ath10k and QCA3977 - random transfer rate losses

Fri Feb 12 12:30:36 PST 2016

Hello,

I bought a new laptop from ASUS, Product Name E205SA and installed Arch Linux. Unfortunately, the included WLAN chipset from Qualcomm  (QCA 9377) doesn't seem to work well with Linux. Beside of being recognized, the driver/device functions normally for the first minutes after boot, but then the transfer rate is suddenly lowering from around 700 kbs to 200 kbs and less, making Internet unusable. After a while, it's recovering a bit but it seems to be random (like it's trying to sleep/power save mode?). This behavior occures for my home network as well as at my university's network. As wifi access wasn't a issue with the Windows 10 OEM installation, I guess that this might a driver/firmware/configuration problem. 

dmesg indicates
[   13.401917] ath: EEPROM regdomain: 0x6a
[   13.403870] ath: EEPROM indicates we should expect a direct regpair map
[   13.405919] ath: Country alpha2 being used: 00
[   13.407837] ath: Regpair used: 0x6a
and
[   11.267403] ath10k_pci 0000:02:00.0: pci irq msi interrupts 1 irq_mode 0 reset_mode 0
[   11.500220] ath10k_pci 0000:02:00.0: Direct firmware load for ath10k/cal-pci-0000:02:00.0.bin failed with error -2
[   11.583900] ath10k_pci 0000:02:00.0: Direct firmware load for ath10k/QCA9377/hw1.0/board-2.bin failed with error -2
[   13.394121] ath10k_pci 0000:02:00.0: qca9377 hw1.0 (0x05020000, 0x003820ff sub 1a3b:2231) fw WLAN.TF.1.0-00267-1 fwapi 5 bdapi 1 htt-ver 3.1 wmi-op 4 htt-op 3 cal otp max-sta 32 raw 0 hwcrypto 1 features ignore-otp
[   13.398452] ath10k_pci 0000:02:00.0: debug 1 debugfs 1 tracing 0 dfs 0 testmode 0
[   13.422666] ath10k_pci 0000:02:00.0 wlp2s0: renamed from wlan0

The firmware files were downloaded from the git repository <https://github.com/kvalo/ath10k-firmware>. In addition to that iwconfig gives me a high number of invalid miscs. I use kernel 4.4.1 (Arch Linux). ethtools -i wlp2s0 prints out 

driver: ath10k_pci
version: 4.4.1-2-ARCH
firmware-version: WLAN.TF.1.0-00267-1
expansion-rom-version: 
bus-info: 0000:02:00.0
supports-statistics: yes
supports-test: no
supports-eeprom-access: no
supports-register-dump: no
supports-priv-flags: no

and lspci provides

02:00.0 Network controller: Qualcomm Atheros Device 0042 (rev 30)
	Subsystem: AzureWave Device 2231
	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 315
	Region 0: Memory at 81000000 (64-bit, non-prefetchable) [size=2M]
	Capabilities: [40] Power Management version 3
		Flags: PMEClk- DSI- D1- D2- AuxCurrent=375mA PME(D0+,D1-,D2-,D3hot+,D3cold+)
		Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME-
	Capabilities: [50] MSI: Enable+ Count=1/8 Maskable+ 64bit-
		Address: fee0f00c  Data: 4163
		Masking: fffffffe  Pending: 00000000
	Capabilities: [70] Express (v2) Endpoint, MSI 00
		DevCap:	MaxPayload 256 bytes, PhantFunc 0, Latency L0s unlimited, 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, Exit Latency L0s <4us, L1 <64us
			ClockPM+ Surprise- LLActRep- BwNot- ASPMOptComp+
		LnkCtl:	ASPM L0s L1 Enabled; RCB 64 bytes Disabled- CommClk+
			ExtSynch- ClockPM+ AutWidDis- BWInt- AutBWInt-
		LnkSta:	Speed 2.5GT/s, Width x1, TrErr- Train- SlotClk+ DLActive- BWMgmt- ABWMgmt-
		DevCap2: Completion Timeout: Not Supported, TimeoutDis+, LTR+, OBFF Via message
		DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis-, LTR+, OBFF Disabled
		LnkCtl2: Target Link Speed: 2.5GT/s, EnterCompliance- SpeedDis-
			 Transmit Margin: Normal Operating Range, EnterModifiedCompliance- ComplianceSOS-
			 Compliance De-emphasis: -6dB
		LnkSta2: Current De-emphasis Level: -6dB, EqualizationComplete-, EqualizationPhase1-
			 EqualizationPhase2-, EqualizationPhase3-, LinkEqualizationRequest-
	Capabilities: [100 v2] Advanced Error Reporting
		UESta:	DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt- RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
		UEMsk:	DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt- RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
		UESvrt:	DLP+ SDES+ TLP- FCP+ CmpltTO- CmpltAbrt- UnxCmplt- RxOF+ MalfTLP+ ECRC- UnsupReq- ACSViol-
		CESta:	RxErr- BadTLP- BadDLLP- Rollover- Timeout- NonFatalErr-
		CEMsk:	RxErr- BadTLP- BadDLLP- Rollover- Timeout- NonFatalErr+
		AERCap:	First Error Pointer: 00, GenCap- CGenEn- ChkCap- ChkEn-
	Capabilities: [148 v1] Virtual Channel
		Caps:	LPEVC=0 RefClk=100ns PATEntryBits=1
		Arb:	Fixed- WRR32- WRR64- WRR128-
		Ctrl:	ArbSelect=Fixed
		Status:	InProgress-
		VC0:	Caps:	PATOffset=00 MaxTimeSlots=1 RejSnoopTrans-
			Arb:	Fixed- WRR32- WRR64- WRR128- TWRR128- WRR256-
			Ctrl:	Enable+ ID=0 ArbSelect=Fixed TC/VC=ff
			Status:	NegoPending- InProgress-
	Capabilities: [168 v1] Device Serial Number 00-00-00-00-00-00-00-00
	Capabilities: [178 v1] Latency Tolerance Reporting
		Max snoop latency: 15360ns
		Max no snoop latency: 15360ns
	Capabilities: [180 v1] L1 PM Substates
		L1SubCap: PCI-PM_L1.2+ PCI-PM_L1.1+ ASPM_L1.2+ ASPM_L1.1+ L1_PM_Substates+
			  PortCommonModeRestoreTime=50us PortTPowerOnTime=10us
	Kernel driver in use: ath10k_pci
	Kernel modules: ath10k_pci

Could anyone give me a hint how I might fix this? Any help is greatly appreciated.

Regards,
Tobias