66AK2E05: Keystone II - WiFi PCIe card (ath9k) - NO MSI SUPPORT - Interrupt

Ioannis Skazikis

Part Number: 66AK2E05

We are having problems with an Qualcomm-Atheros WiFi mini-pcie card that uses the ath9k driver. No irq is assigned and the wifi network device (wlan0) is not created.

Our device is a 66AK2E05 and the WiFi module is connected to the first PCI controller.

This is the relevant dmesg output:

[ 7.883684] ath9k 0000:01:00.0: enabling device (0140 -> 0142)
[ 7.883699] ath9k 0000:01:00.0: limiting MRRS to 256
[ 7.883763] ath9k 0000:01:00.0: request_irq failed
[ 7.883802] ath9k: probe of 0000:01:00.0 failed with error -22

While lspci -vv shows:

0000:00:00.0 PCI bridge: Texas Instruments Device b009 (rev 01) (prog-if 00 [Normal decode])
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 80
Region 0: Memory at <ignored> (32-bit, non-prefetchable)
Bus: primary=00, secondary=01, subordinate=ff, sec-latency=0
I/O behind bridge: [disabled]
Memory behind bridge: 50100000-501fffff [size=1M]
Prefetchable memory behind bridge: 50200000-502fffff [size=1M]
Secondary status: 66MHz- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- <SERR- <PERR-
BridgeCtl: Parity+ SERR- NoISA- VGA- VGA16- MAbort- >Reset- FastB2B-
PriDiscTmr- SecDiscTmr- DiscTmrStat- DiscTmrSERREn-
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=1/1 Maskable- 64bit+
Address: 0000000021800054 Data: 0000
Capabilities: [70] Express (v2) Root Port (Slot-), MSI 00
DevCap: MaxPayload 256 bytes, PhantFunc 0
ExtTag- RBE+
DevCtl: CorrErr+ NonFatalErr+ FatalErr+ UnsupReq+
RlxdOrd+ ExtTag- PhantFunc- AuxPwr- NoSnoop+
MaxPayload 128 bytes, MaxReadReq 256 bytes
DevSta: CorrErr- NonFatalErr- FatalErr- UnsupReq- AuxPwr- TransPend-
LnkCap: Port #0, Speed 5GT/s, Width x2, ASPM L0s, Exit Latency L0s <512ns
ClockPM- Surprise- LLActRep+ BwNot- ASPMOptComp-
LnkCtl: ASPM Disabled; RCB 128 bytes, Disabled- CommClk+
ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
LnkSta: Speed 2.5GT/s (downgraded), Width x1 (downgraded)
TrErr- Train- SlotClk+ DLActive+ BWMgmt- ABWMgmt-
RootCap: CRSVisible-
RootCtl: ErrCorrectable- ErrNon-Fatal- ErrFatal- PMEIntEna+ CRSVisible-
RootSta: PME ReqID 0000, PMEStatus- PMEPending-
DevCap2: Completion Timeout: Range ABCD, TimeoutDis+ NROPrPrP- LTR-
10BitTagComp- 10BitTagReq- OBFF Not Supported, ExtFmt- EETLPPrefix-
EmergencyPowerReduction Not Supported, EmergencyPowerReductionInit-
FRS- LN System CLS Not Supported, TPHComp- ExtTPHComp- ARIFwd-
AtomicOpsCap: Routing- 32bit- 64bit- 128bitCAS-
DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis- LTR- OBFF Disabled, ARIFwd-
AtomicOpsCtl: ReqEn- EgressBlck-
LnkCap2: Supported Link Speeds: 2.5-5GT/s, Crosslink- Retimer- 2Retimers- DRS-
LnkCtl2: Target Link Speed: 5GT/s, EnterCompliance- SpeedDis-
Transmit Margin: Normal Operating Range, EnterModifiedCompliance- ComplianceSOS-
Compliance De-emphasis: -6dB
LnkSta2: Current De-emphasis Level: -3.5dB, EqualizationComplete- EqualizationPhase1-
EqualizationPhase2- EqualizationPhase3- LinkEqualizationRequest-
Retimer- 2Retimers- CrosslinkRes: unsupported
Capabilities: [100 v1] 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
RootCmd: CERptEn+ NFERptEn+ FERptEn+
RootSta: CERcvd- MultCERcvd- UERcvd- MultUERcvd-
FirstFatal- NonFatalMsg- FatalMsg- IntMsg 0
ErrorSrc: ERR_COR: 0000 ERR_FATAL/NONFATAL: 0000
Kernel driver in use: pcieport

