1The config option CONFIG_SILENT_CONSOLE can be used to quiet messages 2on the console. If the option has been enabled, the output can be 3silenced by setting the environment variable "silent". 4 5- CONFIG_SILENT_CONSOLE_UPDATE_ON_SET 6 When the "silent" variable is changed with env set, the change 7 will take effect immediately. 8 9- CONFIG_SILENT_CONSOLE_UPDATE_ON_RELOC 10 Some environments are not available until relocation (e.g. NAND) 11 so this will make the value in the flash env take effect at 12 relocation. 13 14The following actions are taken if "silent" is set at boot time: 15 16 - Until the console devices have been initialized, output has to be 17 suppressed by testing for the flag "GD_FLG_SILENT" in "gd->flags". 18 19 - When the console devices have been initialized, "stdout" and 20 "stderr" are set to "nulldev", so subsequent messages are 21 suppressed automatically. Make sure to enable "nulldev" by 22 enabling CONFIG_SYS_DEVICE_NULLDEV in your board defconfig file. 23 24 - When booting a linux kernel, the "bootargs" are fixed up so that 25 the argument "console=" will be in the command line, no matter how 26 it was set in "bootargs" before. If you don't want the linux command 27 line to be affected, define CONFIG_SILENT_U_BOOT_ONLY in your board 28 config file as well, and this part of the feature will be disabled. 29