Can you change IRQs for pcmcia cards on T42s?

[reeman]

I have a T42 running with an add on PCMCIA Audigy 2zs. It works (sort of).

Here is a read out of the pci bus ...for the multitude of linux guys that love Thinkpads.


eric@restring:~$ lspci
00:00.0 Host bridge: Intel Corporation 82855PM Processor to I/O Controller (rev 03)
00:01.0 PCI bridge: Intel Corporation 82855PM Processor to AGP Controller (rev 03)
00:1d.0 USB Controller: Intel Corporation 82801DB/DBL/DBM (ICH4/ICH4-L/ICH4-M) USB UHCI Controller #1 (rev 01)
00:1d.1 USB Controller: Intel Corporation 82801DB/DBL/DBM (ICH4/ICH4-L/ICH4-M) USB UHCI Controller #2 (rev 01)
00:1d.2 USB Controller: Intel Corporation 82801DB/DBL/DBM (ICH4/ICH4-L/ICH4-M) USB UHCI Controller #3 (rev 01)
00:1d.7 USB Controller: Intel Corporation 82801DB/DBM (ICH4/ICH4-M) USB2 EHCI Controller (rev 01)
00:1e.0 PCI bridge: Intel Corporation 82801 Mobile PCI Bridge (rev 81)
00:1f.0 ISA bridge: Intel Corporation 82801DBM (ICH4-M) LPC Interface Bridge (rev 01)
00:1f.1 IDE interface: Intel Corporation 82801DBM (ICH4-M) IDE Controller (rev 01)
00:1f.3 SMBus: Intel Corporation 82801DB/DBL/DBM (ICH4/ICH4-L/ICH4-M) SMBus Controller (rev 01)
00:1f.5 Multimedia audio controller: Intel Corporation 82801DB/DBL/DBM (ICH4/ICH4-L/ICH4-M) AC'97 Audio Controller (rev 01)
00:1f.6 Modem: Intel Corporation 82801DB/DBL/DBM (ICH4/ICH4-L/ICH4-M) AC'97 Modem Controller (rev 01)
01:00.0 VGA compatible controller: ATI Technologies Inc Radeon Mobility M7 LW [Radeon Mobility 7500]
02:00.0 CardBus bridge: Texas Instruments PCI4520 PC card Cardbus Controller (rev 01)
02:00.1 CardBus bridge: Texas Instruments PCI4520 PC card Cardbus Controller (rev 01)
02:02.0 Ethernet controller: Atheros Communications Inc. AR5212 802.11abg NIC (rev 01)
03:00.0 Multimedia audio controller: Creative Labs SB0400 Audigy2 Value

As you can see I have cut out a few things so that the weight of IRQ shots will be as low as the bios will alow. Trouble is that having the video and usb slogging away on the same IRQ as the PCMCIA makes latency and audio recording at higher bit rate impossible without serious drops.

Has anybody had any luck changing the bios irq assignments around and how do you tell which one will isolate the pcmcia from the video or usb?

I have all my assignments set to (auto) currently and the bios makes a hash of it!

As you can see, it puts the video and just about everything else to IRQ5 even if I disable the parallel port and the serials on 3, 4, and 7.

I have at one time messed around and managed to move some of the stuff to IRQ 11 and even 3 or 4 with the serial shut down but invariably it seems that I cannot find out how to isolate the PCMCIA TI based PCI 4520 card bus controller so that it will work properly. No wonder why these sound cards are not popular! Getting them to work right is really a PITA. Any help would be greatly appreciated.

eric@restring:~$ cat /proc/interrupts
CPU0
0: 1116080 XT-PIC-XT timer
1: 3711 XT-PIC-XT i8042
2: 0 XT-PIC-XT cascade
3: 2 XT-PIC-XT
4: 3 XT-PIC-XT
5: 2747 XT-PIC-XT uhci_hcd:usb2, yenta, yenta, radeon, Intel 82801DB-ICH4, EMU10K1
6: 3 XT-PIC-XT
7: 0 XT-PIC-XT parport0
8: 0 XT-PIC-XT rtc0
9: 4500 XT-PIC-XT acpi
10: 196928 XT-PIC-XT ehci_hcd:usb1, uhci_hcd:usb3, uhci_hcd:usb4, ath
11: 3 XT-PIC-XT
12: 3131 XT-PIC-XT i8042
14: 66635 XT-PIC-XT ata_piix
15: 26477 XT-PIC-XT ata_piix
NMI: 0 Non-maskable interrupts
LOC: 0 Local timer interrupts
SPU: 0 Spurious interrupts
PMI: 0 Performance monitoring interrupts
PND: 0 Performance pending work
RES: 0 Rescheduling interrupts
CAL: 0 Function call interrupts
TLB: 0 TLB shootdowns
TRM: 0 Thermal event interrupts
THR: 0 Threshold APIC interrupts
MCE: 0 Machine check exceptions
MCP: 18 Machine check polls
ERR: 0
MIS: 0

[GomJabbar]

I don't know about changing IRQ's in the BIOS.

