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Date: Fri, 10 Aug 2007 21:43:41 -0400
From: "mike zheng" <mail4mz@gmail.com>
To: linuxppc-dev@ozlabs.org.
Subject: Early UART setup on 2.6 kernel for mpc85xx
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Hi All,

In order to debug the kernel 2.6, I want setup serial port with UART on
mpc85xx as early as possible. I add the register access code at the
beginning of  platform_init(). For example, I try to write THR
register(0xe0004500). However the system just hanging there with this line.
If I comment out this line, everything works fine.

Here is the code my mpc85xx_cds_common.c:

void __init
platform_init(unsigned long r3, unsigned long r4, unsigned long r5,
                   unsigned long r6, unsigned long r7)
{

....
}

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<div>Hi All,</div>
<div>&nbsp;</div>
<div>In order to debug the kernel 2.6, I want setup serial port with UART on mpc85xx as early as possible. I add the register access code&nbsp;at the beginning of &nbsp;platform_init(). For example, I try to write THR register(0xe0004500). However the system just hanging there with this line. If I comment out this line, everything works fine. 
</div>
<div>&nbsp;</div>
<div>Here is the code my mpc85xx_cds_common.c:</div>
<div>&nbsp;</div>
<div>void __init</div>
<div>platform_init(unsigned long r3, unsigned long r4, unsigned long r5, </div>
<div>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; unsigned long r6, unsigned long r7)</div>
<div>{</div>
<div>&nbsp;</div>
<div>....</div>
<div>}&nbsp;</div>
<div>&nbsp;</div>
<div>&nbsp;</div>
<div>&nbsp;</div>

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