At Wed, 11 Sep 2002 00:03:09 +0200,
Emmanuel Dreyfus wrote:
> The following patch introduces two kernel threads to take care of reading data
> from the SSP. What's cool is that we don't waste CPU when we have to wait: we
> sleep instead.

Nice work!

> The interupt overhead shown by top drops to nearly zero, but I'm still not very
> satisfied with the way the system dehaves when I'm dragging a window in
> windowmaker (solid dragging enabled). But maybe it's just that the machine does
> not have enough horsepower to cope? 

IIRC, jornada720's framebuffer is in SED1356, and it is connected to
SA1110 with a relatively slow 16-bit width bus.

> I think the kernel thread for the touchpanel is probably worth it, since my last
> patch produced a lot of interrupt overhead, and this one nearly nothing. On the
> other hand, I wonder what to do with the keyboard kernel thread. We don't win
> that much with it, as far as I can tell.

Sorry for my ignorance of kernel thread.  Do the keyboard read and
the touchpanel read run exclusively?  How can we avoid multiple
entries to j720ssp_readwrite()?

--
IWAMOTO Toshihiro