| wdenk | f72da34 | 2003-10-10 10:05:42 +0000 | [diff] [blame] | 1 | The config option CONFIG_SILENT_CONSOLE can be used to quiet messages |
| 2 | on the console. If the option has been enabled, the output can be |
| 3 | silenced by setting the environment variable "silent". The variable |
| 4 | is latched into the global data at an early stage in the boot process |
| 5 | so deleting it with "setenv" will not take effect until the system is |
| 6 | restarted. |
| 7 | |
| 8 | The following actions are taken if "silent" is set at boot time: |
| 9 | |
| 10 | - Until the console devices have been initialized, output has to be |
| 11 | suppressed by testing for the flag "GD_FLG_SILENT" in "gd->flags". |
| wdenk | f72da34 | 2003-10-10 10:05:42 +0000 | [diff] [blame] | 12 | |
| 13 | - When the console devices have been initialized, "stdout" and |
| 14 | "stderr" are set to "nulldev", so subsequent messages are |
| 15 | suppressed automatically. Make sure to enable "nulldev" by |
| Jean-Christophe PLAGNIOL-VILLARD | 6d0f6bc | 2008-10-16 15:01:15 +0200 | [diff] [blame] | 16 | #defining CONFIG_SYS_DEVICE_NULLDEV in your board config file. |
| wdenk | f72da34 | 2003-10-10 10:05:42 +0000 | [diff] [blame] | 17 | |
| 18 | - When booting a linux kernel, the "bootargs" are fixed up so that |
| 19 | the argument "console=" will be in the command line, no matter how |
| 20 | it was set in "bootargs" before. |