3.2 Result Ring
The result ring contains a completed command’s resultant data pointers and execution
status (successful completion or errors occurred). The 820x writes to the result ring and the
host reads from the result ring. The 820x will write to the result ring when a command
completes and then update its result ring write pointer appropriately.
The size of the result ring is always identical to the size of command pointer ring. The result
ring must be aligned to an 8-byte boundary and reside entirely in a physically contiguous
range of memory.
In general in the case of an error, bits [31:17] of a result ring entry summarize the source
of the error, while bits [63:32] provide a more detailed identification of the error. The error
bits remain set until cleared by the host software.
63 62 61 60 59 58 57 56 55 54 53 52 51 50 49 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 32
CMD_IDX[14:0]
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10
9
8
7
6
5
4
3
2
1
0
Field Name
Description
Bits
Default
CM_DCRC
Channel Manager Data CRC error.
63
0
0
1
Channel Manager did not detect data CRC error
Channel Manager detected data CRC error
CM_KCRC
CM_ECC
Channel Manager Key CRC error.
62
0
0
1
Channel Manager did not detect key CRC error
Channel Manager detected key CRC error
Channel Manager ECC/Parity error.
0
Channel Manager did not detect ECC/Parity error
on this channel
61
0
0
1
Channel Manager detected ECC/Parity error on
this channel
Reserved
60:59
Reserved.
820x – Data Sheet, DS-0157-D
Page88
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