pci_alloc_irq_vectors fails ENOSPC for XPS 13 9310

[Thomas Krause]

Hello,

some variants of Dell XPS 13 9310 model have a QCA6390 device and I was 
trying to make it work using the  ath.git master branch (tag 
ath-202010011934).

Unfortunatly, I get the following error messages when loading the module:

> [  672.277726] ath11k_pci 0000:56:00.0: WARNING: ath11k PCI support is 
> experimental!
> [  672.277925] ath11k_pci 0000:56:00.0: BAR 0: assigned [mem 
> 0x8c300000-0x8c3fffff 64bit]
> [  672.278020] ath11k_pci 0000:56:00.0: failed to get 32 MSI vectors, 
> only -28 available
> [  672.278024] ath11k_pci 0000:56:00.0: failed to enable msi: -28
> [  672.278144] ath11k_pci: probe of 0000:56:00.0 failed with error -28

-28 seems to reference ENOSPC, which seems to be related to the minimum 
number of vectors not beeing available. lspci output is

> 56:00.0 Network controller: Qualcomm Device 1101 (rev 01)
>     Subsystem: Rivet Networks Device a501
>     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-
>     Region 0: Memory at 8c300000 (64-bit, non-prefetchable) [size=1M]
>     Capabilities: [40] Power Management version 3
>         Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA 
> PME(D0+,D1-,D2-,D3hot+,D3cold+)
>         Status: D0 NoSoftRst+ PME-Enable- DSel=0 DScale=0 PME-
>     Capabilities: [50] MSI: Enable- Count=1/32 Maskable+ 64bit-
>         Address: fee01004  Data: 40ef
>         Masking: 00000000  Pending: 00000000
>     Capabilities: [70] Express (v2) Endpoint, MSI 00
>         DevCap:    MaxPayload 128 bytes, PhantFunc 0, Latency L0s 
> unlimited, L1 unlimited
>             ExtTag- AttnBtn- AttnInd- PwrInd- RBE+ FLReset- 
> SlotPowerLimit 10.000W
>         DevCtl:    CorrErr- NonFatalErr- FatalErr- UnsupReq-
>             RlxdOrd+ ExtTag- PhantFunc- AuxPwr- NoSnoop+
>             MaxPayload 128 bytes, MaxReadReq 512 bytes
>         DevSta:    CorrErr+ NonFatalErr- FatalErr- UnsupReq+ AuxPwr+ 
> TransPend-
>         LnkCap:    Port #0, Speed 8GT/s, Width x1, ASPM L0s L1, Exit 
> Latency L0s <1us, L1 <64us
>             ClockPM- Surprise- LLActRep- BwNot- ASPMOptComp+
>         LnkCtl:    ASPM L1 Enabled; RCB 64 bytes Disabled- CommClk+
>             ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
>         LnkSta:    Speed 5GT/s (downgraded), Width x1 (ok)
>             TrErr- Train- SlotClk+ DLActive- BWMgmt- ABWMgmt-
>         DevCap2: Completion Timeout: Range ABCD, TimeoutDis+, 
> NROPrPrP-, LTR+
>              10BitTagComp-, 10BitTagReq-, OBFF Not Supported, ExtFmt-, 
> EETLPPrefix-
>              EmergencyPowerReduction Not Supported, 
> EmergencyPowerReductionInit-
>              FRS-, TPHComp+, ExtTPHComp-
>              AtomicOpsCap: 32bit- 64bit- 128bitCAS-
>         DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis-, LTR+, 
> OBFF Disabled
>              AtomicOpsCtl: ReqEn-
>         LnkCtl2: Target Link Speed: 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- 
> AdvNonFatalErr+
>         CEMsk:    RxErr- BadTLP- BadDLLP- Rollover- Timeout- 
> AdvNonFatalErr+
>         AERCap:    First Error Pointer: 00, ECRCGenCap+ ECRCGenEn- 
> ECRCChkCap+ ECRCChkEn-
>             MultHdrRecCap- MultHdrRecEn- TLPPfxPres- HdrLogCap-
>         HeaderLog: 00000000 00000000 00000000 00000000
>     Capabilities: [148 v1] Secondary PCI Express
>         LnkCtl3: LnkEquIntrruptEn-, PerformEqu-
>         LaneErrStat: 0
>     Capabilities: [158 v1] Transaction Processing Hints
>         No steering table available
>     Capabilities: [1e4 v1] Latency Tolerance Reporting
>         Max snoop latency: 3145728ns
>         Max no snoop latency: 3145728ns
>     Capabilities: [1ec v1] L1 PM Substates
>         L1SubCap: PCI-PM_L1.2+ PCI-PM_L1.1+ ASPM_L1.2+ ASPM_L1.1+ 
> L1_PM_Substates+
>               PortCommonModeRestoreTime=70us PortTPowerOnTime=0us
>         L1SubCtl1: PCI-PM_L1.2+ PCI-PM_L1.1+ ASPM_L1.2+ ASPM_L1.1+
>                T_CommonMode=0us LTR1.2_Threshold=81920ns
>         L1SubCtl2: T_PwrOn=44us
>     Kernel modules: ath11k_pci
It there anything in my side I can to to fix the vector allocation or is 
the XPS 13 9310 just not supported? Bluetooth works with this kernel 
version, only Wifi fails.

Best,

Thomas