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Re: KA48 / KA660 cache differences

2015-08-24 9:16 GMT+02:00 Felix Deichmann <m4j0rd0m0%gmail.com@localhost>:
> As suggested by the docs, our code also clears the tags' VALID flags
> before enabling the cache, but I do not understand the corresponding
> line:
>     while(cnt--) { *p++ = 0x80000000L; p++; }
> Why is only every second tag written?

Answering my own question, above code is obviously correct:
"Writes to cache tag addresses write to the cache tag indexed by bits
<09:03> of the address."
In other words: Every second longword (address) maps to an actual cache tag.

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