topic Serial console does not display properly for Android 4.4 BSP in i.MX Processors

Serial console does not display properly for Android 4.4 BSP

changyuheng — Tue, 27 Jan 2015 03:02:59 GMT

Hello All:

Default console debug port was set in UART1 for mother board, but our customer IMX6 board was setting for UART3.

The console shows random unstable since turn UART1 to UART3 as follow:

root@sabresd_6dq:/ #

root@sabresd_6dq:/ # UV

;kdlsrequest_suspend_state: wakeup (3->0) at 26127490005 (2015-01-27 02:54:39.635235336 UTC)

eth0: Freescale FEC PHY driver [Generic PHY] (mii_bus:phy_addr=1:04, irq=-1)

ADDRCONF(NETDEV_UP): eth0: link is not ready

acc_open

acc_release

ehci_fsl_bus_resume begins, DR

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I have no idea to fix this issue, modify code as follow:

arch/arm/configs/imx6_android_defconfig:

CONFIG_CMDLINE="noinitrd console=ttymxc2,115200 root=/dev/mtdblock2 rw rootfstype=jffs2 ip=off

arch/arm/mach-mx6/board-mx6q_sabresd.c:

static void __init mx6_sabresd_timer_init(void)

#endif

mx6_clocks_init(32768, 24000000, 0, 0);

- uart_clk = clk_get_sys("imx-uart.0", NULL);

- early_console_setup(UART1_BASE_ADDR, uart_clk);

+ uart_clk = clk_get_sys("imx-uart.2", NULL);

+ early_console_setup(UART3_BASE_ADDR, uart_clk);

}

arch/arm/mach-mx6/board-mx6q_sabresd.h:

MX6Q_PAD_SD4_CLK__UART3_RXD,

MX6Q_PAD_SD4_CMD__UART3_TXD,

this way is work for ubuntu BSP, so I don't know why android OS has this problem.

Please kindly teach me how to fix it!

Thanks.

Re: Serial console does not display properly for Android 4.4 BSP

jimmychan — Fri, 30 Jan 2015 08:23:42 GMT

Please see this.

https://community.freescale.com/thread/308092

please check init.rc.

Re: Serial console does not display properly for Android 4.4 BSP

albertlim — Tue, 14 Jun 2016 01:33:59 GMT

Hi Public Account,

I am seeing these coming out from UART 3. Have you resolved your problem. I5ts very much appreciated if your could give me some hint

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I would need to know where these came from and how to disable them . The baud rate is 115.2kbps. These looks to me like some command sent out from some driver

Thanks a bunc

Regards

Albert

Re: Serial console does not display properly for Android 4.4 BSP

jimmychan — Tue, 14 Jun 2016 03:21:01 GMT

this may help you BSP 13.4.1.04 android boot up issue

Re: Serial console does not display properly for Android 4.4 BSP

albertlim — Fri, 17 Jun 2016 01:25:12 GMT

Thanks Jimmy. The UART setting is fine. I've found the problem, some driver is using the UART3 and I have manage to disable it.