You can change IRQ's in Device Manager of Windows. I've done this already to enable the GPS feature of my cellular modem to work in Microsoft Streets and Trips. Instead of changing the IRQ's of the PCMCIA card drivers (Texas Instruments - I believe), change the IRQ's of the device the PCMCIA card is (i.e. modem, network adapter, sound card, etc.). You need to choose IRQ's that are not being simultaneously used by another device.

[reeman]

I don't know about changing IRQ's in the BIOS.

You can change IRQ's in Device Manager of Windows. I've done this already to enable the GPS feature of my cellular modem to work in Microsoft Streets and Trips. Instead of changing the IRQ's of the PCMCIA card drivers (Texas Instruments - I believe), change the IRQ's of the device the PCMCIA card is (i.e. modem, network adapter, sound card, etc.). You need to choose IRQ's that are not being simultaneously used by another device.

Solved problem ...


eric@restring:~$ cat /proc/interrupts
CPU0
0: 384606 XT-PIC-XT timer
1: 768 XT-PIC-XT i8042
2: 0 XT-PIC-XT cascade
4: 3 XT-PIC-XT
5: 148 XT-PIC-XT yenta, Intel 82801DB-ICH4, EMU10K1
6: 3 XT-PIC-XT
7: 0 XT-PIC-XT parport0
8: 0 XT-PIC-XT rtc0
9: 4096 XT-PIC-XT acpi
10: 89135 XT-PIC-XT uhci_hcd:usb2, uhci_hcd:usb4, yenta, radeon, ath, eth0
11: 17274 XT-PIC-XT ehci_hcd:usb1, uhci_hcd:usb3
12: 2537 XT-PIC-XT i8042
14: 40057 XT-PIC-XT ata_piix
15: 23799 XT-PIC-XT ata_piix
NMI: 0 Non-maskable interrupts
LOC: 0 Local timer interrupts
SPU: 0 Spurious interrupts
PMI: 0 Performance monitoring interrupts
PND: 0 Performance pending work
RES: 0 Rescheduling interrupts
CAL: 0 Function call interrupts
TLB: 0 TLB shootdowns
TRM: 0 Thermal event interrupts
THR: 0 Threshold APIC interrupts
MCE: 0 Machine check exceptions
MCP: 16 Machine check polls
ERR: 0
MIS: 0



Turns out the first two bios pci irq settings are:

first selection sets irq for... the bottom (yenta) card slot and onboard ac97 intel audio

second selection sets irq for... the top card slot (yenta),radeon video, usb ports 2and4, atheros wifi, and the internal ethernet card.

So you can separate out audio devices on this laptop...at first I did not think it was possible but kudos to IBM for making this possible ...if undocumented!

The rest take care of other devices and some are spurious. (perhaps they are for other add on devices that are available on other models like internal bluetooth?)

This is the key to actually changing how the thinkpad bios itself sets the irq for several combined devices. If you allow the bios to set everything automatically then everything gets lumped on to one common irq 11. Which makes sense for windows as irq sharing is how the interpreted bios info is used.

However this is not ideal because the real irqs are masked. Which is in reality just a software kludge way of dealing with core processes. This causes colliding interrupt requests at the bios level and is the main reason, along with the windows audio api, why audio pros do not use Windows.

By switching the core audio irq to 5 now the core audio api can call to the devices without being bumped. And I can temporarily shut off the onboard with a software switch so that the pcmcia card will have audio priority and can now actually do what it is capable of doing, without latency caused error or pops and drops when I move a usb attached mouse or whatever!

I should be able to get my audio latency down to a level where 24/96 realtime recording will work well.

I tried doing this with Windows XP on this laptop but it was a complete bust without changing things in the bios! There was no way to get the ASIO low latency capable high bit rate a-d recording to work.

That said I guess now that Linux helped me to figure out the order in which devices were controlled by the bios on this laptop it should work just as well with Windows.

I will most likely install windows 7 32 bit because creative has released new windows 7 asio2 capable drivers for this card and you do not have to use the stupid windows directx audio api anymore!

If there was still real time support available in Linux and the pulse audio layer was not such a dog I would stick with Linux.

So on this laptop it is possible to correct the irq assignments and it should make a killer portable audio recording device with this great little cardbus soundblaster.

I guess the reason why they did not catch on as a device was Windows and how stupid it is to setup for low latency and reliable studio grade recording. This little card is amazing it can do 24/96 analogue to digital at 104db and handle hot 1.2 Vrms line level signals from my mackie mixer!

Laptop cost me 75 bucks without OS or hdd from the government of BC surplus...then I spent 60 bucks on more ram and 50 bucks on a decent hdd...the soundblaster PCMCIA audigy2 ZS cost me 30 bucks cause the guy who sold it to me could not get it to work properly with Windows...he was a gamer and had spent over 200 bucks for this amazing card when it was new!

Now that I have it set up and running great...it does GoogleEarth 6 spinning globe in full screen in Linux without a hickup!!! which is amazing considering the onboard radeon is rather dated. So I would say all and all it should run a stripped down no aero-glass Windows 7 fairly well...heck it might even run GoogleEarth...on Windows.