drivers/gpu/drm/i915/intel_bios.c

   1 /*
   2  * Copyright © 2006 Intel Corporation
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice (including the next
  12  * paragraph) shall be included in all copies or substantial portions of the
  13  * Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  20  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  21  * SOFTWARE.
  22  *
  23  * Authors:
  24  *    Eric Anholt <eric@anholt.net>
  25  *
  26  */
  27 #include "drmP.h"
  28 #include "drm.h"
  29 #include "i915_drm.h"
  30 #include "i915_drv.h"
  31 #include "intel_bios.h"
  32
  33
  34 static void *
  35 find_section(struct bdb_header *bdb, int section_id)
  36 {
  37         u8 *base = (u8 *)bdb;
  38         int index = 0;
  39         u16 total, current_size;
  40         u8 current_id;
  41
  42         /* skip to first section */
  43         index += bdb->header_size;
  44         total = bdb->bdb_size;
  45
  46         /* walk the sections looking for section_id */
  47         while (index < total) {
  48                 current_id = *(base + index);
  49                 index++;
  50                 current_size = *((u16 *)(base + index));
  51                 index += 2;
  52                 if (current_id == section_id)
  53                         return base + index;
  54                 index += current_size;
  55         }
  56
  57         return NULL;
  58 }
  59
  60 /* Try to find panel data */
  61 static void
  62 parse_panel_data(struct drm_i915_private *dev_priv, struct bdb_header *bdb)
  63 {
  64         struct bdb_lvds_options *lvds_options;
  65         struct bdb_lvds_lfp_data *lvds_lfp_data;
  66         struct bdb_lvds_lfp_data_entry *entry;
  67         struct lvds_dvo_timing *dvo_timing;
  68         struct drm_display_mode *panel_fixed_mode;
  69
  70         /* Defaults if we can't find VBT info */
  71         dev_priv->lvds_dither = 0;
  72         dev_priv->lvds_vbt = 0;
  73
  74         lvds_options = find_section(bdb, BDB_LVDS_OPTIONS);
  75         if (!lvds_options)
  76                 return;
  77
  78         dev_priv->lvds_dither = lvds_options->pixel_dither;
  79         if (lvds_options->panel_type == 0xff)
  80                 return;
  81
  82         lvds_lfp_data = find_section(bdb, BDB_LVDS_LFP_DATA);
  83         if (!lvds_lfp_data)
  84                 return;
  85
  86         dev_priv->lvds_vbt = 1;
  87
  88         entry = &lvds_lfp_data->data[lvds_options->panel_type];
  89         dvo_timing = &entry->dvo_timing;
  90
  91         panel_fixed_mode = drm_calloc(1, sizeof(*panel_fixed_mode),
  92                                       DRM_MEM_DRIVER);
  93
  94         panel_fixed_mode->hdisplay = (dvo_timing->hactive_hi << 8) |
  95                 dvo_timing->hactive_lo;
  96         panel_fixed_mode->hsync_start = panel_fixed_mode->hdisplay +
  97                 ((dvo_timing->hsync_off_hi << 8) | dvo_timing->hsync_off_lo);
  98         panel_fixed_mode->hsync_end = panel_fixed_mode->hsync_start +
  99                 dvo_timing->hsync_pulse_width;
 100         panel_fixed_mode->htotal = panel_fixed_mode->hdisplay +
 101                 ((dvo_timing->hblank_hi << 8) | dvo_timing->hblank_lo);
 102
 103         panel_fixed_mode->vdisplay = (dvo_timing->vactive_hi << 8) |
 104                 dvo_timing->vactive_lo;
 105         panel_fixed_mode->vsync_start = panel_fixed_mode->vdisplay +
 106                 dvo_timing->vsync_off;
 107         panel_fixed_mode->vsync_end = panel_fixed_mode->vsync_start +
 108                 dvo_timing->vsync_pulse_width;
 109         panel_fixed_mode->vtotal = panel_fixed_mode->vdisplay +
 110                 ((dvo_timing->vblank_hi << 8) | dvo_timing->vblank_lo);
 111         panel_fixed_mode->clock = dvo_timing->clock * 10;
 112         panel_fixed_mode->type = DRM_MODE_TYPE_PREFERRED;
 113
 114         drm_mode_set_name(panel_fixed_mode);
 115
 116         dev_priv->vbt_mode = panel_fixed_mode;
 117
 118         DRM_DEBUG("Found panel mode in BIOS VBT tables:\n");
 119         drm_mode_debug_printmodeline(panel_fixed_mode);
 120
 121         return;
 122 }
 123
 124 static void
 125 parse_general_features(struct drm_i915_private *dev_priv,
 126                        struct bdb_header *bdb)
 127 {
 128         struct bdb_general_features *general;
 129
 130         /* Set sensible defaults in case we can't find the general block */
 131         dev_priv->int_tv_support = 1;
 132         dev_priv->int_crt_support = 1;
 133
 134         general = find_section(bdb, BDB_GENERAL_FEATURES);
 135         if (general) {
 136                 dev_priv->int_tv_support = general->int_tv_support;
 137                 dev_priv->int_crt_support = general->int_crt_support;
 138         }
 139 }
 140
 141 /**
 142  * intel_init_bios - initialize VBIOS settings & find VBT
 143  * @dev: DRM device
 144  *
 145  * Loads the Video BIOS and checks that the VBT exists.  Sets scratch registers
 146  * to appropriate values.
 147  *
 148  * VBT existence is a sanity check that is relied on by other i830_bios.c code.
 149  * Note that it would be better to use a BIOS call to get the VBT, as BIOSes may
 150  * feed an updated VBT back through that, compared to what we'll fetch using
 151  * this method of groping around in the BIOS data.
 152  *
 153  * Returns 0 on success, nonzero on failure.
 154  */
 155 bool
 156 intel_init_bios(struct drm_device *dev)
 157 {
 158         struct drm_i915_private *dev_priv = dev->dev_private;
 159         struct pci_dev *pdev = dev->pdev;
 160         struct vbt_header *vbt = NULL;
 161         struct bdb_header *bdb;
 162         u8 __iomem *bios;
 163         size_t size;
 164         int i;
 165
 166         bios = pci_map_rom(pdev, &size);
 167         if (!bios)
 168                 return -1;
 169
 170         /* Scour memory looking for the VBT signature */
 171         for (i = 0; i + 4 < size; i++) {
 172                 if (!memcmp(bios + i, "$VBT", 4)) {
 173                         vbt = (struct vbt_header *)(bios + i);
 174                         break;
 175                 }
 176         }
 177
 178         if (!vbt) {
 179                 DRM_ERROR("VBT signature missing\n");
 180                 pci_unmap_rom(pdev, bios);
 181                 return -1;
 182         }
 183
 184         bdb = (struct bdb_header *)(bios + i + vbt->bdb_offset);
 185
 186         /* Grab useful general definitions */
 187         parse_general_features(dev_priv, bdb);
 188         parse_panel_data(dev_priv, bdb);
 189
 190         pci_unmap_rom(pdev, bios);
 191
 192         return 0;
 193 }