u-boot/common/edid.c
Simon Glass 00cf1167bb edid: Add a function to read detailed monitor timings
For digital displays (such as EDP LCDs) we would like to read the EDID
information and use that to set display timings. Provide a function to do
this.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Tom Warren <twarren@nvidia.com>
2015-05-13 09:24:10 -07:00

408 lines
12 KiB
C

/*
* Copyright (c) 2012 The Chromium OS Authors.
*
* (C) Copyright 2010
* Petr Stetiar <ynezz@true.cz>
*
* SPDX-License-Identifier: GPL-2.0+
*
* Contains stolen code from ddcprobe project which is:
* Copyright (C) Nalin Dahyabhai <bigfun@pobox.com>
*/
#include <common.h>
#include <edid.h>
#include <errno.h>
#include <fdtdec.h>
#include <linux/ctype.h>
#include <linux/string.h>
int edid_check_info(struct edid1_info *edid_info)
{
if ((edid_info == NULL) || (edid_info->version == 0))
return -1;
if (memcmp(edid_info->header, "\x0\xff\xff\xff\xff\xff\xff\x0", 8))
return -1;
if (edid_info->version == 0xff && edid_info->revision == 0xff)
return -1;
return 0;
}
int edid_check_checksum(u8 *edid_block)
{
u8 checksum = 0;
int i;
for (i = 0; i < 128; i++)
checksum += edid_block[i];
return (checksum == 0) ? 0 : -EINVAL;
}
int edid_get_ranges(struct edid1_info *edid, unsigned int *hmin,
unsigned int *hmax, unsigned int *vmin,
unsigned int *vmax)
{
int i;
struct edid_monitor_descriptor *monitor;
*hmin = *hmax = *vmin = *vmax = 0;
if (edid_check_info(edid))
return -1;
for (i = 0; i < ARRAY_SIZE(edid->monitor_details.descriptor); i++) {
monitor = &edid->monitor_details.descriptor[i];
if (monitor->type == EDID_MONITOR_DESCRIPTOR_RANGE) {
*hmin = monitor->data.range_data.horizontal_min;
*hmax = monitor->data.range_data.horizontal_max;
*vmin = monitor->data.range_data.vertical_min;
*vmax = monitor->data.range_data.vertical_max;
return 0;
}
}
return -1;
}
/* Set all parts of a timing entry to the same value */
static void set_entry(struct timing_entry *entry, u32 value)
{
entry->min = value;
entry->typ = value;
entry->max = value;
}
/**
* decode_timing() - Decoding an 18-byte detailed timing record
*
* @buf: Pointer to EDID detailed timing record
* @timing: Place to put timing
*/
static void decode_timing(u8 *buf, struct display_timing *timing)
{
uint x_mm, y_mm;
unsigned int ha, hbl, hso, hspw, hborder;
unsigned int va, vbl, vso, vspw, vborder;
/* Edid contains pixel clock in terms of 10KHz */
set_entry(&timing->pixelclock, (buf[0] + (buf[1] << 8)) * 10000);
x_mm = (buf[12] + ((buf[14] & 0xf0) << 4));
y_mm = (buf[13] + ((buf[14] & 0x0f) << 8));
ha = (buf[2] + ((buf[4] & 0xf0) << 4));
hbl = (buf[3] + ((buf[4] & 0x0f) << 8));
hso = (buf[8] + ((buf[11] & 0xc0) << 2));
hspw = (buf[9] + ((buf[11] & 0x30) << 4));
hborder = buf[15];
va = (buf[5] + ((buf[7] & 0xf0) << 4));
vbl = (buf[6] + ((buf[7] & 0x0f) << 8));
vso = ((buf[10] >> 4) + ((buf[11] & 0x0c) << 2));
vspw = ((buf[10] & 0x0f) + ((buf[11] & 0x03) << 4));
vborder = buf[16];
set_entry(&timing->hactive, ha);
set_entry(&timing->hfront_porch, hso);
set_entry(&timing->hback_porch, hbl - hso - hspw);
set_entry(&timing->hsync_len, hspw);
set_entry(&timing->vactive, va);
set_entry(&timing->vfront_porch, vso);
set_entry(&timing->vback_porch, vbl - vso - vspw);
set_entry(&timing->vsync_len, vspw);
debug("Detailed mode clock %u Hz, %d mm x %d mm\n"
" %04x %04x %04x %04x hborder %x\n"
" %04x %04x %04x %04x vborder %x\n",
timing->pixelclock.typ,
x_mm, y_mm,
ha, ha + hso, ha + hso + hspw,
ha + hbl, hborder,
