New subject: [U-Boot-Users] A question about initialization of SDRAM

24 Nov 2005

      Thanks for your reply!
I had tried several different version of ppc_8xx-gcc to build the same u-boot.Only version 3.2.1 works ok.
All the others(3.2.2, 3.3.1 and 3.3.3) have the problem that I have said before. So I think that maybe there is
something different between these versions of gcc. Would you please explain it to me? Thanks a lot.
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In message Tx948882797899.26592@send2.inner-21cn.com you wrote:
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I am trying to use ELDK to make a u-boot on the board with MPC852T.

"the board with MPC852T"? There is many such boards, most of them differnt.
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There is declaration of rtx in cpu/mpc8xx/fec.c:

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static RTXBD *rtx = NULL;

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I think that "rtx" should be NULL at the first time fec_init() is entered,so the rtx will be given the value.
but after the ELDK make the u-boot, "rtx" isn't NULL at the first time fec_init() is entered, it is 0xffffffff.

What makes you think so? The code is running perfectly fine  on  many
boards. Which specific problem do you see?
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Before the word "memctl->memc_mbmr  = 0xD0924114" in the function initdram, rtx is NULL(0x0),but after that it
is 0xffffffff. Part of the fuction initdram is below:

Looks as if there was a bug in the SDRAM init sequence for your board.
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I wonder what happens in "memctl->memc_mbmr  = 0xD0924114;",would you please explain it to me ? Thanks!
Please see the processor's User's Manual; read the memory  controller
section.
Best regards,
Wolfgang Denk
-- 
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
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蔡潋滟
　　　　　　　　killercai@21cn.com
　　　　　　　　　　2005-11-24

Re: Re: [U-Boot-Users] A question about initialization of SDRAM

蔡潋滟

Wolfgang Denk

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