[U-Boot] some questions about u-boot

[Wolfgang Denk]

Dear li guohu,

please keep the mailing list on Cc:

In message <BLU166-W3176968F6747D75C62C676C6360 at phx.gbl> you wrote:
>  
> Thanks for your detailed help. I have solved the second question based on your answer. 

Good.

> > > 1. Before the u-boot enter the command line, some error like "Error:
> > > environment overflow " happens. The space in the ram used to save the
> > > environment variables are 0x2000. I think this is enough. I set this
> > > space in the head file like this: #define CON FIG_SYS_ENV_SIZE
> > > 0x2000.
> 
> Yes, I am using the old version of the u-boot.  The version is U-Boot 2009.03.
> How can I deal with this warning? I mean, if I don't change a new version.
> Why this vwarning happens?

Eventually your assumption ("I think this is enough.") is wrong?
Check the source code where and why this message is printed - grep is
your friend.

> > > 3. After the u-boot enter the command line, I enter the command "mii
> > > info". But nothing appears. If I enter the command "mii read 0x1
> > > 0x1", I can only see 0xFFFF. If I ping some address, I can see 32
> > > lines if I use the "mii info" then. The address of th e PHY is 0x1.
> > 
> > You probably have some misconfiguration in your port.
> 
> I have checked the port configuration carefully. I think it is correct. 

The golden rule is: if everything is correct, it will work.  So there
must be a problem somewhere.

> The board I am using is made by myself based on the board TWR-MPC5125 made by freescale.
> This is a difficult question. I think maybe the hardware has some errors because I can't not see
> any output from the PHY. But I can see the signal from the CPU in the MDC pin and the MDIO pin 
> of the PHY. Compared with the signals of the TWR-MPC5125, I think they are correct. 		 	   		  

There is many things you may need (or fail) to configure for a PHY.
How are clocks generated?  Does it need a special reset handling, sya,
through a GPIO or similar?  Does it need any other initialization?  Is
it a supported or standard PHY type?  There are so many questions we
cannot help you with because we know neither the hardware nor the
code.

So this is a MPC5125 based system?  Well, code for this processor has
never been mainlined; I remember that it is sufficiently different
from the other members of the MPC512x family to make it largely
incompatible.  I would not be surprised if there were a number of bugs
in that out-of-tree port.

> --_8ea4e2c9-4b0d-4e26-9643-f0b60da03b1b_
> Content-Type: text/html; charset="gb2312"
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Please stop posting HTML!!

Best regards,

Wolfgang Denk

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