va, va + vso, va + vso + vspw,
va + vbl, vborder);
}
int edid_get_timing(u8 *buf, int buf_size, struct display_timing *timing,
int *panel_bits_per_colourp)
{
struct edid1_info *edid = (struct edid1_info *)buf;
bool timing_done;
int i;
if (buf_size < sizeof(*edid) || edid_check_info(edid)) {
debug("%s: Invalid buffer\n", __func__);
return -EINVAL;
}
if (!EDID1_INFO_FEATURE_PREFERRED_TIMING_MODE(*edid)) {
debug("%s: No preferred timing\n", __func__);
return -ENOENT;
}
/* Look for detailed timing */
timing_done = false;
for (i = 0; i < 4; i++) {
struct edid_monitor_descriptor *desc;
desc = &edid->monitor_details.descriptor[i];
if (desc->zero_flag_1 != 0) {
decode_timing((u8 *)desc, timing);
timing_done = true;
break;
}
}
if (!timing_done)
return -EINVAL;
if (!EDID1_INFO_VIDEO_INPUT_DIGITAL(*edid)) {
debug("%s: Not a digital display\n", __func__);
return -ENOSYS;
}
if (edid->version != 1 || edid->revision < 4) {
debug("%s: EDID version %d.%d does not have required info\n",
__func__, edid->version, edid->revision);
*panel_bits_per_colourp = -1;
} else {
*panel_bits_per_colourp =
((edid->video_input_definition & 0x70) >> 3) + 4;
}
return 0;
}
/**
* Snip the tailing whitespace/return of a string.
*
* @param string The string to be snipped
* @return the snipped string
*/
static char *snip(char *string)
{
char *s;
/*
* This is always a 13 character buffer
* and it's not always terminated.
*/
string[12] = '\0';
s = &string[strlen(string) - 1];
while (s >= string && (isspace(*s) || *s == '\n' || *s == '\r' ||
*s == '\0'))
*(s--) = '\0';
return string;
}
/**
* Print an EDID monitor descriptor block
*
* @param monitor The EDID monitor descriptor block
* @have_timing Modifies to 1 if the desciptor contains timing info
*/
static void edid_print_dtd(struct edid_monitor_descriptor *monitor,
unsigned int *have_timing)
{
unsigned char *bytes = (unsigned char *)monitor;
struct edid_detailed_timing *timing =
(struct edid_detailed_timing *)monitor;
if (bytes[0] == 0 && bytes[1] == 0) {
if (monitor->type == EDID_MONITOR_DESCRIPTOR_SERIAL)
printf("Monitor serial number: %s\n",
snip(monitor->data.string));
else if (monitor->type == EDID_MONITOR_DESCRIPTOR_ASCII)
printf("Monitor ID: %s\n",
snip(monitor->data.string));
else if (monitor->type == EDID_MONITOR_DESCRIPTOR_NAME)
printf("Monitor name: %s\n",
snip(monitor->data.string));
else if (monitor->type == EDID_MONITOR_DESCRIPTOR_RANGE)
printf("Monitor range limits, horizontal sync: "
"%d-%d kHz, vertical refresh: "
"%d-%d Hz, max pixel clock: "
"%d MHz\n",
monitor->data.range_data.horizontal_min,
monitor->data.range_data.horizontal_max,
monitor->data.range_data.vertical_min,
monitor->data.range_data.vertical_max,
monitor->data.range_data.pixel_clock_max * 10);
} else {
uint32_t pixclock, h_active, h_blanking, v_active, v_blanking;
uint32_t h_total, v_total, vfreq;
pixclock = EDID_DETAILED_TIMING_PIXEL_CLOCK(*timing);
h_active = EDID_DETAILED_TIMING_HORIZONTAL_ACTIVE(*timing);
h_blanking = EDID_DETAILED_TIMING_HORIZONTAL_BLANKING(*timing);
v_active = EDID_DETAILED_TIMING_VERTICAL_ACTIVE(*timing);
v_blanking = EDID_DETAILED_TIMING_VERTICAL_BLANKING(*timing);
h_total = h_active + h_blanking;
v_total = v_active + v_blanking;
if (v_total * h_total)
vfreq = pixclock / (v_total * h_total);
else
vfreq = 1; /* Error case */
printf("\t%dx%d\%c\t%d Hz (detailed)\n", h_active,
v_active, h_active > 1000 ? ' ' : '\t', vfreq);
*have_timing = 1;
}
}
/**
* Get the manufacturer name from an EDID info.
