src/include/edid.h

   1 /*
   2  * This file is part of the coreboot project.
   3  *
   4  * Copyright 2013 Google Inc.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; version 2 of the License.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  */
  15
  16 #ifndef EDID_H
  17 #define EDID_H
  18
  19 enum edid_modes {
  20         EDID_MODE_640x480_60Hz,
  21         EDID_MODE_720x480_60Hz,
  22         EDID_MODE_1280x720_60Hz,
  23         EDID_MODE_1920x1080_60Hz,
  24         NUM_KNOWN_MODES,
  25
  26         EDID_MODE_AUTO
  27 };
  28
  29 struct edid_mode {
  30         const char *name;
  31         unsigned int pixel_clock;
  32         int lvds_dual_channel;
  33         unsigned int refresh;
  34         unsigned int ha;
  35         unsigned int hbl;
  36         unsigned int hso;
  37         unsigned int hspw;
  38         unsigned int hborder;
  39         unsigned int va;
  40         unsigned int vbl;
  41         unsigned int vso;
  42         unsigned int vspw;
  43         unsigned int vborder;
  44         unsigned char phsync;
  45         unsigned char pvsync;
  46         unsigned int x_mm;
  47         unsigned int y_mm;
  48 };
  49
  50 /* structure for communicating EDID information from a raw EDID block to
  51  * higher level functions.
  52  * The size of the data types is not critical, so we leave them as
  53  * unsigned int. We can move more into into this struct as needed.
  54  */
  55
  56 #define EDID_ASCII_STRING_LENGTH 13
  57
  58 struct edid {
  59         /* These next three things used to all be called bpp.
  60          * Merriment ensued. The identifier
  61          * 'bpp' is herewith banished from our
  62          * Kingdom.
  63          */
  64         /* How many bits in the framebuffer per pixel.
  65          * Under all reasonable circumstances, it's 32.
  66          */
  67         unsigned int framebuffer_bits_per_pixel;
  68         /* On the panel, how many bits per color?
  69          * In almost all cases, it's 6 or 8.
  70          * The standard allows for much more!
  71          */
  72         unsigned int panel_bits_per_color;
  73         /* On the panel, how many bits per pixel.
  74          * On Planet Earth, there are three colors
  75          * per pixel, but this is convenient to have here
  76          * instead of having 3*panel_bits_per_color
  77          * all over the place.
  78          */
  79         unsigned int panel_bits_per_pixel;
  80         /* used to compute timing for graphics chips. */
  81         struct edid_mode mode;
  82         u8 mode_is_supported[NUM_KNOWN_MODES];
  83         unsigned int link_clock;
  84         /* 3 variables needed for coreboot framebuffer.
  85          * In most cases, they are the same as the ha
  86          * and va variables, but not always, as in the
  87          * case of a 1366 wide display.
  88          */
  89         u32 x_resolution;
  90         u32 y_resolution;
  91         u32 bytes_per_line;
  92
  93         int hdmi_monitor_detected;
  94         char ascii_string[EDID_ASCII_STRING_LENGTH + 1];
  95 };
  96
  97 enum edid_status {
  98         EDID_CONFORMANT,
  99         EDID_NOT_CONFORMANT,
 100         EDID_ABSENT,
 101 };
 102
 103 /* Defined in src/lib/edid.c */
 104 int decode_edid(unsigned char *edid, int size, struct edid *out);
 105 void edid_set_framebuffer_bits_per_pixel(struct edid *edid, int fb_bpp,
 106                                          int row_byte_alignment);
 107 void set_vbe_mode_info_valid(const struct edid *edid, uintptr_t fb_addr);
 108 int set_display_mode(struct edid *edid, enum edid_modes mode);
 109
 110 #endif /* EDID_H */