Re: Does HIGHMEM work on 32-bit MIPS ports?

[David VomLehn <dvomlehn@cisco.com>]

> On Wed, 20 Feb 2008, David VomLehn wrote:
>
> > Hmm, this is not good. I've got a MIPS 24Kc processor with a very
> > awkward memory layout. Any hints?
>
>  What does it mean "very awkward"?  What sort of problems do you have 
> that you are trying to solve?
>
>   Maciej
Specifically, we have two banks of memory. The first starts at 
0x10000000, which is no big deal (other than wasting the page map 
entries for the first chunk of memory). The second starts at 0x60000000, so:

   1. We have to access it with high memory, and
   2. There is a huge section of unused page map entries.

As it turns out, it is starting to look like we're making progress with 
the problem with high memory: In __flush_dcache_page, nothing is done if 
PageHighMem() returns true. Not surprisingly, this leads to Bad 
Things(tm). What we are working through now is making sure that we 
understand exactly what *should* be happening.

-- 
David VomLehn, dvomlehn@cisco.com
The opinions expressed herein are likely mine, but might not be my employer's...