Can't get serial SMC1 and SMC2 working together

Kenneth Poole kpoole at
Tue Apr 4 07:05:13 EST 2006

>I'm using a TQM823L board, ELDK and Linux 2.4.25 (from denx). My
>problem is that i can't use both SMC1 and SMC2 at the same time when I
>disable the console

Serial port interactions can result from incorrect mapping of the baud
rate generators (BRGs) to the ports.
I'm looking at source from 2.4.19, and this may have changed, but the
serial driver init function
(rs_8xx_init) calls m8xx_cpm_setbrg() with 'baud_idx' as the argument
that selects which BRG. 'baud_idx' is set in serial_console_setup(). If
you don't configure a console, 'baud_idx' may not be initialized.

In any event, make sure that the BRGs are mapped to the ports as
required for your specific board.

Ken Poole
MRV Communications, INC.

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