help

[Lennart Sorensen]

On Wed, Jan 30, 2008 at 08:50:42PM -0500, chris-n/jUll39koHNgV/OU4+dkA at public.gmane.org wrote:
> Looks like it has its own IRQ: 
> 
> root at cpc:~# cat /proc/interrupts
>          CPU0
> 0:        292   IO-APIC-edge      timer
> 1:      12181   IO-APIC-edge      i8042
> 6:          5   IO-APIC-edge      floppy
> 7:          0   IO-APIC-edge      parport0
> 8:          3   IO-APIC-edge      rtc
> 9:          1   IO-APIC-fasteoi   acpi
> 12:     471474   IO-APIC-edge      i8042
> 14:     158029   IO-APIC-edge      libata
> 15:     134739   IO-APIC-edge      libata
> 16:      70018   IO-APIC-fasteoi   uhci_hcd:usb1
> 17:      29008   IO-APIC-fasteoi   eth0
> 18:          3   IO-APIC-fasteoi   ohci1394
> 19:      24487   IO-APIC-fasteoi   EMU10K1
> 20:          0   IO-APIC-fasteoi   Intel 82801BA-ICH2

The IRQs above 15 are probably APIC interrupts which most newer systems
use which helps reduce the number of shared IRQs.  Quite handy really.

I have seen systems where the IRQs count up by 4 or 8 at a time.  I am
sure they have some mapping to reality but in linux they are really just
mapped to some physical interrupt line somewhere.  For example here is
my new machine:

test64:~# cat /proc/interrupts
           CPU0       CPU1       CPU2       CPU3
  0:    4147451    4148059    4148003    4149140   IO-APIC-edge      timer
  1:       3594       3555       3579       3511   IO-APIC-edge      i8042
  8:   48379457   48381202   48380887   48379611   IO-APIC-edge      rtc
  9:          0          0          0          0   IO-APIC-fasteoi   acpi
 16:     372790     372531     372169     372333   IO-APIC-fasteoi   uhci_hcd:usb1, ahci, firewire_ohci, nvidia
 17:     545079     545118     545336     545302   IO-APIC-fasteoi   ide0
 18:          1          0          1          0   IO-APIC-fasteoi   uhci_hcd:usb3, ehci_hcd:usb4, uhci_hcd:usb7
 19:          0          0          0          0   IO-APIC-fasteoi   uhci_hcd:usb6
 21:       2251       2131       2131       2198   IO-APIC-fasteoi   uhci_hcd:usb2
 22:       2891       2797       2787       2869   IO-APIC-fasteoi   libata, libata, HDA Intel
 23:          0          0          0          0   IO-APIC-fasteoi   uhci_hcd:usb5, ehci_hcd:usb8
1275:     643416     641424     641924     641854   PCI-MSI-edge      eth0
NMI:          0          0          0          0
LOC:   16592025   16592005   16591893   16591877
ERR:          0

I like IRQ 1275.  Apparently the ethernet on this machine now uses an
MSI IRQ which is a new type of IRQ that is per PCI device and hence
never needs sharing.  The hope is all future designs will head that way
since shared IRQs are less efficient (you have to make each driver that
has a device on that IRQ check if its device causes the IRQ, while MSI
means there is no sharing and hence you always go directly to the right
driver and never waste any time checking for the actual source of the
IRQ).

> [   47.313984] emu1010: Special config.
> [   47.314103] emu1010: EMU_HANA_ID=0x7f
> [   47.486647] 
> /build/buildd/linux-source-2.6.22-2.6.22/drivers/usb/class/usblp.c: usblp0: 
> USB Bidirectional printer dev 2 if 1 alt 0 proto 2 vid 0x03F0 pid 0x4811
> [   47.486709] usbcore: registered new interface driver usblp
> [   47.486720] 
> /build/buildd/linux-source-2.6.22-2.6.22/drivers/usb/class/usblp.c: v0.13: 
> USB Printer Device Class driver
> [   48.106570] firmware size=0x133a4
> [   50.500129] eth0: no IPv6 routers present
> [   51.196134] emu1010: Hana Firmware loaded

That's a good sign.  What changed since the time it said it couldn't
load it?

> [   51.196185] Hana ver:3.4
> [   51.196245] emu1010: Card options=0x1
> [   51.196272] emu1010: Card options=0x1
> [   51.196758] emu1010: Card options3=0x1
> [   51.314247] EMU outputs on
> [   51.314263] EMU inputs on 

--
Len Sorensen
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