[Prism54-users] terminal prism54 performance problems

[Paul Jakma]

Hi,

I'm experiencing severe problems (ie doesnt work) with the prism54 
driver. Setup:

APs:

2x Netgear WG602v2 with latest 3.2rc6 firmware (upgraded from 3.1rc5 
iirc, made no difference to problem). I have tried with preamble set 
to both mixed and long. The 2 APs are in multipoint-bridging mode, 
with about 86% link strength between them, one bridging the wireless 
network onto 100BaseT network. I'm using WEP128 on the wireless 
links.

I can ping flood from the 100BaseT network, over the wireless link to 
the wireless only AP with 0 packet loss:

--- 192.168.0.9 ping statistics ---
312 packets transmitted, 312 received, 0% packet loss, time 3887ms
rtt min/avg/max/mdev = 1.913/5.146/90.770/12.389 ms, pipe 8, ipg/ewma 
12.499/2.276 ms

So that link is good.

The wireless only AP provides service to a single client:

Sony Vaio PCG-C1F with built-in Ricoh RL5c475 cardbus controller
WG511 Cardbus Prism54 802.11g card
1.0.4.3 Prism54 firmware[1]
Fedora Core 2 Linux
Arjan's 2.6.8-1.521 FC kernel package

With the driver provided in the 2.6.8-1.521 kernel, which i think is 
prism54 1.2, the computer locks up after any decent amount of traffic 
(eg downloading a file from the internet, which would be limited to 
~50kB/s due to DSL, or ping -f -s 1500). The yellow light on the 
WG511 still flickers, indicating, I presume that it's still receiving 
occassional wireless traffic, however the computer is dead, other 
than the console cursor still blinking (which i think is done in 
hardware). The keyboard is completely unresponsive, num/caps lock 
dont work, not even alt+sysrq works, so presumably the prism54 is 
stuck somewhere with interrupts disabled.

If I manually eject the WG511, the PC becomes responsive again. If I 
insert the WG511 again, it will be configured by cardctl and brought 
up, when that occurs the PC will die again, irretrievably, needing a 
hard reboot.

I also tried with latest CVS. I downloaded ksrc as of about 1500GMT 
and compiled it. With this I get an almost instant panic, each time 
with EIP in wireless_spy_update(), from islpci_eth_receive() from 
do_IRQ context, with lspci_interrupt() somewhere in the call path 
between do_IRQ and islpci_eth_receive() (there'll be other interrupt 
handlers there sometimes, eg acpi or atkbd. this laptop seems to have 
nearly everything wired to irq 9 for some reason).

I have tried booting acpi=off and acpi=on. No difference. Note that I 
boot with pci=usepirqmask, without that the prism54 wont work at all.

Suggestions/debugging advice would be appreciated, and I'd be glad to 
provide any more specific information that is desired.

1. I'd love to hear from someone with newer firmware. I tried running 
Netgear's latest Windows driver update under WiNE to try extract 
their firmware, but it didnt work.

regards,
-- 
Paul Jakma	paul at clubi.ie	paul at jakma.org	Key ID: 64A2FF6A
Fortune:
Chaos is King and Magic is loose in the world.