Hi Bjorn, Thanks for your answer. Yes, that would be my next step. I am also hoping the latest kernel doesn't have this issue because that would mean I would be stuck with version 4.9. Also I could discover from which patch this stopped working but that would be very time consuming. If I was to add some debug prints where should I start? Would this be done in setup-irq.c? In other words, is "pci_assign_irq" function responsible for all irq assignments? Regards, Billy. On Wed, Oct 7, 2020 at 5:41 PM Bjorn Helgaas <helgaas@xxxxxxxxxx> wrote: > > [+cc Kishon, linux-omap (maybe this is dra7xx-related?)] > > On Wed, Oct 07, 2020 at 10:56:33AM +0100, Billy Araujo wrote: > > Hi, > > > > I have been testing a TI AM57xx board and a NXP iMX8 board with a GPIB > > PCIe card. > > > > TI board (Phytec): https://www.phytec.com/product/phycore-am57x/ > > NXP board (Variscite): > > https://www.variscite.com/product/system-on-module-som/cortex-a53-krait/var-som-mx8m-mini-nxp-i-mx8m-mini/ > > > > The GPIB PCIe card has a Texas Instruments XIO2000(A)/XIO2200A PCI > > Express-to-PCI Bridge. > > > > Issue: > > I have noticed is that on Linux kernel 4.9, the Linux PCI driver > > assigns correctly an IRQ number: > > > > Linux am5728-phycore-rdk 4.9.41-ga962b18-BSP-Yocto-TISDK-AM57xx-PD18.1.0 > > 02:00.0 Communication controller: National Instruments PCIe-GPIB (rev 02) > > Subsystem: National Instruments PCIe-GPIB > > Control: I/O- Mem- BusMaster- SpecCycle- MemWINV- VGASnoop- > > ParErr+ Stepping- SERR+ FastB2B- DisINTx- > > Status: Cap- 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium > > >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx- > > Interrupt: pin A routed to IRQ 470 > > > > On a newer kernel (this case 4.19), PCI driver doesn't assign an IRQ number. > > > > Linux am57xx-phycore-kit 4.19.79-g35d36cd54d #1 SMP PREEMPT Wed Sep 30 > > 14:04:18 UTC 2020 armv7l GNU/Linux > > 02:00.0 Communication controller: National Instruments PCIe-GPIB (rev 02) > > Subsystem: National Instruments PCIe-GPIB > > Control: I/O- Mem- BusMaster- SpecCycle- MemWINV- VGASnoop- > > ParErr+ Stepping- SERR+ FastB2B- DisINTx- > > Status: Cap- 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium > > >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx- > > Interrupt: pin A routed to IRQ 0 > > > > Same issue happened on the NXP board, so it seems Linux related. I > > have tested kernels 4.14, 4.19 and 5.4.3. > > > > The IRQ is important to get the legacy interrupts working. > > > > Looking at the code there has been some refactoring of how PCI assigns > > IRQ number when there is a chain of bridges. I am not too familiar > > with how the code works but I wonder if this has affected how the PCI > > assignment works. > > > > Looking in setup-irq.c: > > > > /* If this device is not on the primary bus, we need to figure out > > which interrupt pin it will come in on. We know which slot it > > will come in on 'cos that slot is where the bridge is. Each > > time the interrupt line passes through a PCI-PCI bridge we must > > apply the swizzle function. */ > > > > Line 44: if (hbrg->swizzle_irq) > > > > From my understanding, this "if" didn't exist in Linux kernel 4.9. If > > swizzle function isn't assigned in the newer kernels it just stays as > > 0. > > > > This might be completely unrelated as I said I have no understanding > > how this code is supposed to work. > > > > What I ask is if anyone has experienced any issues similar to this in > > these more recent kernel versions. > > Sorry for the issue, and thanks very much for the report. Is it > possible to test a current kernel, e.g., v5.8 or v5.9-rc8? > > My guess is this is related to the PCI controller driver; would that > be pci-dra7xx.c? > > > Debug output with the