0000:01:00.0 Network controller: Qualcomm Atheros AR958x 802.11abgn Wireless Network Adapter (rev 01)
Subsystem: Device 1c14:0061
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-
Interrupt: pin A routed to IRQ 0
Region 0: Memory at 50100000 (64-bit, non-prefetchable) [size=128K]
Expansion ROM at 50200000 [virtual] [disabled] [size=64K]
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=1/4 Maskable+ 64bit+
Address: 0000000000000000 Data: 0000
Masking: 00000000 Pending: 00000000
Capabilities: [70] Express (v2) Endpoint, MSI 00
DevCap: MaxPayload 128 bytes, PhantFunc 0, Latency L0s <1us, L1 <8us
ExtTag- AttnBtn- AttnInd- PwrInd- RBE+ FLReset- SlotPowerLimit 0.000W
DevCtl: CorrErr- NonFatalErr- FatalErr- UnsupReq-
RlxdOrd+ ExtTag- PhantFunc- AuxPwr- NoSnoop-
MaxPayload 128 bytes, MaxReadReq 256 bytes
DevSta: CorrErr- NonFatalErr- FatalErr- UnsupReq- AuxPwr- TransPend-
LnkCap: Port #0, Speed 2.5GT/s, Width x1, ASPM L0s L1, Exit Latency L0s <2us, L1 <64us
ClockPM- Surprise- LLActRep- BwNot- ASPMOptComp-
LnkCtl: ASPM Disabled; RCB 64 bytes, Disabled- CommClk+
ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
LnkSta: Speed 2.5GT/s (ok), Width x1 (ok)
TrErr- Train- SlotClk+ DLActive- BWMgmt- ABWMgmt-
DevCap2: Completion Timeout: Not Supported, 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: 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-
Retimer- 2Retimers- CrosslinkRes: unsupported
Capabilities: [100 v1] 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: [140 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: [300 v1] Device Serial Number 00-00-00-00-00-00-00-00

