Hello, I have a Freescale P1014 custom board with the UARTs connected as follows: UART0 -> BMM (Board management device connected to sensors) ttyS0 115200 bauds UART1 -> Not used. Disable in the device tree. UART2 -> Console. ttyS1 - 9600 bauds UART3 -> Not used. ttyS2 I am using Linux 3.14 The bootargs specifices console=ttyS1,9600n8 I have two issues: When booting a few lines of garbage characters are printed when ttyS0 is probed. serialªrÒÒ¢ÑåMÅÑyS0 at MMIO 0xffe04500 (irq = 42, base_baud = 20833333) is a 165 ÑÑ55%=ÁááÁÑÝÁÁÑ¡¥ÉÅÉõÑɱõ± ÍÍ}½¹Íͽ¹Íͽ±mÕÕѹ¹ loaded ±5)½½Ñ½¹Íͽ±mÕÕÍÍ 5)½½ÑÑ ... Later the system reached the prompt. These type of character also appears when setting UART0 to 9600/115200 bauds in the boot loader or not programming the speed at all. This does not happen when UART0 is disabled in the device tree. I do not understand why Linux would attempt to use ttyS0 when the console is specified as ttyS1. Is there a way to prevent this behaviour? Next, if I do not program a baud rate in UART0 from the boot loader and use for instance the command stty -F /dev/ttyS0. There is an interrupt flood and Linux hangs. The same happen when using the tools accessing the BMM. No character seems to be transmitted or received. Note that I need to spent for time gathering data on this issue. I am looking for a way to solve the first issue. I was thinking to get ttyS1 (UART2) to be probed first and see whether that would prevent these characters from being printed or any other possible solution to test. Though, I am not sure how this can be accomplished after looking at boot argument controlling console access or changing the device tree. I would appreciate any suggestions. Cheers, Renaud -- To unsubscribe from this list: send the line "unsubscribe linux-console" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
