powerpc/85xx: Add memory test feature for mpc85xx.

Wolfgang,

As Timur pointed out, the post framework doesn't work for us. After U-boot relocate itself to RAM, we have only 2GB memory to test. The best place is before relocation. Many other boards do that. Following your idea of reusing code, I can only reuse the test pattern generator. I am open to suggestions.

York Sun
----- Original Message -----
From:"Wolfgang Denk" <[email protected]>
To:"York Sun" <[email protected]>
Cc:"Timur Tabi" <[email protected]>, "Kumar Gala" <[email protected]>, "u-boot at lists.denx.de" <[email protected]> Sent:7/28/2010 4:50 PM
Subject:Re: [U-Boot] [PATCH 8/8] powerpc/85xx: Add memory test feature for mpc85xx.

Dear York Sun,

NAK, and NAK.

Please integrate your code into the existing POST framework instead, as a number of other boards already did.

A progress indicator may be a nice little toy, but how does it integrate into the POST framework?

Yes, memory testing takes time. In the context of a power-on self test (and this is what you are doing, right?) we should take care to fit it into the existing framework, though.

Instead of integrating your needs into an existing framework you invent yet another one. I don't want to have this, sorry.

Best regards,

Wolfgang Denk

DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
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Dear sun york-R58495,

And I explained that if it doesn't work as is please try to adapt / extend it to match your needs instead of reinventing the wheel.

I don't understand what you are saying. You sound as if you assumed that the POST code would run after relocation only? This is NOT the case. THere are tests that run before relocation (incluing the RAM test), and others, that run after relocation.

I suggest to check the code again, or to explain in a little more detail why you think you can neither use nor extend the existing framework.

Best regards,

Wolfgang Denk

DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
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Wolfgang,

Please help me to understand the post_word_write() and post_word_load(). I see some implementations which don't use NVRAM. Is it OK to use gd? Does the post_word_load() require the data survive reset? How is the data validated? I don't see any code to validate the value.

Regards,

York

Dear York Sun,

No.

Yes.

It checks against BOOTMODE_MAGIC.

Best regards,

Wolfgang Denk

DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
Faith may be defined briefly as an illogical belief in the  occurence
of the improbable.                                    - H. L. Mencken

Dear Wolfgang,

Thanks for the quick respond.

What's if I don't want to use flash and don't have NVRAM? Can I use gd but let it fail the validation in case of data corruption?

York

Dear York Sun,

I don't understand the problem. All we need is some register or memory location that is guaranteed to keep it's value during a hard reset of the processor. This can be NVRAM, or On-Chip-Memory, or some register. I am pretty sure you know this CPU much better than me, and I am optimistic that you can find such a register.

Best regards,

Wolfgang Denk

DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
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