P5000 SMBus i2c 超时

核心问题

　　启动刚启动就会出现：

[root@PlatOS ~]# dmesg | grep 0000:00:0f.0:
[    0.677240] pci 0000:00:0f.0: [8086:18ac] type 00 class 0x088000
[    0.678023] pci 0000:00:0f.0: reg 0x10: [mem 0x20ffeb39000-0x20ffeb393ff 64bit]
[   99.999023] ismt_smbus 0000:00:0f.0: completion wait timed out
[  102.303036] ismt_smbus 0000:00:0f.0: completion wait timed out

一些验证的数据

lspci

[root@PlatOS ~]#  lspci -vvs 00:0f.0
00:0f.0 System peripheral: Intel Corporation Device 18ac (rev 11)
        Subsystem: Intel Corporation Device 7270
        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
        Interrupt: pin A routed to IRQ 44
        NUMA node: 0
        Region 0: Memory at 20ffeb39000 (64-bit, non-prefetchable) [size=1K]
        Capabilities: [40] Express (v2) Root Complex Integrated Endpoint, MSI 00
                DevCap: MaxPayload 256 bytes, PhantFunc 0
                        ExtTag- RBE+ FLReset+
                DevCtl: CorrErr+ NonFatalErr+ FatalErr+ UnsupReq+
                        RlxdOrd- ExtTag- PhantFunc- AuxPwr- NoSnoop- FLReset-
                        MaxPayload 256 bytes, MaxReadReq 128 bytes
                DevSta: CorrErr- NonFatalErr- FatalErr- UnsupReq- AuxPwr- TransPend-
                DevCap2: Completion Timeout: Not Supported, TimeoutDis+, NROPrPrP-, LTR-
                         10BitTagComp-, 10BitTagReq-, OBFF Not Supported, ExtFmt-, EETLPPrefix-
                         EmergencyPowerReduction Not Supported, EmergencyPowerReductionInit-
                         FRS-
                         AtomicOpsCap: 32bit- 64bit- 128bitCAS-
                DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis-, LTR-, OBFF Disabled
                         AtomicOpsCtl: ReqEn-
        Capabilities: [80] 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: [8c] MSI: Enable+ Count=1/1 Maskable+ 64bit+
                Address: 00000000fee00418  Data: 0000
                Masking: 00000000  Pending: 00000000
        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
        Kernel driver in use: ismt_smbus
        Kernel modules: i2c_ismt

i2cdetect

[root@PlatOS ~]# i2cdetect -l
i2c-1   smbus           SMBus I801 adapter at 5000              SMBus adapter
i2c-2   i2c             AST i2c bit bus                         I2C adapter
i2c-0   smbus           SMBus iSMT adapter at 20ffeb39000       SMBus adapter

lsmod

[root@PlatOS ~]# lsmod | grep i2c
i2c_algo_bit           16384  2 igb,ast
i2c_i801               32768  0
i2c_ismt               24576  0
i2c_dev                20480  0

i2cdetect -y -F 0

[root@PlatOS ~]# sudo i2cdetect -y -F 0
Functionalities implemented by /dev/i2c-0:
I2C                              no
SMBus Quick Command              yes
SMBus Send Byte                  yes
SMBus Receive Byte               yes
SMBus Write Byte                 yes
SMBus Read Byte                  yes
SMBus Write Word                 yes
SMBus Read Word                  yes
SMBus Process Call               yes
SMBus Block Write                yes
SMBus Block Read                 yes
SMBus Block Process Call         no
SMBus PEC                        yes
I2C Block Write                  yes
I2C Block Read                   yes
[root@PlatOS ~]#