issue: > > > > root@am57xx-phycore-kit:~# uname -a > > Linux am57xx-phycore-kit 4.19.79-g35d36cd54d #1 SMP PREEMPT Wed Sep 30 > > 14:04:18 UTC 2020 armv7l GNU/Linux > > > > root@am57xx-phycore-kit:~# lspci -vv > > 00:00.0 PCI bridge: Texas Instruments Multicore DSP+ARM KeyStone II > > SOC (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 180 > > Region 0: Memory at 20100000 (64-bit, non-prefetchable) [size=1M] > > Bus: primary=00, secondary=01, subordinate=ff, sec-latency=0 > > I/O behind bridge: None > > Memory behind bridge: 20200000-202fffff [size=1M] > > Prefetchable memory behind bridge: None > > 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: 00000000ae15b000 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 512 bytes > > DevSta: CorrErr- NonFatalErr- FatalErr- UnsupReq- > > AuxPwr- TransPend- > > LnkCap: Port #0, Speed 5GT/s, Width x2, ASPM L0s L1, > > Exit Latency L0s <512ns, L1 <64us > > 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- > > RootCtl: ErrCorrectable- ErrNon-Fatal- ErrFatal- > > PMEIntEna+ CRSVisible- > > RootCap: CRSVisible- > > RootSta: PME ReqID 0000, PMEStatus- PMEPending- > > DevCap2: Completion Timeout: Range ABCD, TimeoutDis+, > > LTR-, OBFF Not Supported ARIFwd- > > AtomicOpsCap: Routing- 32bit- 64bit- 128bitCAS- > > DevCtl2: Completion Timeout: 50us to 50ms, > > TimeoutDis-, LTR-, OBFF Disabled ARIFwd- > > AtomicOpsCtl: ReqEn- EgressBlck- > > 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- > > 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 > > 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 > > > > 01:00.0 PCI bridge: Texas Instruments XIO2000(A)/XIO2200A PCI > > Express-to-PCI Bridge (rev 03) (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- > > Bus: primary=01, secondary=02, subordinate=02, sec-latency=0 > > I/O behind bridge: None > > Memory behind bridge: 20200000-202fffff [size=1M] > > Prefetchable memory behind bridge: None > > Secondary status: 66MHz- FastB2B+ ParErr- DEVSEL=medium > > >TAbort- <TAbort- <MAbort+ <SERR- <PERR- > > BridgeCtl: Parity+ SERR- NoISA- VGA- VGA16- MAbort+ >Reset- FastB2B+ > > PriDiscTmr- SecDiscTmr- DiscTmrStat- DiscTmrSERREn- > > Capabilities: [50] Power Management version 2 > > Flags: PMEClk- DSI- D1+ D2+ AuxCurrent=0mA > > PME(D0-,D1-,D2-,D3hot-,D3cold-) > > Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME- > > Bridge: PM- B3+ > > Capabilities: [60] MSI: Enable- Count=1/16 Maskable- 64bit+ > > Address: 0000000000000000 Data: 0000 > > Capabilities: [80] Subsystem: Device 0000:0000 > > Capabilities: [90] Express (v1) PCI-Express to PCI/PCI-X Bridge, MSI 00 > > DevCap: MaxPayload 512 bytes, PhantFunc 0 > > ExtTag- AttnBtn- AttnInd- PwrInd- RBE- > > SlotPowerLimit 0.000W > > DevCtl: CorrErr- NonFatalErr- FatalErr- UnsupReq- > > RlxdOrd- ExtTag- PhantFunc- AuxPwr- NoSnoop+ BrConfRtry- > > MaxPayload 128 bytes, MaxReadReq 512 bytes > > DevSta: CorrErr- NonFatalErr+ FatalErr- UnsupReq- > > AuxPwr- TransPend- > > LnkCap: Port #0, Speed 2.5GT/s, Width x1, ASPM L0s L1, > > Exit Latency L0s <1us, L1 <16us > > 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- > > 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 > > > > 02:00.0 Communication controller: National Instruments PCIe-GPIB (rev 02) > > Subsystem: National Instruments PCIe-GPIB > > Control: I/O- Mem- BusMaster- SpecCycle- MemWINV- VGASnoop- > > ParErr+ Stepping- SERR+ FastB2B- DisINTx- > > Status: Cap- 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium > > >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx- > > Interrupt: pin A routed to IRQ 0 > > Region 0: Memory at 20204000 (32-bit, non-prefetchable) > > [disabled] [size=2K] > > Region 1: Memory at 20200000 (32-bit, non-prefetchable) > > [disabled] [size=16K]