*
* @param edid_info The EDID info to be printed
* @param name Returns the string of the manufacturer name
*/
static void edid_get_manufacturer_name(struct edid1_info *edid, char *name)
{
name[0] = EDID1_INFO_MANUFACTURER_NAME_CHAR1(*edid) + 'A' - 1;
name[1] = EDID1_INFO_MANUFACTURER_NAME_CHAR2(*edid) + 'A' - 1;
name[2] = EDID1_INFO_MANUFACTURER_NAME_CHAR3(*edid) + 'A' - 1;
name[3] = '\0';
}
void edid_print_info(struct edid1_info *edid_info)
{
int i;
char manufacturer[4];
unsigned int have_timing = 0;
uint32_t serial_number;
if (edid_check_info(edid_info)) {
printf("Not a valid EDID\n");
return;
}
printf("EDID version: %d.%d\n",
edid_info->version, edid_info->revision);
printf("Product ID code: %04x\n", EDID1_INFO_PRODUCT_CODE(*edid_info));
edid_get_manufacturer_name(edid_info, manufacturer);
printf("Manufacturer: %s\n", manufacturer);
serial_number = EDID1_INFO_SERIAL_NUMBER(*edid_info);
if (serial_number != 0xffffffff) {
if (strcmp(manufacturer, "MAG") == 0)
serial_number -= 0x7000000;
if (strcmp(manufacturer, "OQI") == 0)
serial_number -= 456150000;
if (strcmp(manufacturer, "VSC") == 0)
serial_number -= 640000000;
}
printf("Serial number: %08x\n", serial_number);
printf("Manufactured in week: %d year: %d\n",
edid_info->week, edid_info->year + 1990);
printf("Video input definition: %svoltage level %d%s%s%s%s%s\n",
EDID1_INFO_VIDEO_INPUT_DIGITAL(*edid_info) ?
"digital signal, " : "analog signal, ",
EDID1_INFO_VIDEO_INPUT_VOLTAGE_LEVEL(*edid_info),
EDID1_INFO_VIDEO_INPUT_BLANK_TO_BLACK(*edid_info) ?
", blank to black" : "",
EDID1_INFO_VIDEO_INPUT_SEPARATE_SYNC(*edid_info) ?
", separate sync" : "",
EDID1_INFO_VIDEO_INPUT_COMPOSITE_SYNC(*edid_info) ?
", composite sync" : "",
EDID1_INFO_VIDEO_INPUT_SYNC_ON_GREEN(*edid_info) ?
", sync on green" : "",
EDID1_INFO_VIDEO_INPUT_SERRATION_V(*edid_info) ?
", serration v" : "");
printf("Monitor is %s\n",
EDID1_INFO_FEATURE_RGB(*edid_info) ? "RGB" : "non-RGB");
printf("Maximum visible display size: %d cm x %d cm\n",
edid_info->max_size_horizontal,
edid_info->max_size_vertical);
printf("Power management features: %s%s, %s%s, %s%s\n",
EDID1_INFO_FEATURE_ACTIVE_OFF(*edid_info) ?
