- Problem Statement/Title:

        Dstop: Slot0 dtransid input parity error

- Symptoms:

        'wfail' output reports something similar to the following:

           01  redxl> dumpf load dsmd.dstop.020509.1733.55
           02  Created Thu May  9 17:33:57 2002
           03  By hpost v. 1.2 Generic 112488-04 Mar 18 2002 14:43:00  executing as pid=6822
           04  On ssc name =  rasputin-sc0.SD_RASCAL.West.Sun.COM
           05  Domain =  0=A    Platform = rasputin
           06  Boards in dump: master SC    CPs/CSBs[1:0]: 3
           07            EXB[17:0]: 12100
           08          Slot0[17:0]: 12100
           09          Slot1[17:0]: 12100
           10  -D option, -d
           11  "DSMD DomainStop Dump"
           12  0 errors occurred while creating this dump.
           13  redxl> wfail
           14  SDI EX08/S0  Master_Stop_Status0[31:0] = D004000F
           15          MStop0[3:0]: All SDI logic is DStopped + Recordstopped.
           16  SDI EX08/S0  Dstop0[31:0] = 00818080
           17          Dstop0[16]: D    DARB texp requests all Dstop (M)
           18          Dstop0[23]: D 1E SDI internal Slot0 port requested Dstop
           19  SDI EX08/S0  Slot0_Error1[31:0] = 08008800  Mask = 31444EBF
           20          S0Err1[27]: D 1E Slot0 dtransid input parity error (M)
           21              slt0_{dtransidp,datareqin,datareqout,dstat[1:0],dtarg} = 10
           22              slt0_dtransid[8:0] = 000
           23  FAIL Slot SB8:  Dstop/Rstop detected by SDI
           24  Primary service FRU is Slot SB8.
           25  Secondary service FRU is EXB EX8.
           26  SDI EX13/S0: All SDI is DStopped and RStopped,         requested by DARB.
           27  SDI EX16/S0: All SDI is DStopped and RStopped,         requested by DARB.
           28  DARB C0: enabled ports (expanders)          [17:0]: 16100
           29  DARB C0: other darb req Dstop+Rstop for exps[17:0]: 00100
           30  DARB C1: enabled ports (expanders)          [17:0]: 16100
           31  DARB C1: other darb req Dstop+Rstop for exps[17:0]: 00100
                 

- Troubleshooting:

        The dump header tells us that this Dstop was generated by dsmd (lines 10,11) 
        while a domain was active. This is also evident by the dumpf file name - 
        dsmd.dstop files are created by dsmd as part of an ASR. Walking the
        error chain:

         - Master SDI on EX8 calls for Dstop as directed by itself (line 18)
         - Master SDI on EX8 detects a DTransID input parity error for 
           Slot 0 (line 20). 
         - SB8 is FAILed from the configuration (line 23)
         - SB8 and EX8 are named as primary and secondary FRUs (lines 24,25)

        The SDC on a L1 board and the SDI exchange DTransID and DTarg information.
        The data exchange is parity protected. Since these pathways cross an
        interconnect, a single FRU cannot be isolated. Suspect components ar
        SB8 and EX8.

- Resolution:

        Replace SB8. If errors persist, replace EX8.

- Summary of part number and patch ID's 

        http://infoserver.central/data/syshbk/Devices/System_Board/SYSBD_SunFire_USIIICu.html
        http://infoserver.central/data/syshbk/Systems/SunFire15K/component.centerplane.html

- References and bug IDs

        SunSolve Article 48122
        SDI ASIC Specification

- Additional background information:

        DTransIDs are used for arbitration, deriving data path steering, and
        data identification (tags). The SDC must request access to use the data
        bus to the SDI. When granted, the SDC supplies the target information
        and generates parity. The SDI receives the information and checks 
        parity. A parity error constitutes a Dstop.

        The arbitration connections between the SDI and SDC on a Slot 0 board
        are as follows:

           slt0_datareqin_l     Unidirectional SDC request to use bidirectional path
           slt0_datareqout_l    High Priority request to SDC to get off the data path
                                 in 2 cycles
           slt0_data_l<1:0>     Bidirectional data status (not part of arbitration)
           slt0_dtarg_l         Bidirectional Read/Write bit (write operation when asserted)
           slt0_dtransid_l<8:0> Bidirectional data tag and arbitration steering information
           slt0_dataidp_l       Unidirectional parity on above signals. Generated only by
                                 the SDC and sent to the SDI for checking

        In the case of a parity error, the wfail provides an indication of the
        faulty signal (line 21), but the overall diagnosis is as above.

- Keywords

15K, 12K, SF15K, SF12K, Sun Fire 15K, Enterprise, Server, Sun Fire 12K,
Slot0 dtransid input parity error, dstop