0001:00:00.0 PCI bridge: Texas Instruments Device b009 (rev 01) (prog-if 00 [Normal decode])
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 89
Region 0: Memory at <ignored> (32-bit, non-prefetchable)
Bus: primary=00, secondary=01, subordinate=ff, sec-latency=0
I/O behind bridge: [disabled]
Memory behind bridge: [disabled]
Prefetchable memory behind bridge: [disabled]
Secondary status: 66MHz- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- <SERR- <PERR-
BridgeCtl: Parity+ SERR- NoISA- VGA- VGA16- MAbort- >Reset- FastB2B-
PriDiscTmr- SecDiscTmr- DiscTmrStat- DiscTmrSERREn-
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=1/1 Maskable- 64bit+
Address: 0000000021020054 Data: 0000
Capabilities: [70] Express (v2) Root Port (Slot-), MSI 00
DevCap: MaxPayload 256 bytes, PhantFunc 0
ExtTag- RBE+
DevCtl: CorrErr+ NonFatalErr+ FatalErr+ UnsupReq+
RlxdOrd+ ExtTag- PhantFunc- AuxPwr- NoSnoop+
MaxPayload 128 bytes, MaxReadReq 256 bytes
DevSta: CorrErr- NonFatalErr- FatalErr- UnsupReq- AuxPwr- TransPend-
LnkCap: Port #0, Speed 5GT/s, Width x2, ASPM L0s, Exit Latency L0s <2us
ClockPM- Surprise- LLActRep+ BwNot- ASPMOptComp-
LnkCtl: ASPM Disabled; RCB 128 bytes, Disabled- CommClk-
ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
LnkSta: Speed 2.5GT/s (downgraded), Width x1 (downgraded)
TrErr- Train- SlotClk+ DLActive- BWMgmt- ABWMgmt-
RootCap: CRSVisible-
RootCtl: ErrCorrectable- ErrNon-Fatal- ErrFatal- PMEIntEna+ CRSVisible-
RootSta: PME ReqID 0000, PMEStatus- PMEPending-
DevCap2: Completion Timeout: Range ABCD, TimeoutDis+ NROPrPrP- LTR-
10BitTagComp- 10BitTagReq- OBFF Not Supported, ExtFmt- EETLPPrefix-
EmergencyPowerReduction Not Supported, EmergencyPowerReductionInit-
FRS- LN System CLS Not Supported, TPHComp- ExtTPHComp- ARIFwd-
AtomicOpsCap: Routing- 32bit- 64bit- 128bitCAS-
DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis- LTR- OBFF Disabled, ARIFwd-
AtomicOpsCtl: ReqEn- EgressBlck-
LnkCap2: Supported Link Speeds: 2.5-5GT/s, Crosslink- Retimer- 2Retimers- DRS-
LnkCtl2: Target Link Speed: 5GT/s, EnterCompliance- SpeedDis-
Transmit Margin: Normal Operating Range, EnterModifiedCompliance- ComplianceSOS-
Compliance De-emphasis: -6dB
LnkSta2: Current De-emphasis Level: -3.5dB, EqualizationComplete- EqualizationPhase1-
EqualizationPhase2- EqualizationPhase3- LinkEqualizationRequest-
Retimer- 2Retimers- CrosslinkRes: unsupported
Capabilities: [100 v1] 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
RootCmd: CERptEn+ NFERptEn+ FERptEn+
RootSta: CERcvd- MultCERcvd- UERcvd- MultUERcvd-
FirstFatal- NonFatalMsg- FatalMsg- IntMsg 0
ErrorSrc: ERR_COR: 0000 ERR_FATAL/NONFATAL: 0000
Kernel driver in use: pcieport

Vendor says that we need to make sure that CONFIG_PCI_MSI is disabled and we have checked that ath9k uses use_msi=0.
We did however try to load ath9k with use_msi=1 and an IRQ does get assigned and wlan0 device is created, but no interrupts ever arrive.

over 4 years ago

0 Daniel Waleniak over 3 years ago

TI__Expert 5715 points

Team,

Are you able to help with our customer's issue?

Thanks,
Daniel

0 Rajarajan Uthayakumar over 3 years ago in reply to Daniel Waleniak

TI__Expert 4314 points

Hi,

My apologies for the delayed response,

Ioannis Skazikis said:
Vendor says that we need to make sure that CONFIG_PCI_MSI is disabled

Yes, it is correct. But we have to disable CONFIG_PCI_MSI using "make menuconfig".

This link may help: https://software-dl.ti.com/processor-sdk-linux/esd/docs/06_03_00_106/linux/Foundational_Components/Kernel/Kernel_Drivers/PCIe/PCIe_Root_Complex.html?highlight=pcie#pcie-root-complex

Thanks,

Rajarajan U

0 Ioannis Skazikis over 3 years ago in reply to Rajarajan Uthayakumar

Prodigy 60 points

Configuring the kernel with unset CONFIG_PCI_MSI disables the linux kernel support (configuration selection) for the Keystone II pcie host controllers.

Therefore the probe of the linux module which is responsible for the 2 controllers of the CPU 66AK2E05 fails.

