iMX28 Boot linux to use AUART as console instead of DUART

[bdp42]

We have an iMX28 based platform running linux 2.6.35, built using LTIB

I want to use one of the AUARTS (ttySP2) as the console instead of DUART (ttyAM0)

I configured the iomux for AUART2 operation, configured CONFIG_SERIAL_MXS_AUART_CONSOLE=y in the kernel and changed the boot command line to use ttySP2 as the console (console=/dev/ttySP2,115200 rdinit=linuxrc rw gpmi).

As far as I know this is all I need to do.

However the kernel starts and appears to simply hang and nothing gets printed on the /dev/ttySP2 interface. Everything works fine when I set the boot command line to use /dev/ttyAM0 as the console.

Is it possible to do this and is there something else I need to do to get it to work.

Thanks,

Bruno

[igorpadykov]

Hi Bruno

one can check HW_UARTAPP_CTRL2 register, bit CTSEN - CTS Hardware Flow Control Enable:
"If this bit is set to 1, CTS hardware flow control is enabled. Data is only
transmitted when the nUARTCTS signal is asserted. "
Similar issues were described on
https://community.nxp.com/thread/321357
https://community.nxp.com/thread/302715

Best regards
igor
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