omapl138 linux系统下串口对应设备节点是哪个？

您可以参考下面帖子里要修改的地方
e2e.ti.com/.../684102

arch/arm/boot/dts/da850-lcdk.dts

aliases {
serial2 = &serial2;
ethernet0 = &eth0;
};

chosen {
stdout-path = "serial2:115200n8";
};

u-boot/include/configs/omapl138_lcdk.h
/*
* Serial Driver info
*/
#define CONFIG_SYS_NS16550_SERIAL
#define CONFIG_SYS_NS16550_REG_SIZE -4 /* NS16550 register size */
#define CONFIG_SYS_NS16550_COM1 DAVINCI_UART2_BASE /* Base address of UART2 */
#define CONFIG_SYS_NS16550_CLK clk_get(DAVINCI_UART2_CLKID)
#define CONFIG_CONS_INDEX 1 /* use UART0 for console */
#define CONFIG_SYS_BAUDRATE_TABLE { 9600, 19200, 38400, 57600, 115200 }



#define CONFIG_EXTRA_ENV_SETTINGS \
DEFAULT_LINUX_BOOT_ENV \
DEFAULT_MMC_TI_ARGS \
"bootpart=0:2\0" \
"bootdir=/boot\0" \
"bootfile=zImage\0" \
"fdtfile=da850-lcdk.dtb\0" \
"boot_fdt=yes\0" \
"boot_fit=0\0" \
"console=ttyS2,115200n8\0"

In kernel you need to modify da850-lcdk.dts:
chosen {
stdout-path = "serial2:115200n8";
};