"" : "no ", "active off",
EDID1_INFO_FEATURE_SUSPEND(*edid_info) ? "" : "no ", "suspend",
EDID1_INFO_FEATURE_STANDBY(*edid_info) ? "" : "no ", "standby");
printf("Estabilished timings:\n");
if (EDID1_INFO_ESTABLISHED_TIMING_720X400_70(*edid_info))
printf("\t720x400\t\t70 Hz (VGA 640x400, IBM)\n");
if (EDID1_INFO_ESTABLISHED_TIMING_720X400_88(*edid_info))
printf("\t720x400\t\t88 Hz (XGA2)\n");
if (EDID1_INFO_ESTABLISHED_TIMING_640X480_60(*edid_info))
printf("\t640x480\t\t60 Hz (VGA)\n");
if (EDID1_INFO_ESTABLISHED_TIMING_640X480_67(*edid_info))
printf("\t640x480\t\t67 Hz (Mac II, Apple)\n");
if (EDID1_INFO_ESTABLISHED_TIMING_640X480_72(*edid_info))
printf("\t640x480\t\t72 Hz (VESA)\n");
if (EDID1_INFO_ESTABLISHED_TIMING_640X480_75(*edid_info))
printf("\t640x480\t\t75 Hz (VESA)\n");
if (EDID1_INFO_ESTABLISHED_TIMING_800X600_56(*edid_info))
printf("\t800x600\t\t56 Hz (VESA)\n");
if (EDID1_INFO_ESTABLISHED_TIMING_800X600_60(*edid_info))
printf("\t800x600\t\t60 Hz (VESA)\n");
if (EDID1_INFO_ESTABLISHED_TIMING_800X600_72(*edid_info))
printf("\t800x600\t\t72 Hz (VESA)\n");
if (EDID1_INFO_ESTABLISHED_TIMING_800X600_75(*edid_info))
printf("\t800x600\t\t75 Hz (VESA)\n");
if (EDID1_INFO_ESTABLISHED_TIMING_832X624_75(*edid_info))
printf("\t832x624\t\t75 Hz (Mac II)\n");
if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_87I(*edid_info))
printf("\t1024x768\t87 Hz Interlaced (8514A)\n");
if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_60(*edid_info))
printf("\t1024x768\t60 Hz (VESA)\n");
if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_70(*edid_info))
printf("\t1024x768\t70 Hz (VESA)\n");
if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_75(*edid_info))
printf("\t1024x768\t75 Hz (VESA)\n");
if (EDID1_INFO_ESTABLISHED_TIMING_1280X1024_75(*edid_info))
printf("\t1280x1024\t75 (VESA)\n");
if (EDID1_INFO_ESTABLISHED_TIMING_1152X870_75(*edid_info))
printf("\t1152x870\t75 (Mac II)\n");
/* Standard timings. */
printf("Standard timings:\n");
for (i = 0; i < ARRAY_SIZE(edid_info->standard_timings); i++) {
unsigned int aspect = 10000;
unsigned int x, y;
unsigned char xres, vfreq;
xres = EDID1_INFO_STANDARD_TIMING_XRESOLUTION(*edid_info, i);
vfreq = EDID1_INFO_STANDARD_TIMING_VFREQ(*edid_info, i);
if ((xres != vfreq) ||
((xres != 0) && (xres != 1)) ||
((vfreq != 0) && (vfreq != 1))) {
switch (EDID1_INFO_STANDARD_TIMING_ASPECT(*edid_info,
i)) {
case ASPECT_625:
aspect = 6250;
break;
case ASPECT_75:
aspect = 7500;
break;
case ASPECT_8:
aspect = 8000;
break;
case ASPECT_5625:
aspect = 5625;
break;
}
x = (xres + 31) * 8;
y = x * aspect / 10000;
printf("\t%dx%d%c\t%d Hz\n", x, y,
x > 1000 ? ' ' : '\t', (vfreq & 0x3f) + 60);
have_timing = 1;
}
}
/* Detailed timing information. */
for (i = 0; i < ARRAY_SIZE(edid_info->monitor_details.descriptor);
i++) {
edid_print_dtd(&edid_info->monitor_details.descriptor[i],
&have_timing);
}
if (!have_timing)
printf("\tNone\n");
}