Ongoing U320 AIC7902 Seagate ST318453LW issues, SCB timed out

[Don Bowman]

On some systems I am sometimes getting this error pop out.
It seems to track the system for some reason. This is
not a bad cable, signals look good on oscope.

Drive is: SEAGATE ST318453LW, FW 0005
Controller is:
ahd1 at pci3:2:1:  class=0x010000 card=0x005f9005 chip=0x801f9005 rev=0x03
hdr=0x00
    vendor   = 'Adaptec'
    device   = 'AIC-7902 Ultra320 SCSI Host Adapter'
    class    = mass storage
    subclass = SCSI

this drive is the only device (other than the controller) on
the SCSI chain.

The ahd driver is RELENG_4.

The error occurs while doing commands such as 'dd if=/dev/da0 of=/dev/null
bs=20k'
while causing swapping to occur. The error may occur once or twice a day.

I don't know how to move ahead on this problem. I assume that this
indicates that the drive and host controller are out of sync
on a command somehow.

Please advise on how to proceed.

(da0:ahd0:0:0:0): SCB 0x1a - timed out
>>>>>>>>>>>>>>>>>> Dump Card State Begins <<<<<<<<<<<<<<<<<
ahd0: Dumping Card State at program address 0x22 Mode 0x33
Card was paused
HS_MAILBOX[0x0] INTCTL[0xc0]:(SWTMINTEN|SWTMINTMASK)
SEQINTSTAT[0x10]:(SEQ_SWTMRTO) SAVED_MODE[0x11]
DFFSTAT[0x30]:(CURRFIFO_0|FIFO0FREE|FIFO
1FREE)
SCSISIGI[0x0]:(P_DATAOUT) SCSIPHASE[0x0] SCSIBUS[0x0]
LASTPHASE[0x1]:(P_DATAOUT|P_BUSFREE) SCSISEQ0[0x0]
SCSISEQ1[0x12]:(ENAUTOATNP|ENRSELI) SEQCTL0[0x10]:(FASTMODE)
SEQINTCTL[0x0] SEQ_FLAGS[0x0] SEQ_FLAGS2[0x0] SSTAT0[0x0]
SSTAT1[0x8]:(BUSFREE) SSTAT2[0x0] SSTAT3[0x0] PERRDIAG[0x8]:(AIPERR)
SIMODE1[0xa4]:(ENSCSIPERR|ENSCSIRST|ENSELTIMO) LQISTAT0[0x0]
LQISTAT1[0x0] LQISTAT2[0x0] LQOSTAT0[0x0] LQOSTAT1[0x0]
LQOSTAT2[0x1]:(LQOSTOP0)

SCB Count = 64 CMDS_PENDING = 13 LASTSCB 0x3b CURRSCB 0x3b NEXTSCB 0xffc0
qinstart = 57689 qinfifonext = 57689
QINFIFO:
WAITING_TID_QUEUES:
Pending list:
 59 FIFO_USE[0x0] SCB_CONTROL[0x60]:(TAG_ENB|DISCENB) SCB_SCSIID[0x7]
 16 FIFO_USE[0x0] SCB_CONTROL[0x60]:(TAG_ENB|DISCENB) SCB_SCSIID[0x7]
 37 FIFO_USE[0x0] SCB_CONTROL[0x60]:(TAG_ENB|DISCENB) SCB_SCSIID[0x7]
  2 FIFO_USE[0x0] SCB_CONTROL[0x60]:(TAG_ENB|DISCENB) SCB_SCSIID[0x7]
 47 FIFO_USE[0x0] SCB_CONTROL[0x60]:(TAG_ENB|DISCENB) SCB_SCSIID[0x7]
 45 FIFO_USE[0x0] SCB_CONTROL[0x60]:(TAG_ENB|DISCENB) SCB_SCSIID[0x7]
 51 FIFO_USE[0x0] SCB_CONTROL[0x60]:(TAG_ENB|DISCENB) SCB_SCSIID[0x7]
 23 FIFO_USE[0x0] SCB_CONTROL[0x60]:(TAG_ENB|DISCENB) SCB_SCSIID[0x7]
 17 FIFO_USE[0x0] SCB_CONTROL[0x60]:(TAG_ENB|DISCENB) SCB_SCSIID[0x7]
  8 FIFO_USE[0x0] SCB_CONTROL[0x60]:(TAG_ENB|DISCENB) SCB_SCSIID[0x7]
 43 FIFO_USE[0x0] SCB_CONTROL[0x60]:(TAG_ENB|DISCENB) SCB_SCSIID[0x7]
 24 FIFO_USE[0x0] SCB_CONTROL[0x60]:(TAG_ENB|DISCENB) SCB_SCSIID[0x7]
 26 FIFO_USE[0x0] SCB_CONTROL[0x60]:(TAG_ENB|DISCENB) SCB_SCSIID[0x7]
Total 13
Kernel Free SCB list: 42 4 25 32 35 33 27 54 10 34 29 5 62 7 38 31 19 44 6
18 52 56 41 13 46 3 55 39 15 12 21 30 36 58 61 11 22 0 57 40 60 20 53 14 63
28 50 1 9 49 48
Sequencer Complete DMA-inprog list:
Sequencer Complete list:
Sequencer DMA-Up and Complete list:

