Uart3 and Uart4 cann't work normally on MX6D platform

[tangyuan]

Hi:

I am using uart3 and uart4 on mx6d platform.But uart3 and uart4 cann't send and receive data all the time!

I already check the definition in board_mx6q_sabresd.h:

MX6Q_PAD_EIM_D24__UART3_TXD,
MX6Q_PAD_EIM_D25__UART3_RXD,
MX6Q_PAD_EIM_D23__UART3_CTS,
MX6Q_PAD_EIM_D31__UART3_RTS,

At the same time ,i found the function register as follows:

  imx6q_add_imx_uart(4, NULL);
  imx6q_add_imx_uart(3, NULL);
  imx6q_add_imx_uart(2, NULL);
  imx6q_add_imx_uart(1, NULL);
  imx6q_add_imx_uart(0, NULL);

Can anyone help me ,uart3 and uart4 cann't send and receive data.

[igorpadykov]

Hi tang

uart4 is used on sabre auto board, please check uboot/include/configs/mx6qsabreauto.h

uboot-imx.git - Freescale i.MX u-boot Tree 

use linux build imx6qsabreauto configuration as in attached Yocto Guide

sect.5.1 Build configurations

Best regards
igor
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[tangyuan]

HI,

      igorpadykov

             My kernel is linux3.0.35.

             I doubt now whether the definition of multi - functional pin multiplexing is wrong.

             Can you check it for me?

             #define _MX6Q_PAD_EIM_D25__UART3_RXD \
IOMUX_PAD(0x03CC, 0x00B8, 2, 0x0930, 1, 0)

            #define _MX6Q_PAD_EIM_D24__UART3_TXD \
IOMUX_PAD(0x03C8, 0x00B4, 2, 0x0000, 0, 0)