Hi,
On 29-03-15 17:55, Karsten Merker wrote:
config_distro_bootcmd.h defines a common boot environment for multiple platforms. Document the format of the console environment variable to allow the use of generic boot scripts on all supported platforms.
Signed-off-by: Karsten Merker merker@debian.org
Maybe add something that distros are not encouraged to use this ?
At least on Fedora we do not want to use it, as adding console=${console} to bootargs on systems with both video-output (e.g. hdmi out) and a serial port will cause boot messages to only be shown on the serial port as that is where the /dev/console then points.
Whereas when using the devicetree chosen/stdout-path property (which can be set either by u-boot or in the dts with the kernel), the kernel will use both /dev/tty0 (so the hdmi out) and the serial port pointed to by chosen/stdout as console, showing boot messages on both, and systemd will still automatically spawn a getty on the serial console.
Regards,
Hans
doc/README.distro | 9 +++++++++ 1 file changed, 9 insertions(+)
diff --git a/doc/README.distro b/doc/README.distro index 0308a4c..3f7ee85 100644 --- a/doc/README.distro +++ b/doc/README.distro @@ -201,6 +201,15 @@ variables be set. Default values for these variables are often hard-coded into CONFIG_EXTRA_ENV_SETTINGS in the board's U-Boot configuration file, so that the user doesn't have to configure them.
+console:
Mandatory. The default console device to be passed to the Linux kernel.
The console device is specified in accordance with the guidelines
described in Documentation/serial-console.txt in the Linux kernel sources.
If the device is a serial port, the console variable must specify the
console baudrate in addition to the console device, e.g. "ttyS0,115200".
fdt_addr:
Mandatory for any system that provides the DTB in HW (e.g. ROM) and wishes