Comment 32 for bug 369005

There is a hardware bug on some adapters, such as Atheros 5007EG on Acer Aspire One netbook. Connection may drop suddenly or work instable, dmesg shows: ath5k: unsupported jumbo. The reason is a result of poor hardware ASPM support. It is a hardware bug that is worked around in windows driver by disabling PCIE ASPM L0S.

There's a solution - turn ASPM L0S off manually for this device.

1. Download enable-aspm
http://kernel.org/pub/linux/kernel/people/mcgrof/aspm/enable-aspm

2. Get your root complex:

$ lspci -tv
0000:00
...
+-1c.2-[0000:03]----00.0 Atheros Communications Inc. AR5001 Wireless Network
Adapter
...
So root complex is 00:1c.2

3. Get your endpoint:

$ lspci
...
03:00.0 Ethernet controller: Atheros Communications Inc. AR5001 Wireless Network
Adapter (rev 01)
...
The endpoint is 03:00.0

4. Now you need to edit your enable-aspm

# You just need to modify these three values:

ROOT_COMPLEX="00:1c.2"
ENDPOINT="03:00.0"

ASPM_SETTING=2
5. Now executing:

vo-one <at> acerone:~$ sudo bash enable-aspm
[sudo] password for vo-one:
Root complex:
00:1c.2 PCI bridge: Intel Corporation N10/ICH 7 Family PCI Express Port 3 (rev
02)
0x50 : 0x43 --> 0x42 ... [SUCCESS]]
L1 only

Endpoint:
03:00.0 Ethernet controller: Atheros Communications Inc. AR5001 Wireless Network
Adapter (rev 01)
0x70 : 0x4B --> 0x4A ... [SUCCESS]]
L1 only
6. Making the script executed at system startup:

sudo chmod +x enable-aspm
sudo cp enable-aspm /usr/bin
Then add a line "enable-aspm" into your /etc/rc.conf before the line "exit 0;" to make the script executed at the system startup.