thoughts and questions on 8xx patches

Wolfgang Denk wd at
Tue Sep 21 20:40:29 EST 2004

In message <Pine.LNX.4.60.0409210605090.9033 at> you wrote:
>    rather than get into more detailed discussion on microcode patches, 
> here's a (partial) patch that represents what i'd really, really, 
> *really* like to see.
> +config I2C_SPI_PATCH
> +	bool "I2C/SPI relocation patch"
> +
> +config I2C_SPI_SMC1_PATCH
> +	bool "I2C/SPI/SMC1 relocation patch"

Why? As far as I understand the I2C/SPI patch has been obsolteted  by
the I2C/SPI/SMC1 patch. So only the latter is needed.

>    it adds a simple choice entry to the MPC8xx menu, from which you can 
> select the appropriate patch -- it's as easy as that.

No, it is not that easy.

>    note that that's not the entire list of possible patches -- i have 
> the list from wolfgang's tree that distinguishes between 850 and 8xx 
> (non-850) patches in some cases so the list is actually longer than 
> this one.  but, really, selecting a patch should be this easy -- pick 

Indeed. And AFAICT there is no way to get the processor version  from
any  other CONFIG option that the board name, so this would become an
awfully long list.

> one and check the box.  and this makes it trivial to add or delete 
> patches appropriately as time goes by.
>    obviously, this menu requires changes in the underlying micropatch.c 
> file (which aren't shown here), but i'm curious about whether this 
> approach would overly offend anyone.

This has been discussed many times before. 

>    i'm willing to create the overall patch to support this, but not if 
> it's just going to be tossed because of philosophical positions.

It's technical issues, too. There was a decision not to configure for
a specific variant of the 8xx processor, and so it becomes cumbersome
to add "convenient" configuration options  which  depend  on  exactly
this information.

Best regards,

Wolfgang Denk

Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-4596-87  Fax: (+49)-8142-4596-88  Email: wd at
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