13 Oct
2007
13 Oct
'07
8:59 a.m.
It's probably hardwired and dependent on the mainboard but I
thought I'd ask this anyway, just in case someone has an idea.
I notice Chuckks' /proc/interupts is like this below whereas
my Abit AN-M2 (nForce4) setup follows... is there anyway I can
manipulate my interupts so the USB devices line up on a single
IRQ like Chuckks ?
CPU0
0: 7451384 IO-APIC-edge timer
1: 16910 IO-APIC-edge i8042
8: 0 IO-APIC-edge rtc
12: 91809 IO-APIC-edge i8042
14: 55194 IO-APIC-edge ide0
16: 17785 IO-APIC-fasteoi eth1, HDA Intel
17: 124946 IO-APIC-fasteoi bcm43xx
19: 41988 IO-APIC-fasteoi ohci_hcd:usb1, ohci_hcd:usb2, ehci_hcd:usb3
20: 1 IO-APIC-fasteoi yenta, tifm_7xx1
21: 3228 IO-APIC-fasteoi acpi
CPU0 CPU1
0: 136 561 IO-APIC-edge timer
1: 49 27195 IO-APIC-edge i8042
8: 0 0 IO-APIC-edge rtc0
9: 0 30 IO-APIC-fasteoi acpi
14: 0 0 IO-APIC-edge libata
15: 0 0 IO-APIC-edge libata
16: 13465 13271804 IO-APIC-fasteoi ohci_hcd:usb1, ahci
17: 13523 11359306 IO-APIC-fasteoi ohci_hcd:usb2, eth0
18: 4 2906 IO-APIC-fasteoi ehci_hcd:usb3, HDA Intel
19: 5332 4029220 IO-APIC-fasteoi ehci_hcd:usb4, nvidia
I have a problem with distorted USB sound (Tascam US-122)
but no matter what USB port I use it is always doubled up
with another device. If I could "force" all the USB busses
onto one IRQ (or ideally ohci_hcd on one and ehci_hcd on
another), and made sure my US-122 was the only USB device,
then that might make a difference.
--markc
13 Oct
13 Oct
9:07 a.m.
On Sat, 2007-10-13 at 20:59 +1000, Mark Constable wrote:
It's probably hardwired and dependent on the
mainboard but I
thought I'd ask this anyway, just in case someone has an idea.
I notice Chuckks' /proc/interupts is like this below whereas
my Abit AN-M2 (nForce4) setup follows... is there anyway I can
manipulate my interupts so the USB devices line up on a single
IRQ like Chuckks ?
Probably not, at least not from Linux. You could look in your BIOS, but
those IRQ numbers are probably hardwired.
--ll
10:21 a.m.
G'day Mark,
You may be able to change the IRQ of USB devices if you change the IRQ
stored in the PCI configuration memory of the USB controller. Look into
the setpci command, normally part of the pciutils package. Use lsusb
and lspci to identify the controller, in particular the PCI device id.
A rediscovery of the device is needed afterwards ... which probably
means a reboot, but you could experiment with removing and re-inserting
the USB controller modules.
The BIOS may also have an option to change it. Some BIOS firmware may
simply reassing all the IRQs during initial boot ... look for an option
called configuration data.
I have a problem with distorted USB sound (Tascam
US-122)
but no matter what USB port I use it is always doubled up
with another device. If I could "force" all the USB busses
onto one IRQ (or ideally ohci_hcd on one and ehci_hcd on
another), and made sure my US-122 was the only USB device,
then that might make a difference.
But I disagree with your theory. Worth a try, sure. But on modern
systems IRQ sharing isn't generally much of a problem, unless the driver
for the other device isn't doing the right thing.
--
James Cameron mailto:quozl@us.netrek.org http://quozl.netrek.org/
6280
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participants (3)
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James Cameron -
Lars Luthman -
Mark Constable