Hi, Simon,
On 1 March 2016 at 02:06, Alison Wang b18965@freescale.com wrote:
When LCD/HDMI is connected to LS1021ATWR or LS1021AQDS, the console output should be shown on the monitor.
If CONFIG_DM_SERIAL and CONFIG_DM_STDIO are both enabled, serial device is registered and added to the stdio list in serial-uclass.c. Then, vga device will be registered and added to the stdio list in
cfb_console.c.
So serial device is at the head of the stdio list and will be chosen as the input and output device in console_init_r(). It will cause the console output can't be shown on the monitor.
If CONFIG_DM_STDIO is disabled when using CONFIG_DM_SERIAL. First, vga device is registered and added to the stdio list in cfb_console.c. Then serial device will be registered and added to the stdio list in drv_system_init(). So vga device is at the head of the stdio list and will be chosen as the input and output device in console_init_r(). The console output will be shown on the monitor.
The patch is to disabled CONFIG_DM_STDIO for LCD/HDMI display.
Signed-off-by: Alison Wang alison.wang@nxp.com
Have you tried enabling CONFIG_CONSOLE_MUX?
[Alison Wang] Thanks for your advice. I got your idea, and tried to enable CONFIG_CONSOLE_MUX and CONFIG_SYS_CONSOLE_IS_IN_ENV. Then after setting "stdout=serial,vga", the console output is both shown on monitor and serial terminal.
This patch is not a good way to fix the problem, please abandon it. Enabling CONFIG_SYS_CONSOLE_IS_IN_ENV is the best way to fix the problem, and Enabling CONFIG_CONSOLE_MUX could be used to shown the console output on multiple devices simultaneously.
Best Regards, Alison Wang