      p_mapping->i2c_pin);

		} else {

			DRM_DEBUG_KMS("Maybe one SDVO port is shared by "

					 "two SDVO device.\n");

		}

		if (p_child->slave2_addr) {

			/* Maybe this is a SDVO device with multiple inputs */

			/* And the mapping info is not added */

			DRM_DEBUG_KMS("there exists the slave2_addr. Maybe this"

				" is a SDVO device with multiple inputs.\n");

		}

		count++;

	}

	if (!count) {

		/* No SDVO device info is found */

		DRM_DEBUG_KMS("No SDVO device info is found in VBT\n");

	}

	return;

}

static void

parse_driver_features(struct drm_i915_private *dev_priv,

		       struct bdb_header *bdb)

{

	struct drm_device *dev = dev_priv->dev;

	struct bdb_driver_features *driver;

	driver = find_section(bdb, BDB_DRIVER_FEATURES);

	if (!driver)

		return;

	if (SUPPORTS_EDP(dev) &&

	    driver->lvds_config == BDB_DRIVER_FEATURE_EDP)

		dev_priv->edp.support = 1;

	if (driver->dual_frequency)

		dev_priv->render_reclock_avail = true;

}

static void

parse_edp(struct drm_i915_private *dev_priv, struct bdb_header *bdb)

{

	struct bdb_edp *edp;

	struct edp_power_seq *edp_pps;

	struct edp_link_params *edp_link_params;

	edp = find_section(bdb, BDB_EDP);

	if (!edp) {

		if (SUPPORTS_EDP(dev_priv->dev) && dev_priv->edp.support)

			DRM_DEBUG_KMS("No eDP BDB found but eDP panel supported.\n");

		return;

	}

	switch ((edp->color_depth >> (panel_type * 2)) & 3) {

	case EDP_18BPP:

		dev_priv->edp.bpp = 18;

		break;

	case EDP_24BPP:

		dev_priv->edp.bpp = 24;

		break;

	case EDP_30BPP:

		dev_priv->edp.bpp = 30;

		break;

	}

	/* Get the eDP sequencing and link info */

	edp_pps = &edp->power_seqs[panel_type];

	edp_link_params = &edp->link_params[panel_type];

	dev_priv->edp.pps = *edp_pps;

	dev_priv->edp.rate = edp_link_params->rate ? DP_LINK_BW_2_7 :

		DP_LINK_BW_1_62;

	switch (edp_link_params->lanes) {

	case 0:

		dev_priv->edp.lanes = 1;

		break;

	case 1:

		dev_priv->edp.lanes = 2;

		break;

	case 3:

	default:

		dev_priv->edp.lanes = 4;

		break;

	}

	switch (edp_link_params->preemphasis) {

	case 0:

		dev_priv->edp.preemphasis = DP_TRAIN_PRE_EMPHASIS_0;

		break;

	case 1:

		dev_priv->edp.preemphasis = DP_TRAIN_PRE_EMPHASIS_3_5;

		break;

	case 2:

		dev_priv->edp.preemphasis = DP_TRAIN_PRE_EMPHASIS_6;

		break;

	case 3:

		dev_priv->edp.preemphasis = DP_TRAIN_PRE_EMPHASIS_9_5;

		break;

	}

	switch (edp_link_params->vswing) {

	case 0:

		dev_priv->edp.vswing = DP_TRAIN_VOLTAGE_SWING_400;

		break;

	case 1:

		dev_priv->edp.vswing = DP_TRAIN_VOLTAGE_SWING_600;

		break;

	case 2:

		dev_priv->edp.vswing = DP_TRAIN_VOLTAGE_SWING_800;

		break;

	case 3:

		dev_priv->edp.vswing = DP_TRAIN_VOLTAGE_SWING_1200;

		break;

	}

}

static void

parse_device_mapping(struct drm_i915_private *dev_priv,

		       struct bdb_header *bdb)

{

	struct bdb_general_definitions *p_defs;

	struct child_device_config *p_child, *child_dev_ptr;

	int i, child_device_num, count;

	u16	block_size;

	p_defs = find_section(bdb, BDB_GENERAL_DEFINITIONS);

	if (!p_defs) {

		DRM_DEBUG_KMS("No general definition block is found, no devices defined.\n");

		return;

	}

	/* judge whether the size of child device meets the requirements.

	 * If the child device size obtained from general definition block

	 * is different with sizeof(struct child_device_config), skip the

	 * parsing of sdvo device info

	 */

	if (p_defs->child_dev_size != sizeof(*p_child)) {

		/* different child dev size . Ignore it */

		DRM_DEBUG_KMS("different child size is found. Invalid.\n");

		return;

	}

	/* get the block size of general definitions */

	block_size = get_blocksize(p_defs);

	/* get the number of child device */

	child_device_num = (block_size - sizeof(*p_defs)) /

				sizeof(*p_child);

	count = 0;

	/* get the number of child device that is present */

	for (i = 0; i < child_device_num; i++) {

		p_child = &(p_defs->devices[i]);

		if (!p_child->device_type) {

			/* skip the device block if device type is invalid */

			continue;

		}

		count++;

	}

	if (!count) {

		DRM_DEBUG_KMS("no child dev is parsed from VBT\n");

		return;

	}

	dev_priv->child_dev = kcalloc(count, sizeof(*p_child), GFP_KERNEL);

	if (!dev_priv->child_dev) {

		DRM_DEBUG_KMS("No memory space for child device\n");

		return;

	}

	dev_priv->child_dev_num = count;

	count = 0;

	for (i = 0; i < child_device_num; i++) {

		p_child = &(p_defs->devices[i]);

		if (!p_child->device_type) {

			/* skip the device block if device type is invalid */

			continue;

		}

		child_dev_ptr = dev_priv->child_dev + count;

		count++;

		memcpy((void *)child_dev_ptr, (void *)p_child,

					sizeof(*p_child));

	}

	return;

}

static void

init_vbt_defaults(struct drm_i915_private *dev_priv)

{

	struct drm_device *dev = dev_priv->dev;

	dev_priv->crt_ddc_pin = GMBUS_PORT_VGADDC;

	/* LFP panel data */

	dev_priv->lvds_dither = 1;

	dev_priv->lvds_vbt = 0;

	/* SDVO panel data */

	dev_priv->sdvo_lvds_vbt_mode = NULL;

	/* general features */

	dev_priv->int_tv_support = 1;

	dev_priv->int_crt_support = 1;

	/* Default to using SSC */

	dev_priv->lvds_use_ssc = 1;

	dev_priv->lvds_ssc_freq = intel_bios_ssc_frequency(dev, 1);

	DRM_DEBUG_KMS("Set default to SSC at %dMHz\n", dev_priv->lvds_ssc_freq);

}

/**

 * intel_parse_bios - find VBT and initialize settings from the BIOS

 * @dev: DRM device

 *

 * Loads the Video BIOS and checks that the VBT exists.  Sets scratch registers

 * to appropriate values.

 *

 * Returns 0 on success, nonzero on failure.

 */

int

intel_parse_bios(struct drm_device *dev)

{

	struct drm_i915_private *dev_priv = dev->dev_private;

	struct pci_dev *pdev = dev->pdev;

	struct bdb_header *bdb = NULL;

	u8 __iomem *bios = NULL;

	init_vbt_defaults(dev_priv);

	/* XXX Should this validation be moved to intel_opregion.c? */

	if (dev_priv->opregion.vbt) {

		struct vbt_header *vbt = dev_priv->opregion.vbt;

		if (memcmp(vbt->signature, "$VBT", 4) == 0) {

			DRM_DEBUG_KMS("Using VBT from OpRegion: %20s\n",

					 vbt->signature);

			bdb = (struct bdb_header *)((char *)vbt + vbt->bdb_offset);

		} else

			dev_priv->opregion.vbt = NULL;

	}

	if (bdb == NULL) {

		struct vbt_header *vbt = NULL;

		size_t size;

		int i;

		bios = pci_map_rom(pdev, &size);

		if (!bios)

			return -1;

		/* Scour memory looking for the VBT signature */

		for (i = 0; i + 4 < size; i++) {

			if (!memcmp(bios + i, "$VBT", 4)) {

				vbt = (struct vbt_header *)(bios + i);

				break;

			}

		}

		if (!vbt) {

			DRM_DEBUG_DRIVER("VBT signature missing\n");

			pci_unmap_rom(pdev, bios);

			return -1;

		}

		bdb = (struct bdb_header *)(bios + i + vbt->bdb_offset);

	}

	/* Grab useful general definitions */

	parse_general_features(dev_priv, bdb);

	parse_general_definitions(dev_priv, bdb);

	parse_lfp_panel_data(dev_priv, bdb);

	parse_sdvo_panel_data(dev_priv, bdb);

	parse_sdvo_device_mapping(dev_priv, bdb);

	parse_device_mapping(dev_priv, bdb);

	parse_driver_features(dev_priv, bdb);

	parse_edp(dev_priv, bdb);

	if (bios)

		pci_unmap_rom(pdev, bios);

	return 0;

}

/* Ensure that vital registers have been initialised, even if the BIOS

 * is absent or just failing to do its job.

 */

void intel_setup_bios(struct drm_device *dev)

{

	struct drm_i915_private *dev_priv = dev->dev_private;

	 /* Set the Panel Power On/Off timings if uninitialized. */

	if ((I915_READ(PP_ON_DELAYS) == 0) && (I915_READ(PP_OFF_DELAYS) == 0)) {

		/* Set T2 to 40ms and T5 to 200ms */

		I915_WRITE(PP_ON_DELAYS, 0x019007d0);

		/* Set T3 to 35ms and Tx to 200ms */

		I915_WRITE(PP_OFF_DELAYS, 0x015e07d0);

	}

}