powerpc port for sbc8260-based board problem

Boris Shteinbock bshtein at yahoo.com
Wed May 7 18:31:52 EST 2008

I am doing a port from ppc to powerpc ARCH on sbc8260 based board.
The problem is, that I can't get  SMC1 UART to work.
After SMC console  is initialized.  
cpm_uart_console_write() hangs here

        /* Wait for transmitter fifo to empty.
         * Ready indicates output is ready, and xmt is doing
         * that, not that it is ready for us to send.
        while ((in_be16(&bdp->cbd_sc) & BD_SC_READY) != 0)

I am using dts tree modified  from ep8248 port since it is the only one that has smc description in it. :

     brg at 119f0 {
       compatible = "fsl,mpc8260-brg",
       reg = <119f0 10 115f0 10>;
       clock-frequency = <135000000>;

     /* Monitor port/SMC1 */
     smc1: serial at 11a80 {
       device_type = "serial";
       compatible = "fsl,mpc8260-smc-uart",
       reg = <0x11a80 0x20 0x1100 0x40>;
       interrupts = <4 8>;
       interrupt-parent = <&PIC>;
       fsl,cpm-brg = <1>;
       fsl,cpm-command = <0x1d000000>;
       linux,my-label = "SMC1";

I checked a BRG settings against working u-boot configuration and they are the same. Anyway a wrong BRG setting wouldn't hang this loop

So I have a few questions.
If someone has done sbc8260 dts tree and port to "powerpc" already, I'd be very  grateful if he can share it with me.
I couldn't find anything on the internet.

Can someone, also, explain, how "fsl, cpm-command" field works,  booting-without-of document doesn't provide much information.
I feel, that just copying this value from ep8248.dts isn't right somehow.

Thank you

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