What to change on u-boot if we want to remove SPD EEPROM?

What to change on u-boot if we want to remove SPD EEPROM?

[Bruno Li]

Hi:

We want to remove SPD EEPROM on ppc440gp to lower the
expense. The plan is to change u-boot code to use a
memory buffer (filled with the content of SPD EEPROM).
Is this possible?

I removed the SPD EEPROM on my ppc440gp board, and
changed u-boot code to use a memory buffer whenever
the code need to access SPD EEPROM, however, I found
that pci bus scan fails, u-boot stops at this line (of
pci_hose_scan_bus() in drivers/pci.c:
pci_hose_read_config_byte(hose, dev, PCI_HEADER_TYPE,
&header_type);

What extra initialization should I do when SPD EEPROM
is missing from the system?

Thanks,

Bruno


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Re: What to change on u-boot if we want to remove SPD EEPROM?

[Wolfgang Denk]

In message <20030612014745.47244.qmail@web41509.mail.yahoo.com> you wrote:
>
> We want to remove SPD EEPROM on ppc440gp to lower the
> expense. The plan is to change u-boot code to use a
> memory buffer (filled with the content of SPD EEPROM).
> Is this possible?

Yes, it is. Actually only  very  few  systems  use  memory  with  SPD
EEPROMs.

> I removed the SPD EEPROM on my ppc440gp board, and
> changed u-boot code to use a memory buffer whenever
> the code need to access SPD EEPROM, however, I found

You should implement a proper initialization function for your memory
instead.

> What extra initialization should I do when SPD EEPROM
> is missing from the system?

This depends on your hardware (type of memory etc.).


Please note that such questions ore of topic here. You will  probably
receive more / better response on the u-boot-users mailing list.


Best regards,

Wolfgang Denk

--
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-4596-87  Fax: (+49)-8142-4596-88  Email: wd@denx.de
Drun'? 'm not drun'! You woudn' dare call m' drun' if I was sober!
                                     - Terry Pratchett, _Men at Arms_

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