Greetings. We're using a board derived from the MPC8315E. Fairly regularly, the SATA connection will freeze up while we are writing to flash memory:
[ 839.806884] ata2.00: exception Emask 0x10 SAct 0x0 SErr 0x0 action 0x6 frozen [ 839.814201] ata2.00: failed command: WRITE DMA [ 839.818814] ata2.00: cmd ca/00:08:58:95:21/00:00:00:00:00/e1 tag 0 dma 4096 out [ 839.818838] res 50/00:00:98:00:18/00:00:00:00:00/e1 Emask 0x10 (ATA bus error) [ 839.834222] ata2.00: status: { DRDY } [ 839.838046] ata2: hard resetting link [ 839.867942] ata2: setting speed (in hard reset) [ 849.959859] ata2: No Signature Update [ 850.131872] ata2: SATA link up 1.5 Gbps (SStatus 113 SControl 310) [ 850.138219] ata2.00: link online but device misclassified [ 855.143882] ata2.00: qc timeout (cmd 0xec) [ 855.148144] ata2.00: failed to IDENTIFY (I/O error, err_mask=0x4) [ 855.154375] ata2.00: revalidation failed (errno=-5) [ 855.159376] ata2: hard resetting link [ 855.659847] ata2: Hardreset failed, not off-lined 0 [ 855.671839] ata2: setting speed (in hard reset) [ 865.259851] ata2: No Signature Update ... The previous times I saw this, it would eventually recover, and our device would keep on working correctly. However, now that we're doing many more operations per second, it seems that it doesn't have time to recover, and we get a permanent error: [ 925.883824] ata2: No Signature Update [ 926.055893] ata2: SATA link up 1.5 Gbps (SStatus 113 SControl 310) [ 926.062236] ata2.00: link online but device misclassified [ 926.067846] ata2: EH complete [ 926.071337] sd 1:0:0:0: [sda] Unhandled error code [ 926.076283] sd 1:0:0:0: [sda] Result: hostbyte=0x04 driverbyte=0x00 [ 926.082758] sd 1:0:0:0: [sda] CDB: cdb[0]=0x2a: 2a 00 01 21 95 58 00 00 08 00 [ 926.090150] end_request: I/O error, dev sda, sector 18978136 [ 926.096132] sd 1:0:0:0: [sda] Unhandled error code [ 926.101037] sd 1:0:0:0: [sda] Result: hostbyte=0x04 driverbyte=0x00 [ 926.107504] sd 1:0:0:0: [sda] CDB: cdb[0]=0x2a: 2a 00 01 22 2a 00 00 00 10 00 [ 926.114894] end_request: I/O error, dev sda, sector 19016192 [ 926.120811] sd 1:0:0:0: [sda] Unhandled error code [ 926.125719] sd 1:0:0:0: [sda] Result: hostbyte=0x04 driverbyte=0x00 [ 926.132225] sd 1:0:0:0: [sda] CDB: cdb[0]=0x2a: 2a 00 00 00 00 08 00 00 08 00 [ 926.139545] end_request: I/O error, dev sda, sector 8 [ 926.144690] Buffer I/O error on device sda1, logical block 0 [ 926.150437] lost page write due to I/O error on sda1 [ 926.155674] sd 1:0:0:0: [sda] Unhandled error code [ 926.160614] sd 1:0:0:0: [sda] Result: hostbyte=0x04 driverbyte=0x00 [ 926.167073] sd 1:0:0:0: [sda] CDB: cdb[0]=0x2a: 2a 00 01 18 00 18 00 00 08 00 [ 926.174451] end_request: I/O error, dev sda, sector 18350104 And eventually I get nothing but: [ 1177.852326] EXT2-fs (sda1): error: read_inode_bitmap: Cannot read inode bitmap - block_group = 70, inode_bitmap = 2293761 [ 1177.871983] EXT2-fs (sda1): previous I/O error to superblock detected [ 1177.872016] [ 1177.880192] EXT2-fs (sda1): error: read_inode_bitmap: Cannot read inode bitmap - block_group = 70, inode_bitmap = 2293761 [ 1177.893731] EXT2-fs (sda1): previous I/O error to superblock detected [ 1177.893764] At this point, /dev/sda is pretty much unusable, and I have to do at least a reboot to recover. (I don't recall if I had to do a power cycle at this point, though.) I suspect that it is related to errata eLBC-A001 (from MPC8315E Chip Errata, Rev. 3, 09/2011): eLBC-A001: Simultaneous FCM and GPCM or UPM operation may erroneously trigger bus monitor timeout Description: Devices: MPC8315E, MPC8314E When the FCM is in the middle of a long transaction, such as NAND erase or write, another transaction on the GPCM or UPM triggers the bus monitor to start immediately for the GPCM or UPM, even though the GPCM or UPM is still waiting for the FCM to finish and has not yet started its transaction. If the bus monitor timeout value is not programmed for a sufficiently large value, the local bus monitor may time out. This timeout corrupts the current NAND Flash operation and terminate the GPCM or UPM operation. Impact: Local bus monitor may time out unexpectedly and corrupt the NAND transaction. Workaround: Set the local bus monitor timeout value to the maximum by setting LBCR[BMT] = 0 and LBCR[BMTPS] = 0xF. Fix plan: No plans to fix But it seems that erratum is already fixed: http://patchwork.ozlabs.org/patch/96339/ (git patch d08e44570e) Am I reading that correctly? (I'm already writing only one flash sector at a time, but it might be that even a single 0x10000-byte sector takes long enough to trigger the issue.) I also verified that I have the relevant property in my device tree: localbus@e0005000 { ... compatible = "fsl,mpc8315-elbc", "fsl,elbc", "simple-bus"; So, my questions are: 1. Is anyone else seeing something like this? 2. Is there an obvious way for our code to detect that we're in the middle of error recovery, so we can not write to the disk until recovery is complete? 3. Is there any chance that the 1.5Gbps limiting code might have exacerbated the problems? 4. Should I open a support request with Freescale, or if someone from Freescale is already reading this, could you look to see if anyone else has reported it? Kernel is 3.4.36, cpuinfo says: / # cat /proc/cpuinfo processor : 0 cpu : e300c3 clock : 266.666664MHz revision : 2.0 (pvr 8085 0020) bogomips : 66.66 timebase : 33333333 platform : MPC831x RDB Memory : 256 MB device on that SATA link is an InnoDisk SSD: / # dmesg | grep 'ata2' [ 7.729684] ata2: SATA max UDMA/133 irq 45 [ 7.973996] ata2: setting speed (in hard reset) [ 7.984849] ata2: Signature Update detected @ 0 msecs [ 8.390553] ata2: SATA link up 1.5 Gbps (SStatus 113 SControl 310) [ 8.471244] ata2.00: ATA-8: InnoDisk Corp. - mSATA D150Q, 110520B, max UDMA/133 [ 8.478690] ata2.00: 31277232 sectors, multi 16: LBA48 [ 8.484562] ata2.00: configured for UDMA/133 As always, any further hints would be very welcome. Best regards, Anthony Foiani _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev