|  | /* | 
|  | * 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 <eric@anholt.net> | 
|  | * | 
|  | */ | 
|  | #include "drmP.h" | 
|  | #include "drm.h" | 
|  | #include "i915_drm.h" | 
|  | #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, | 
|  | 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); | 
|  | } | 
|  |  | 
|  | /* Try to find integrated panel data */ | 
|  | static void | 
|  | parse_lfp_panel_data(struct drm_i915_private *dev_priv, | 
|  | struct bdb_header *bdb) | 
|  | { | 
|  | struct bdb_lvds_options *lvds_options; | 
|  | struct bdb_lvds_lfp_data *lvds_lfp_data; | 
|  | struct bdb_lvds_lfp_data_ptrs *lvds_lfp_data_ptrs; | 
|  | struct bdb_lvds_lfp_data_entry *entry; | 
|  | struct lvds_dvo_timing *dvo_timing; | 
|  | struct drm_display_mode *panel_fixed_mode; | 
|  | int lfp_data_size, dvo_timing_offset; | 
|  | int i, temp_downclock; | 
|  | struct drm_display_mode *temp_mode; | 
|  |  | 
|  | /* Defaults if we can't find VBT info */ | 
|  | dev_priv->lvds_dither = 0; | 
|  | dev_priv->lvds_vbt = 0; | 
|  |  | 
|  | 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; | 
|  |  | 
|  | lfp_data_size = lvds_lfp_data_ptrs->ptr[1].dvo_timing_offset - | 
|  | lvds_lfp_data_ptrs->ptr[0].dvo_timing_offset; | 
|  | entry = (struct bdb_lvds_lfp_data_entry *) | 
|  | ((uint8_t *)lvds_lfp_data->data + (lfp_data_size * | 
|  | lvds_options->panel_type)); | 
|  | dvo_timing_offset = lvds_lfp_data_ptrs->ptr[0].dvo_timing_offset - | 
|  | lvds_lfp_data_ptrs->ptr[0].fp_timing_offset; | 
|  |  | 
|  | /* | 
|  | * 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 | 
|  | */ | 
|  | dvo_timing = (struct lvds_dvo_timing *) | 
|  | ((unsigned char *)entry + dvo_timing_offset); | 
|  |  | 
|  | panel_fixed_mode = kzalloc(sizeof(*panel_fixed_mode), GFP_KERNEL); | 
|  |  | 
|  | fill_detail_timing_data(panel_fixed_mode, 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); | 
|  |  | 
|  | temp_mode = kzalloc(sizeof(*temp_mode), GFP_KERNEL); | 
|  | temp_downclock = panel_fixed_mode->clock; | 
|  | /* | 
|  | * enumerate the LVDS panel timing info entry in VBT to check whether | 
|  | * the LVDS downclock is found. | 
|  | */ | 
|  | for (i = 0; i < 16; i++) { | 
|  | entry = (struct bdb_lvds_lfp_data_entry *) | 
|  | ((uint8_t *)lvds_lfp_data->data + (lfp_data_size * i)); | 
|  | dvo_timing = (struct lvds_dvo_timing *) | 
|  | ((unsigned char *)entry + dvo_timing_offset); | 
|  |  | 
|  | fill_detail_timing_data(temp_mode, dvo_timing); | 
|  |  | 
|  | if (temp_mode->hdisplay == panel_fixed_mode->hdisplay && | 
|  | temp_mode->hsync_start == panel_fixed_mode->hsync_start && | 
|  | temp_mode->hsync_end == panel_fixed_mode->hsync_end && | 
|  | temp_mode->htotal == panel_fixed_mode->htotal && | 
|  | temp_mode->vdisplay == panel_fixed_mode->vdisplay && | 
|  | temp_mode->vsync_start == panel_fixed_mode->vsync_start && | 
|  | temp_mode->vsync_end == panel_fixed_mode->vsync_end && | 
|  | temp_mode->vtotal == panel_fixed_mode->vtotal && | 
|  | temp_mode->clock < temp_downclock) { | 
|  | /* | 
|  | * downclock is already found. But we expect | 
|  | * to find the lower downclock. | 
|  | */ | 
|  | temp_downclock = temp_mode->clock; | 
|  | } | 
|  | /* clear it to zero */ | 
|  | memset(temp_mode, 0, sizeof(*temp_mode)); | 
|  | } | 
|  | kfree(temp_mode); | 
|  | if (temp_downclock < panel_fixed_mode->clock && | 
|  | i915_lvds_downclock) { | 
|  | dev_priv->lvds_downclock_avail = 1; | 
|  | dev_priv->lvds_downclock = temp_downclock; | 
|  | DRM_DEBUG_KMS("LVDS downclock is found in VBT. ", | 
|  | "Normal Clock %dKHz, downclock %dKHz\n", | 
|  | temp_downclock, panel_fixed_mode->clock); | 
|  | } | 
|  | return; | 
|  | } | 
|  |  | 
|  | /* Try to find sdvo panel data */ | 
|  | static void | 
|  | parse_sdvo_panel_data(struct drm_i915_private *dev_priv, | 
|  | struct bdb_header *bdb) | 
|  | { | 
|  | struct bdb_sdvo_lvds_options *sdvo_lvds_options; | 
|  | struct lvds_dvo_timing *dvo_timing; | 
|  | struct drm_display_mode *panel_fixed_mode; | 
|  |  | 
|  | dev_priv->sdvo_lvds_vbt_mode = NULL; | 
|  |  | 
|  | sdvo_lvds_options = find_section(bdb, BDB_SDVO_LVDS_OPTIONS); | 
|  | if (!sdvo_lvds_options) | 
|  | return; | 
|  |  | 
|  | 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 + sdvo_lvds_options->panel_type); | 
|  |  | 
|  | dev_priv->sdvo_lvds_vbt_mode = panel_fixed_mode; | 
|  |  | 
|  | return; | 
|  | } | 
|  |  | 
|  | 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; | 
|  |  | 
|  | /* Set sensible defaults in case we can't find the general block */ | 
|  | dev_priv->int_tv_support = 1; | 
|  | dev_priv->int_crt_support = 1; | 
|  |  | 
|  | 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; | 
|  |  | 
|  | if (dev_priv->lvds_use_ssc) { | 
|  | if (IS_I85X(dev_priv->dev)) | 
|  | dev_priv->lvds_ssc_freq = | 
|  | general->ssc_freq ? 66 : 48; | 
|  | else if (IS_IRONLAKE(dev_priv->dev) || IS_GEN6(dev)) | 
|  | dev_priv->lvds_ssc_freq = | 
|  | general->ssc_freq ? 100 : 120; | 
|  | else | 
|  | dev_priv->lvds_ssc_freq = | 
|  | general->ssc_freq ? 100 : 96; | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | static void | 
|  | parse_general_definitions(struct drm_i915_private *dev_priv, | 
|  | struct bdb_header *bdb) | 
|  | { | 
|  | struct bdb_general_definitions *general; | 
|  | const int crt_bus_map_table[] = { | 
|  | GPIOB, | 
|  | GPIOA, | 
|  | GPIOC, | 
|  | GPIOD, | 
|  | GPIOE, | 
|  | GPIOF, | 
|  | }; | 
|  |  | 
|  | 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 ((bus_pin >= 1) && (bus_pin <= 6)) { | 
|  | dev_priv->crt_ddc_bus = | 
|  | crt_bus_map_table[bus_pin-1]; | 
|  | } | 
|  | } 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\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->initialized = 1; | 
|  | } 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 (driver && SUPPORTS_EDP(dev) && | 
|  | driver->lvds_config == BDB_DRIVER_FEATURE_EDP) { | 
|  | dev_priv->edp_support = 1; | 
|  | } else { | 
|  | dev_priv->edp_support = 0; | 
|  | } | 
|  |  | 
|  | if (driver && 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; | 
|  |  | 
|  | 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, assume 18bpp panel color " | 
|  | "depth.\n"); | 
|  | dev_priv->edp_bpp = 18; | 
|  | } | 
|  | 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; | 
|  | } | 
|  | } | 
|  |  | 
|  | 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\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 = kzalloc(sizeof(*p_child) * count, 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; | 
|  | } | 
|  | /** | 
|  | * intel_init_bios - initialize VBIOS settings & find VBT | 
|  | * @dev: DRM device | 
|  | * | 
|  | * Loads the Video BIOS and checks that the VBT exists.  Sets scratch registers | 
|  | * to appropriate values. | 
|  | * | 
|  | * VBT existence is a sanity check that is relied on by other i830_bios.c code. | 
|  | * Note that it would be better to use a BIOS call to get the VBT, as BIOSes may | 
|  | * feed an updated VBT back through that, compared to what we'll fetch using | 
|  | * this method of groping around in the BIOS data. | 
|  | * | 
|  | * Returns 0 on success, nonzero on failure. | 
|  | */ | 
|  | bool | 
|  | intel_init_bios(struct drm_device *dev) | 
|  | { | 
|  | struct drm_i915_private *dev_priv = dev->dev_private; | 
|  | struct pci_dev *pdev = dev->pdev; | 
|  | struct vbt_header *vbt = NULL; | 
|  | struct bdb_header *bdb; | 
|  | u8 __iomem *bios; | 
|  | 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_ERROR("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); | 
|  |  | 
|  | pci_unmap_rom(pdev, bios); | 
|  |  | 
|  | return 0; | 
|  | } |