i2c-ismt: IRDPE error

i2c-ismt: IRDPE error

[為溢(阿尼先生)]

Hi everyone,

I’m working on a board that using intel iSMT controller to communicate
with custom I2C slave device.
But sometimes I got IRDPE error while reading data from device.

And I got information that there is a Errata about this error and has
a workaround.
Does anyone know the detail about that Errata ?
And have this workaround already be implemented in the latest i2c-ismt driver ?

Thanks.

Best regards
Kenny Cheng.

=== IRDPE Error message ===
=== Kernel version 3.13.11 ===
[   96.776427] priv->dma_buffer (after completion) - 06 24 00 00  24
01 A1 FF  FF FF FF FF  FF FF FF FF  FF FF FF FF  FF FF FF FF  FF FF FF
FF  FF FF FF FF  FF FF FF FF  FF FF FF FF  FF FF FF FF  FF FF FF FF
FF FF FF FF  FF FF FF FF  FF FF FF FF  FF FF FF FF  FF FF FF FF  FF
[   96.799780] Processing completed descriptor
[   96.804464] Descriptor struct:  ffff8802739ae010
[   96.809631]  tgtaddr_rw=0xFE
[   96.812846]  wr_len_cmd=0x07
[   96.816059]  rd_len=    0x28
[   96.819280]  control=   0x68
[   96.822503]  status=    0x00
[   96.825727]  retry=     0x00
[   96.828949]  rxbytes=   0x00
[   96.832171]  txbytes=   0x00
[   96.835393]  dptr_low=  0x73FCFB78
[   96.839198]  dptr_high= 0x00000002
[   96.842995] Dump of the iSMT General Registers
[   96.847969]   GCTRL.... : (0xffffc90000c74000)=0x00000000
[   96.854011]   SMTICL... : (0xffffc90000c74008)=0x0000000000000000
[   96.860830]   ERRINTMSK : (0xffffc90000c74010)=0x00000000
[   96.866871]   ERRAERMSK : (0xffffc90000c74014)=0x00000000
[   96.872905]   ERRSTS... : (0xffffc90000c74018)=0x00000200 <- IRDPE Error
[   96.878948]   ERRINFO.. : (0xffffc90000c7401c)=0x00000029
[   96.884988] Dump of the iSMT Master Registers
[   96.889864]   MDBA..... : (0xffffc90000c74100)=0x00000002739AE000
[   96.896685]   MCTRL.... : (0xffffc90000c74108)=0x00020010
[   96.902728]   MSTS..... : (0xffffc90000c7410c)=0x00020000
[   96.908772]   MDS...... : (0xffffc90000c74110)=0x0000001F
[   96.914814]   RPOLICY.. : (0xffffc90000c74114)=0x00061020
[   96.920856]   TBBA..... : (0xffffc90000c74200)=0x0000000000000000
[   96.927668]   TCTRL.... : (0xffffc90000c74208)=0x00000010
[   96.933710]   TSTS..... : (0xffffc90000c7420c)=0x00000000
[   96.939752]   TBS...... : (0xffffc90000c74210)=0x00000000
[   96.945795]   HTHP..... : (0xffffc90000c74218)=0x00000000
[   96.951838]   FTTP..... : (0xffffc90000c7421c)=0x00000000
[   96.957880]   TRxCTRL.. : (0xffffc90000c74220)=0x00000058
[   96.963921]   TRxSTS... : (0xffffc90000c74224)=0x00000000
[   96.969955]   TACTRL... : (0xffffc90000c74228)=0x00000000
[   96.975998]   TPOLICY.. : (0xffffc90000c7422c)=0x0000001A
[   96.982041]   GPBRCTRL. : (0xffffc90000c74240)=0x00000089
[   96.988084]   GPBRDBUF. : (0xffffc90000c74244)=0x00000000
[   96.994126]   SMTARPCTRL: (0xffffc90000c74280)=0x00000000
[   97.000168]   UDID0.... : (0xffffc90000c74290)=0x8086000000000000
[   97.006989]   UUDID0... : (0xffffc90000c74298)=0x8108808600000024
[   97.013808]   UDID1.... : (0xffffc90000c742a0)=0x8086000000000001
[   97.020617]   UUDID1... : (0xffffc90000c742a8)=0x8108808600000024
[   97.027436]   SPGT..... : (0xffffc90000c74300)=0x40000005
[   97.033478]   SPMT..... : (0xffffc90000c74304)=0x08080000
[   97.039521]   SPST..... : (0xffffc90000c74308)=0x00000000
[   97.045563]   SMBFT.... : (0xffffc90000c7430c)=0x00002024
[   97.051604]   CLTC..... : (0xffffc90000c74310)=0x00000962

Re: i2c-ismt: IRDPE error

[Eudean Sun]

為溢(阿尼先生 <kchengwy <at> gmail.com> writes:

> 
> Hi everyone,
> 
> I’m working on a board that using intel iSMT controller to communicate
> with custom I2C slave device.
> But sometimes I got IRDPE error while reading data from device.
> 
> And I got information that there is a Errata about this error and has
> a workaround.
> Does anyone know the detail about that Errata ?

There is such an errata, details are in the Specification Update for the 
Intel C2000 (Intel Document Number 520653). That is covered under NDA 
though so you'll have to request your own copy.

> And have this workaround already be implemented in the latest i2c-ismt 
driver ?

This change addresses the issue and went into kernel version 3.12:

https://github.com/torvalds/linux/commit/bf4169100c909667ede6af67668b3ecce
6928343