Re: [parisc-linux] 32bit parisc kernel 2.6.1 and pcmcia

[Helge Deller <deller@gmx.de>]

On Monday 19 January 2004 06:59, Grant Grundler wrote:
> On Sun, Jan 18, 2004 at 08:59:34PM +0100, Helge Deller wrote:
> > Dino fff80000: stuck interrupt 4
> 
> The message means the IRQ was asserted and whatever handlers
> are registered for that IRQ did not clear the IRQ level.
> 
> > Any ideas why I get the above "Dino fff80000: stuck interrupt 4" message ?
> > It seems further interrupts are not delivered to serial_cs....
> 
> When the PCI IRQ line is asserted, dino will only generate one
> interrupt to the CPU. CPU needs to read DINO_ILR and verify the IRQ
> has been de-asserted after the interrupt handler has been called.
> If PCI IRQ line is still asserted, we first assume several devices
> share the line and call the interrupt handlers again (goto ilr_again).
> If the PCI IRQ line is still asserted after testing ILR several times,
> (well, 100 times to be exact - see ilr_loop) , then we assume a HW defect.

Yes, that's exactly what I see:
rdi:~# cat /proc/interrupts
           CPU00
 98:        100  Dino parisc8:0  yenta
 99:          0  Dino parisc8:0  yenta

> We driver writers don't like to admit something didn't register for
> the proper interrupt. But that is likely the case here and explains
> the message and only one interrupt.
> 
> I'd be curious if both sockets report the same IRQ (4) when
> inserting the PCMCIA card.

Yes, I get this "Dino fff80000: stuck interrupt 4"  when inserting the 
card in any of the two slots.

> BTW, since PARISC doesn't tolerate accessing invalid MMIO addresses 
> like x86 does, it wouldn't surprise me if you see HPMC's during
> PCMCIA device removal/eject operations. I suspect (but don't know
> for sure) that card eject on x86 only works becuase x86
> returns garbage (-1 or 0 or something) for reads to non-responding
> address spaces.

Happend not yet :-)
Let's see, when the driver tries to access the card....

Thanks for the explanation,
Helge