PS: From linux kernel `make menuconfig`:

PCI_KEYSTONE_HOST depends on PCI_MSI_IRQ_DOMAIN which depends on PCI_MSI

│ Symbol: PCI_MSI_IRQ_DOMAIN [=n] │
│ Type : bool │
│   Defined at drivers/pci/Kconfig:24 │
│   Depends on: PCI_MSI [=n] │
│   Selects: GENERIC_MSI_IRQ_DOMAIN [=n] │

│ Symbol: PCI_KEYSTONE_HOST [=n] │
│ Type : bool │
│ Prompt: PCI Keystone Host Mode │
│ Location: │
│     -> Bus support │
│       -> PCI controller drivers │
│         -> DesignWare PCI Core Support │
│ (1)       -> TI Keystone PCIe controller (PCI_KEYSTONE [=y]) │
│   Defined at drivers/pci/controller/dwc/Kconfig:116 │
│   Depends on: PCI [=y] && PCI_KEYSTONE [=y] && PCI_MSI_IRQ_DOMAIN [=n] │
│   Selects: PCIE_DW_HOST [=n] │

0 Daniel Waleniak over 3 years ago in reply to Ioannis Skazikis

TI__Expert 5715 points

Dear TI Team,

Do we have any feedback or advice on how to proceed?

Thank you,

Daniel

0 Rajarajan Uthayakumar over 3 years ago in reply to Daniel Waleniak

TI__Expert 4314 points

Hi Daniel,

The issue has been due to the "context" parameter (our case it is "sc" pointer variable) in "request_irq(irq, ath_isr, IRQF_SHARED, "ath9k", sc);" shouldn't be NULL when dealing with a shared interrupt line (IRQF_SHARED flag is on).

To understand, consider the following scenario: you have two identical network cards sharing the same IRQ. The same driver will pass the same interrupt handler function, the same IRQ number, and the same description. There is no way to distinguish the two instances of the registration except via the context parameter.

Therefore, as a precaution, you can't pass a NULL context parameter if you pass the IRQF_SHARED flag. Please try with IRQF_NO_SUSPEND and provide your observation.

We will analyze why this variable is NULL.

In below files : "ti-processor-sdk-linux-k2e-evm-06.03.00.106/board-support/linux-4.19.94+gitAUTOINC+be5389fd85-gbe5389fd85/drivers/net/wireless/ath/ath9k/pci.c"

Line numbers: 975 and 977

if (!msi_enabled)
		ret = request_irq(pdev->irq, ath_isr, IRQF_SHARED, "ath9k", sc);
	else
		ret = request_irq(pdev->irq, ath_isr, 0, "ath9k", sc);

"ti-processor-sdk-linux-k2e-evm-06.03.00.106/board-support/linux-4.19.94+gitAUTOINC+be5389fd85-gbe5389fd85/drivers/net/wireless/ath/ath9k/ahb.c"

Line number: 125

ret = request_irq(irq, ath_isr, IRQF_SHARED, "ath9k", sc);

Thanks,

Rajarajan U

0 Ioannis Skazikis over 3 years ago in reply to Rajarajan Uthayakumar

Prodigy 60 points

Hi Rajarajan,

thank you for the support.

We have applied your suggestion (source code patch) but the result is the same as before The ath9k driver can not be loaded.

The kernel dmesg command (after the code changes) is:

ath9k 0000:01:00.0: enabling device (0140 -> 0142)
ath9k 0000:01:00.0: limiting MRRS to 256
ath9k 0000:01:00.0: request_irq failed
ath9k: probe of 0000:01:00.0 failed with error -22

Any other suggestion that could solve the problem is welcome.

Ioannis.

+1 Athanasios Kokkinis over 3 years ago in reply to Ioannis Skazikis

Prodigy 30 points

Dear all,

We have observed similar issues and the solution was to set the interrupt type of the legacy interrupt-controller.

This can be done by setting the #interrupt-cells = <2> at the legacy-interrupt-controller.
You need to modify the interrupt map as well. Add IRQ_TYPE_EDGE_RISING at the end
of each line of the interrupt-map.

Regards,
Thanasis

0 Ioannis Skazikis over 3 years ago in reply to Athanasios Kokkinis

Prodigy 60 points

Hi Thanasis,

The suggested solution solved our problem.

Well done!

Regards,

Ioannis.

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66AK2E05: Keystone II - WiFi PCIe card (ath9k) - NO MSI SUPPORT - Interrupt