在IMX6qp上移植了linux-imx-imx_4.1.15_2.0.0_ga系统后,发现kernel uart没有任何打印,停留在uboot的打印”Starting kernel ...“ uart 这里 。管脚定义如下:
pinctrl_uart1: uart1grp {
fsl,pins = <
//MX6QDL_PAD_CSI0_DAT10__UART1_TX_DATA 0x1b0b1
//MX6QDL_PAD_CSI0_DAT11__UART1_RX_DATA 0x1b0b1
MX6QDL_PAD_SD3_DAT7__UART1_TX_DATA 0x1b0b0
MX6QDL_PAD_SD3_DAT6__UART1_RX_DATA 0x1b0b0
>;
};
已经屏蔽了其他使用SD3_DAT7 ,SD3_DAT6的配置,。
如果屏蔽到内核的LDB 功能,“#CONFIG_FB_MXC_LDB=y “, uart能正常打印。
相同管脚定义和配置, 在6D上uart能正常打印(不需要屏蔽LDB功能)。 所以应该是6qp和6d的区别导致,请教下,这个问题如何定位?
附件为内核配置和相关设备树。
Hello Yang,
From these 2 pins, SD3_DAT7 & SD3_DAT6, UART1 TX & RX can be multiplexed, they are no relations to LDB module.
I checked imx6qdl-sabresd.dtsi you pasted here, in the file, IOMUX has been done for 2 times:
pinctrl_uart1: uart1grp {
fsl,pins = <
MX6QDL_PAD_SD3_DAT7__UART1_TX_DATA 0x1b0b0
MX6QDL_PAD_SD3_DAT6__UART1_RX_DATA 0x1b0b0
>;
};
pinctrl_uart2: uart2grp {
fsl,pins = <
MX6QDL_PAD_SD3_DAT4__UART2_RX_DATA 0x0001B0B0
MX6QDL_PAD_SD3_DAT5__UART2_TX_DATA 0x0001B0B0
>;
};
pinctrl_uart3: uart2grp {
fsl,pins = <
MX6QDL_PAD_EIM_D24__UART3_TX_DATA 0x0001B0B0
MX6QDL_PAD_EIM_D25__UART3_RX_DATA 0x0001B0B0
>;
};
pinctrl_uart4: uart4grp {
fsl,pins = <
MX6QDL_PAD_SD3_DAT6__UART1_RX_DATA 0x0001B0B0
MX6QDL_PAD_SD3_DAT7__UART1_TX_DATA 0x0001B0B0
>;
};
check it please!
have a nice day!
NXP TIC Weidong sun
Thank you , i have update the uart4' config. But i also have no print info on uart1. how can debug this issue?