Re: Missing cache flush.

Vipin Malik
2001-06-05T14:16:27Z

Bjorn Wesen wrote:

>
> I'd agree that to be really certain, a "flush_dcache()" function
> should be implemented and used when an erase finishes. Like David Miller
> wrote somewhere in the thread, one way is to use your knowledge of the
> arch's cache and do suitable dummy accesses to flush it, if there is no
> explicit command to do it. But that's just up to the arch coders..
>

Here's a stupid question: Are there any processors out there that have a cache
but no explicit cache-flush command?

If not (i.e. no such "funny" processors), then what's wrong with the arch
dependent include through a define to execute the
arch specific asm command?

The only issue (besides knowing the cache size at run time) that I can think
about the "dummy" eviction scheme is that you now need to xfer potentially 3
times the cache
size data to and from memory:

#1. The dummy read
#2. The eviction of the entire cache data being evicted
#3. The refilling of the cache with good data again, as the dummy data cannot
really represent anything useful.

Is my thinking here completely non coherent with others? ;)

Vipin