I've got an AR5418 chip in a T60 laptop connecting to a Dlink DIR-655 Hardware version A2, Firmware version 1.11. As I understand it, these both use the AR5008 series chip sets.
Using the driver in svn3401, I am consistenly able to get ~2MB/s up and down, however going to svn3545 and higher (including the latest svn3766) this is cut down to about 600KB/s. My tests consist of using scp to transfer a single large tar file to and from a machine connected to one of the wired Ethernet ports on the router. I'm connecting using WPA2-Personal with CCMP encryption.
Please let me know if there is any additional debugging I should do.
This is my card according to lspci:
03:00.0 Network controller: Atheros Communications Inc. AR5418 802.11abgn Wireless PCI Express Adapter (rev 01)
Subsystem: Atheros Communications Inc. Device 0033
Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR+ FastB2B- DisINTx-
Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
Latency: 0, Cache Line Size: 64 bytes
Interrupt: pin A routed to IRQ 17
Region 0: Memory at edf00000 (64-bit, non-prefetchable) [size=64K]
Capabilities: [40] Power Management version 2
Flags: PMEClk- DSI- D1+ D2- AuxCurrent=375mA PME(D0+,D1+,D2-,D3hot+,D3cold-)
Status: D0 PME-Enable- DSel=0 DScale=0 PME-
Capabilities: [50] Message Signalled Interrupts: Mask- 64bit- Queue=0/0 Enable-
Address: 00000000 Data: 0000
Capabilities: [60] Express (v1) Legacy Endpoint, MSI 00
DevCap: MaxPayload 128 bytes, PhantFunc 0, Latency L0s <512ns, L1 <64us
ExtTag- AttnBtn- AttnInd- PwrInd- RBE- FLReset-
DevCtl: Report errors: Correctable- Non-Fatal- Fatal- Unsupported-
RlxdOrd+ ExtTag- PhantFunc- AuxPwr- NoSnoop-
MaxPayload 128 bytes, MaxReadReq 512 bytes
DevSta: CorrErr- UncorrErr+ FatalErr- UnsuppReq+ AuxPwr- TransPend-
LnkCap: Port #0, Speed 2.5GT/s, Width x1, ASPM L0s L1, Latency L0 <512ns, L1 <64us
ClockPM- Suprise- LLActRep- BwNot-
LnkCtl: ASPM L0s L1 Enabled; RCB 128 bytes Disabled- Retrain- CommClk+
ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
LnkSta: Speed 2.5GT/s, Width x1, TrErr- Train- SlotClk+ DLActive- BWMgmt- ABWMgmt-
Capabilities: [90] MSI-X: Enable- Mask- TabSize=1
Vector table: BAR=0 offset=00000000
PBA: BAR=0 offset=00000000
Capabilities: [100] Advanced Error Reporting <?>
Capabilities: [140] Virtual Channel <?>
Kernel driver in use: ath_pci
Kernel modules: ath_pci