From 7fad8a98020a0ead8b7bdd5f6b5eaf49b91658b5 Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Sun, 28 Dec 2014 09:13:21 +0100 Subject: 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 Acked-by: Ian Campbell --- doc/README.video | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) (limited to 'doc/README.video') 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= - 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". -- cgit v1.1