On Fri, 12 Sep 2008 19:34:06 +0400, Sergei Shtylyov <sshtylyov@ru.mvista.com>
wrote:
> >> You shouldn't fake the BMDMA interrupt. If it's not there, it's not
> >>there. Or does this actually happen?
>
> > IIRC, Yes.
>
> Hum, let me think... worth printing a message if this happens.
It might be. I'll try it.
> >>>+ /*
> >>>+ * If only one of XFERINT and HOST was asserted, mask
> >>>+ * this interrupt and wait for an another one. Note
>
> >> This comment somewhat contradicts the code which returns 1 if only
> >>HOST interupt is asserted if ERR is set.
>
> Which is not its business to test. I think you should remove that above
> check -- if there's INTRQ asserted, then it's asserted. I wonder if BMIDE
> interrupt bit gets set in that case (suspecting it's not)...
Well, let me explain a bit. The datasheed say I should wait _both_
XFERINT and HOST interrupt. So, if only one of them was asserted, I
mask it and wait another one. But on the error case, only HOST was
asserted and XFERINT was never asserted. Then I could not exit from
"waiting another one" state, until timeout.
> >>>+ pr_debug("%s: weired interrupt status. "
> >>>
>
> >> Weird.
>
> > Sure. But it can happen IIRC...
>
> I meant the typo. :-)
Oh, thanks!
> >>>+ __ide_flush_dcache_range((unsigned long)addr, size);
>
> >> Why is this needed BTW?
>
> > Do you mean __ide_flush_dcache_range? This is needed to avoid cache
> > inconsistency on PIO drive. PIO transfer only writes to cache but
> > upper layers expects the data is in main memory.
>
> Hum, then I wonder why it's MIPS specific...
SPARC also have it. And there were some discussions for ARM IIRC.
> >>>+ .read_sff_dma_status = tx4939ide_read_sff_dma_status,
>
> >> Hum, it should be re-defined in both LE and BE mode (but actually not
> >>called anyway).
>
> > What do you mean? Please elaborate?
>
> I mean that in LE mode you're using ide_read_sff_dma_status() but not
> setting hwif->dma_base, so it won't work. But since it shouldn't be called in
> this driver's case, this doesn't hurt.
Yes, I see, thanks.
---
Atsushi Nemoto
|