ahd0: FIFO0 Free, LONGJMP == 0x8257, SCB 0x1a
SEQIMODE[0x3f]:(ENCFG4TCMD|ENCFG4ICMD|ENCFG4TSTAT|ENCFG4ISTAT|ENCFG4DATA|ENS
AVEPTRS)
SEQINTSRC[0x0] DFCNTRL[0x0] DFSTATUS[0x89]:(FIFOEMP|HDONE|PRELOAD_AVAIL)
SG_CACHE_SHADOW[0x2]:(LAST_SEG) SG_STATE[0x0] DFFSXFRCTL[0x0]
SOFFCNT[0x0] MDFFSTAT[0x5]:(FIFOFREE|DLZERO) SHADDR = 0x00, SHCNT = 0x0
HADDR = 0x00, HCNT = 0x0 CCSGCTL[0x10]:(SG_CACHE_AVAIL)
ahd0: FIFO1 Free, LONGJMP == 0x805e, SCB 0x2b
SEQIMODE[0x3f]:(ENCFG4TCMD|ENCFG4ICMD|ENCFG4TSTAT|ENCFG4ISTAT|ENCFG4DATA|ENS
AVEPTRS)
SEQINTSRC[0x0] DFCNTRL[0x0] DFSTATUS[0x89]:(FIFOEMP|HDONE|PRELOAD_AVAIL)
SG_CACHE_SHADOW[0x2]:(LAST_SEG) SG_STATE[0x0] DFFSXFRCTL[0x0]
SOFFCNT[0x0] MDFFSTAT[0x5]:(FIFOFREE|DLZERO) SHADDR = 0x00, SHCNT = 0x0
HADDR = 0x00, HCNT = 0x0 CCSGCTL[0x10]:(SG_CACHE_AVAIL)
LQIN: 0x55 0x0 0x0 0x1a 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x80 0x0 0x0
0x0 0x2 0x0  
ahd0: LQISTATE = 0x0, LQOSTATE = 0x0, OPTIONMODE = 0x42
ahd0: OS_SPACE_CNT = 0x20 MAXCMDCNT = 0x1
  
SIMODE0[0xc]:(ENOVERRUN|ENIOERR)
CCSCBCTL[0x4]:(CCSCBDIR)
ahd0: REG0 == 0x17, SINDEX = 0x133, DINDEX = 0x102
ahd0: SCBPTR == 0x3b, SCB_NEXT == 0xff00, SCB_NEXT2 == 0xff34
CDB 28 0 0 89 97 56
STACK: 0x14 0x125 0x0 0x0 0x257 0x257 0x26a 0x29
<<<<<<<<<<<<<<<<< Dump Card State Ends >>>>>>>>>>>>>>>>>>
Copied 18 bytes of sense data offset 12: 0x70 0x0 0x6 0x0 0x0 0x0 0x0 0xa
0x0 0x0 0x0 0x0 0x29 0x2 0x2 0x0 0x0 0x0
Aug  6 06:46:36  /kernel: <<<<<<<<<<<<<<<< Dump Card State Ends
>>>>>>>>>>>>>>>>>>