Boot IRQ issue on Intel C602J (Advantech ASMB-822)

Boot IRQ issue on Intel C602J (Advantech ASMB-822)

[Alexander Gerasiov]

Hello there.

We are using 3.10.74-rt79 in our system and found some problem with
Advantech ASMB-822 motherboard.

It's Intel C602J based m/b with 2 IO-APIC.

We have 2 special PCIe adapters installed. They use legacy interrupts
through APIC.

On 3.10.74 one of adapter generate only several (~10) interrupts and
then halts. As I discovered, it works ok, but no interrupts was
delivered. The same time (but after device stops receiving irqs) boot
irqs occur and irq 16 got disabled by the kernel.

I tried 3.18.25 with the same result.

Right now I'm running 4.4.1-rt4 and finally it works, but there are
still boot irqs and kernel disables IRQ 16 because of them.

So I need some ideas, how to deal with boot interrupts on this chipset.
May be to add workaround like masking boot irq together with IO-APIC
irq.

PS If someone could give a clue, what was changed in 4.4.1 from 3.18
that would be great. (As I'm not sure we could switch production system
to 4.4.1 soon, and I'd like to backport this change set to old kernel if
possible.)

-- 
Best regards,
 Alexander Gerasiov

 Contacts:
 e-mail: gq@cs.msu.su  Homepage: http://gerasiov.net  Skype: gerasiov
 PGP fingerprint: 04B5 9D90 DF7C C2AB CD49  BAEA CA87 E9E8 2AAC 33F1

Re: Boot IRQ issue on Intel C602J (Advantech ASMB-822)

[Thomas Gleixner]

On Mon, 8 Feb 2016, Alexander Gerasiov wrote:
> On 3.10.74 one of adapter generate only several (~10) interrupts and
> then halts. As I discovered, it works ok, but no interrupts was
> delivered. The same time (but after device stops receiving irqs) boot
> irqs occur and irq 16 got disabled by the kernel.
> 
> I tried 3.18.25 with the same result.
> 
> Right now I'm running 4.4.1-rt4 and finally it works, but there are
> still boot irqs and kernel disables IRQ 16 because of them.

Can you please provide the output of:

# lspci -s 00:1f.0 -xxx

Thanks,

	tglx

Re: Boot IRQ issue on Intel C602J (Advantech ASMB-822)

[Alexander Gerasiov]

Hello Thomas,

On Tue, 9 Feb 2016 11:34:01 +0100 (CET)
Thomas Gleixner <tglx@linutronix.de> wrote:

> On Mon, 8 Feb 2016, Alexander Gerasiov wrote:
> > On 3.10.74 one of adapter generate only several (~10) interrupts and
> > then halts. As I discovered, it works ok, but no interrupts was
> > delivered. The same time (but after device stops receiving irqs)
> > boot irqs occur and irq 16 got disabled by the kernel.
> > 
> > I tried 3.18.25 with the same result.
> > 
> > Right now I'm running 4.4.1-rt4 and finally it works, but there are
> > still boot irqs and kernel disables IRQ 16 because of them.
> 
> Can you please provide the output of:
> 
> # lspci -s 00:1f.0 -xxx


root@mu:~# lspci -s 00:1f.0 -xxx
00:1f.0 ISA bridge: Intel Corporation C600/X79 series chipset LPC Controller (rev 06)
00: 86 80 41 1d 07 00 10 02 06 00 01 06 00 00 80 00
10: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
20: 00 00 00 00 00 00 00 00 00 00 00 00 86 80 41 1d
30: 00 00 00 00 e0 00 00 00 00 00 00 00 00 00 00 00
40: 01 04 00 00 80 00 00 00 01 05 00 00 10 00 00 00
50: f8 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
60: 8b 8a 8b 8b d0 00 00 00 87 80 80 8a f8 f0 00 00
70: 78 f0 78 f0 78 f0 78 f0 78 f0 78 f0 78 f0 78 f0
80: 10 00 0f 3f 01 0a fc 00 a1 0c 0c 00 00 00 00 00
90: 00 00 00 00 00 0f 00 00 00 00 00 00 00 00 00 00
a0: 18 0a 20 00 48 19 06 00 00 47 00 00 00 03 00 80
b0: 00 00 00 00 00 00 00 00 02 00 00 00 00 00 00 00
c0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
d0: 33 22 11 00 67 45 00 00 c0 ff 00 00 2a 00 00 00
e0: 09 00 0c 10 00 00 00 00 91 02 64 0c 00 00 00 00
f0: 01 c0 d1 fe 00 00 00 00 87 0f 08 08 00 00 00 00


-- 
Best regards,
 Alexander Gerasiov

 Contacts:
 e-mail: gq@cs.msu.su  Homepage: http://gerasiov.net  Skype: gerasiov
 PGP fingerprint: 04B5 9D90 DF7C C2AB CD49  BAEA CA87 E9E8 2AAC 33F1