SV: SV: New invalidate/clean/flush_dcache functions

Segher Boessenkool segher at koffie.nl
Sat Dec 28 15:01:46 EST 2002


Joakim Tjernlund wrote:
>
> In my typical example I need to invalidate a buffer before I give it to
> the
> CPM to be used as a receive buffer. Once given to the CPM there must be
> no more writes to that buffer memory. When the CPM has received data
> and written the data into the buffer and hands it over to the CPU
> (usally via an interrupt) the next read from the CPU must access it from
> the memory.  Does the above require a sync?

Probably not, I don't know much about the CPM though (and I assume this
is a system without any extra cpu's).

> Does it take some time before a invalidate is completed?

Depends on your cpu; I don't know the details for your cpu.  Check your
manuals :)


Segher


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