* So, is there support for IDE devices that have no IRQ?
@ 2004-03-24 23:29 Marc Singer
2004-03-25 0:04 ` Bartlomiej Zolnierkiewicz
0 siblings, 1 reply; 6+ messages in thread
From: Marc Singer @ 2004-03-24 23:29 UTC (permalink / raw)
To: linux-ide
I'm getting the impression that there isn't. I've got a system with
compact flash and no interrupt line to the device. Setting the
hwif->irq value to -1 causes the kernel to crash, though there is a
IDE_NO_IRQ constant. I'm good to make this work, but I want to make
sure that I'm heading in a reasonable direction.
The thing that's confusing me is that I'm not getting an ide0 device
even though I can see the code probing for drives.
Cheers.
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: So, is there support for IDE devices that have no IRQ?
2004-03-24 23:29 So, is there support for IDE devices that have no IRQ? Marc Singer
@ 2004-03-25 0:04 ` Bartlomiej Zolnierkiewicz
2004-03-25 1:44 ` Marc Singer
0 siblings, 1 reply; 6+ messages in thread
From: Bartlomiej Zolnierkiewicz @ 2004-03-25 0:04 UTC (permalink / raw)
To: Marc Singer; +Cc: linux-ide
Probing code uses polling but actual NODATA/PIO/DMA handlers require IRQ
so it needs much effort to make it work.
Cheers,
Bartlomiej
On Thursday 25 of March 2004 00:29, Marc Singer wrote:
> I'm getting the impression that there isn't. I've got a system with
> compact flash and no interrupt line to the device. Setting the
> hwif->irq value to -1 causes the kernel to crash, though there is a
> IDE_NO_IRQ constant. I'm good to make this work, but I want to make
> sure that I'm heading in a reasonable direction.
>
> The thing that's confusing me is that I'm not getting an ide0 device
> even though I can see the code probing for drives.
>
> Cheers.
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: So, is there support for IDE devices that have no IRQ?
2004-03-25 0:04 ` Bartlomiej Zolnierkiewicz
@ 2004-03-25 1:44 ` Marc Singer
2004-03-25 2:23 ` Bartlomiej Zolnierkiewicz
2004-03-25 3:21 ` Benjamin Herrenschmidt
0 siblings, 2 replies; 6+ messages in thread
From: Marc Singer @ 2004-03-25 1:44 UTC (permalink / raw)
To: Bartlomiej Zolnierkiewicz; +Cc: linux-ide
On Thu, Mar 25, 2004 at 01:04:10AM +0100, Bartlomiej Zolnierkiewicz wrote:
>
> Probing code uses polling but actual NODATA/PIO/DMA handlers require IRQ
> so it needs much effort to make it work.
Well, I'm thinking that I can emulate the irq by using a timer. A bad
hack, but it ought to work as long as I can get the timing correct.
This is for a compact flash interface.
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: So, is there support for IDE devices that have no IRQ?
2004-03-25 1:44 ` Marc Singer
@ 2004-03-25 2:23 ` Bartlomiej Zolnierkiewicz
2004-03-25 2:25 ` Marc Singer
2004-03-25 3:21 ` Benjamin Herrenschmidt
1 sibling, 1 reply; 6+ messages in thread
From: Bartlomiej Zolnierkiewicz @ 2004-03-25 2:23 UTC (permalink / raw)
To: Marc Singer; +Cc: linux-ide
On Thursday 25 of March 2004 02:44, Marc Singer wrote:
> On Thu, Mar 25, 2004 at 01:04:10AM +0100, Bartlomiej Zolnierkiewicz wrote:
> > Probing code uses polling but actual NODATA/PIO/DMA handlers require IRQ
> > so it needs much effort to make it work.
>
> Well, I'm thinking that I can emulate the irq by using a timer. A bad
> hack, but it ought to work as long as I can get the timing correct.
> This is for a compact flash interface.
Sigh, proper fix is to convert NODATA/PIO handlers to use polling.
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: So, is there support for IDE devices that have no IRQ?
2004-03-25 2:23 ` Bartlomiej Zolnierkiewicz
@ 2004-03-25 2:25 ` Marc Singer
0 siblings, 0 replies; 6+ messages in thread
From: Marc Singer @ 2004-03-25 2:25 UTC (permalink / raw)
To: Bartlomiej Zolnierkiewicz; +Cc: linux-ide
On Thu, Mar 25, 2004 at 03:23:44AM +0100, Bartlomiej Zolnierkiewicz wrote:
> On Thursday 25 of March 2004 02:44, Marc Singer wrote:
> > On Thu, Mar 25, 2004 at 01:04:10AM +0100, Bartlomiej Zolnierkiewicz wrote:
> > > Probing code uses polling but actual NODATA/PIO/DMA handlers require IRQ
> > > so it needs much effort to make it work.
> >
> > Well, I'm thinking that I can emulate the irq by using a timer. A bad
> > hack, but it ought to work as long as I can get the timing correct.
> > This is for a compact flash interface.
>
> Sigh, proper fix is to convert NODATA/PIO handlers to use polling.
Of course, I'd rather do that. 8-)
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: So, is there support for IDE devices that have no IRQ?
2004-03-25 1:44 ` Marc Singer
2004-03-25 2:23 ` Bartlomiej Zolnierkiewicz
@ 2004-03-25 3:21 ` Benjamin Herrenschmidt
1 sibling, 0 replies; 6+ messages in thread
From: Benjamin Herrenschmidt @ 2004-03-25 3:21 UTC (permalink / raw)
To: Marc Singer; +Cc: Bartlomiej Zolnierkiewicz, linux-ide
On Thu, 2004-03-25 at 12:44, Marc Singer wrote:
> On Thu, Mar 25, 2004 at 01:04:10AM +0100, Bartlomiej Zolnierkiewicz wrote:
> >
> > Probing code uses polling but actual NODATA/PIO/DMA handlers require IRQ
> > so it needs much effort to make it work.
>
> Well, I'm thinking that I can emulate the irq by using a timer. A bad
> hack, but it ought to work as long as I can get the timing correct.
> This is for a compact flash interface.
Well, before doing such a big pile of shit, you should think seriously
about making the HW person (provided it's not you) regret deeply his
mistake :) Seriously, not wiring the IRQ line is _DUMB_ at best
Ben.
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2004-03-25 3:21 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
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2004-03-24 23:29 So, is there support for IDE devices that have no IRQ? Marc Singer
2004-03-25 0:04 ` Bartlomiej Zolnierkiewicz
2004-03-25 1:44 ` Marc Singer
2004-03-25 2:23 ` Bartlomiej Zolnierkiewicz
2004-03-25 2:25 ` Marc Singer
2004-03-25 3:21 ` Benjamin Herrenschmidt
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