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author | Hans de Goede <hdegoede@redhat.com> | 2014-12-28 09:13:21 +0100 |
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committer | Hans de Goede <hdegoede@redhat.com> | 2015-01-14 14:56:39 +0100 |
commit | 7fad8a98020a0ead8b7bdd5f6b5eaf49b91658b5 (patch) | |
tree | 9be5434cca311768081bbbf62b53c3aceae6ae85 /doc/README.video | |
parent | d9786d23808fcbc5dd3bd3913b036d42dd48653f (diff) | |
download | u-boot-7fad8a98020a0ead8b7bdd5f6b5eaf49b91658b5.zip u-boot-7fad8a98020a0ead8b7bdd5f6b5eaf49b91658b5.tar.gz u-boot-7fad8a98020a0ead8b7bdd5f6b5eaf49b91658b5.tar.bz2 |
sunxi: video: Add a hpd_delay parameter to configure hpd delay
In some extreme cases it may be necessary to wait 1.5 seconds or more for a hpd
signal to show up (and be able to read edid info), but we do not want to
penalize all headless boots with an extra second boot delay, so add a hpd_delay
parameter which can be set through the video-mode env. variable.
While at it raise the default from 300ms to 500ms as 300 may very well be too
low in many cases.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Ian Campbell <ijc@hellion.org.uk>
Diffstat (limited to 'doc/README.video')
-rw-r--r-- | doc/README.video | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/doc/README.video b/doc/README.video index 2c55d6a..d0a3ad6 100644 --- a/doc/README.video +++ b/doc/README.video @@ -53,6 +53,12 @@ The sunxi u-boot driver supports the following video-mode options: 1: Enabled. Fallback to the lcd / vga / none in that order (if available) Defaults to hpd=1. +- hpd_delay=<int> - How long to wait for the hdmi HPD signal in milliseconds + When the monitor and the board power up at the same time, it may take some + time for the monitor to assert the HPD signal. This configures how long to + wait for the HPD signal before assuming no cable is connected. + Defaults to hpd_delay=500. + - edid=[0|1] - Enable use of DDC + EDID to get monitor info 0: Disabled. 1: Enabled. If valid EDID info was read from the monitor the EDID info will @@ -61,4 +67,4 @@ The sunxi u-boot driver supports the following video-mode options: For example to always use the hdmi connector, even if no cable is inserted, using edid info when available and otherwise initalizing it at 1024x768@60Hz, -use: video-mode=sunxi:1024x768-24@60,monitor=dvi,hpd=0,edid=1 . +use: "setenv video-mode sunxi:1024x768-24@60,monitor=dvi,hpd=0,edid=1". |