hi tornado
I have installed fbturbo driver follow this posts https://archlinuxarm.org/forum/viewtopic.php?f=33&t=5979.
It did improve chromium performance a lot.I also found that it's used in Raspbian Jessie.
I am trying to enable VC 4 driver in archlinux latest kernel now, without xorg.conf but face blackscreen. I have read the /var/log/Xorg.0.log, found
$this->bbcode_second_pass_code('', '[ 13.296] (II) modeset(0): Output HDMI-1 has no monitor section
[ 13.296] (II) modeset(0): EDID for output HDMI-1
[ 13.296] (II) modeset(0): Output HDMI-1 disconnected
[ 13.296] (WW) modeset(0): No outputs definitely connected, trying again...
[ 13.296] (II) modeset(0): Output HDMI-1 disconnected
[ 13.296] (WW) modeset(0): Unable to find connected outputs - setting 1024x768 initial framebuffer
[ 13.296] (II) modeset(0): Using default gamma of (1.0, 1.0, 1.0) unless otherwise stated.
[ 13.296] (==) modeset(0): DPI set to (96, 96)
')
I don't think it's caused by kernel, since I can boot on Raspbian Jessie with VC4 driver, which kernel is 4.4.9- v7.
I guess it's trying to use the wrong monitor, it should be HDMI-0 according to Xorg.0.log from success boot with fbturbo driver.
But I don't know how to set HDMI-0 as default monitor. I have tried xrandr, but got:
$this->bbcode_second_pass_code('', 'xrandr: Failed to get size of gamma for output default ')
compared to xrandr output on Raspbian :
$this->bbcode_second_pass_code('', 'Screen 0: minimum 320 x 200, current 1366 x 768, maximum 2048 x 2048
HDMI-0 connected 1366x768+0+0 (normal left inverted right x axis y axis) 256mm x 144mm
1366x768 60.00*+
720x576 50.00
720x480 60.00 59.94
640x480 60.00 59.94')
Can you give some hints with how to set default monitor on archlinux arm?