Hi,
On 11/25/2014 09:53 AM, Ian Campbell wrote:
On Sun, 2014-11-23 at 17:12 +0100, Hans de Goede wrote:
Add the following extra modes:
1280x720@50
1920x1080@60
1920x1200@60
And allow selecting them by setting (and then saving and rebooting) a
hdmi_mode env variable to the name of the mode.
Is there any u-boot side standard for the naming/format of such a
variable? (adding Anatolij for input too).
I see a bunch of platforms apparently using video= (just from a grep on
includes/configs for video=), likewise videomode= which is also
described in README but doesn't look to cover the sort of things wanted
here.
Ok, so I've been thinking a bit about this, I plan to also support
lcd support one of these days, I was thinking using lcd_mode= for that,
but probably having one mechanism is better.
So here is what I've been thinking, we add support for a video=
environment variable, which is build up like this:
video=[auto:][<output>:]<modename>
So one could do:
video=auto:dvi:1280x720@50
Which would mean: auto-detect, if that fails then configure
dvi out on 1280x720@50
This also works well with code I'm currently working on, our current hdmi
support is actually dvi out, as we're not sending a hdmi avi info frame.
For some displays this is a problem, as they only work with proper hdmi data,
so currently I'm working on making the sunxi display code (optionally) send
proper hdmi data. Note we cannot always do this, as dvi monitors cannot deal
with it. So people would be able to do:
video=hdmi:1920x1080@60
To force hdmi output format, or:
video=dvi:1920x1080@60
To force dvi output.
And for lcd people could use:
video=lcd:800x480@50
Or:
video=auto:lcd:800x480@50
Which would first try hdmi (see if a cable is attached) + edid,
and if that does not work light up the lcd instead.
The exact behavior of auto would be board specific, but the basic
video= parsing could live in generic code...
Is there note some centralise db of struct db_videomode we can use?
Seems like not, oh well.
And use a shared mode database, and actually fill a fb_videomode struct
for us.
Does that sound like a plan ?
Anatolij, what do you think about this ?
Regards,
Hans
_______________________________________________
U-Boot mailing list
U-Boot@lists.denx.de
http://lists.denx.de/mailman/listinfo/u-boot
