ep8260 board linux port serial port problem

Steven Blakeslee BlakesleeS at embeddedplanet.com
Wed Dec 31 04:26:27 EST 2003

You may need to turn the pipelining on.  Some 8260 processor's CPM loses
communication with the SDRAM when Linux runs, enabling pipelining will solve
this.  Also, make sure Linux is properly getting the information for the
SDRAM size.

-----Original Message-----
From: Kiran Mandava [mailto:kiran.mandava at skystream.com]
Sent: Tuesday, December 30, 2003 12:11 PM
To: linuxppc-embedded at lists.linuxppc.org
Subject: ep8260 board linux port serial port problem

Hello All,

	I am trying to bringup linux 2.4.22 on ep8260 board. i have the
U-boot running fine. while booting the linux kernel the execution path is
looping in serial_console_write(verified it thr'u JTAG).SMC1 is configured
as the console.

      For the SMC port the code is setting up the proper Rx/Tx descriptors
in the on chip DPRAM and it tries to use the actual buffers from the RAM (on
the 6xx bus in this case) the code loops in the serial_console_write, but if
i change the actual buffers to be from the on chip DPRAM itself the serial
port works fine.(I guess this is how it is done in the U-boot too)..did
someone face the similar probelm, any sugestions would be greately

      RAM seems to be working fine, as the code gets relocated properly to
RAM and executes from there.


>-----Original Message-----
>From: Kiran Mandava [mailto:kiran.mandava at skystream.com]
>Sent: Thursday, December 18, 2003 11:44 AM
>To: linuxppc-embedded at lists.linuxppc.org
>Subject: ep8260 board linux port
>Hello All,
>  I am trying to port linux 2.4.22 onto ep8260 board. (256 MB
>RAM on 6xx
>bus/ 32 MB Flash) using tools and source code from denx webisite.
>  I was able to port u-boot and trying to boot linux now.
>  i couldn't find any specific files to this board in the
>platform directory
>although est8260.h file has the basic bd structure. the
>problem i am facing
>is the processor loops in serial_console_write/ timer
>interrupt handler. i
>made sure that i am passing the baudrate proeprly by looking at the bd
>structure while passing teh control to start_kernel function.
>  My console does display everything properly running u-boot
>but once the
>control goes to linux don't see anything on the console.
>i made only the following changes for th elinux boot.
>	1. in uart.c made sure that the console port is defines as SMC1.
>	2. defines the SMC2 to be serial port too
>      3. FCC3 is configured as the ethernet.
>and compiled and tried to boot the image, but i couldn't. i do
>have a BDI
>JTAG device and i was able to see the RAM properly.
> could some one throw light on what i could be doing wrong,
>any sugestions
>are greatley appreciated. I bet some one would have done this
>years before..

** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/

More information about the Linuxppc-embedded mailing list