How to disable boot and kernel log output on HDMI out

[slip76]

The device is based on Jetson AGX Xavier. I need to hide any stuff that can help to identify the OS for kiosk device. I've already replaced nvidia logo with the custom one. Now trying to get rid of any messages on the screen during boot.
Found a bit of information but it is for nvidia SDK or for different platform. I've tried the following but this does not help:

repos/meta-tegra$ git diff
diff --git a/conf/machine/include/tegra-common.inc b/conf/machine/include/tegra-common.inc
index e8f7e7d0..492ec4f8 100644
--- a/conf/machine/include/tegra-common.inc
+++ b/conf/machine/include/tegra-common.inc
@@ -10,7 +10,7 @@ UBOOT_EXTLINUX ?= "1"
 UBOOT_EXTLINUX_FDTDIR ?= ""
 UBOOT_EXTLINUX_ROOT ?= "${cbootargs} ${KERNEL_ROOTSPEC}"
 # Console setting comes from ${cbootargs}
-UBOOT_EXTLINUX_CONSOLE = ""
+UBOOT_EXTLINUX_CONSOLE = "console=tty1"
 UBOOT_EXTLINUX_KERNEL_ARGS ?= "${bootargs}"
 UBOOT_EXTLINUX_INITRD ?= "${@'../initrd' if d.getVar('INITRAMFS_IMAGE') != '' and d.getVar('TEGRA_INITRAMFS_INITRD') == '1' else ''}"

diff --git a/conf/machine/jetson-xavier.conf b/conf/machine/jetson-xavier.conf
index a51874cd..416b3370 100644
--- a/conf/machine/jetson-xavier.conf
+++ b/conf/machine/jetson-xavier.conf
@@ -5,7 +5,7 @@
 require conf/machine/include/tegra194.inc

 KERNEL_DEVICETREE ?= "_ddot_/_ddot_/_ddot_/_ddot_/nvidia/platform/t19x/galen/kernel-dts/tegra194-p2888-0001-p2822-0000.dtb"
-KERNEL_ARGS ?= "console=ttyTCU0,115200 console=tty0 fbcon=map:0"
+KERNEL_ARGS ?= "console=tty1 fbcon=map:0"

 EMMC_SIZE ?= "31276924928"
 EMMC_DEVSECT_SIZE ?= "512"

[madisongh]

Try KERNEL_ARGS ?= "console=ttyTCU0,115200 fbcon=map:0 quiet". That will direct the kernel messages to the serial console, rather than the video display; adding the quiet parameter reduces the amount of logging the kernel does (and systemd, too). The U-boot setting isn't needed, since you're not likely to be using U-Boot in your builds.

[slip76]

@madisongh thanks a lot - your solution perfectly solves my needs. One more question - how can I override this setting in my distro not to touch anything in "meta-mender"?

[madisongh]

Adding the following to your distro configuration file should take care of it:

KERNEL_ARGS_remove_jetson-xavier = "console=tty0"
KERNEL_ARGS_append_jetson-xavier = " quiet"