CONFIDENTIAL
PRELIMINARY
CYNSE10512
CYNSE10256
CYNSE10128
Document #: 38-02069 Rev. *F
Page 36 of 153
5.4.13
Search Result Register (SRR[15:0])
The SRR register is only active when the device is in the Enhanced mode. It contains status information about where the next-
free entry is and what kind of entry it is. There are sixteen SRRs; one SRR associated with one CMPR. The SSR is updated on
a Search operation regardless of hit or miss. Two SRRs are used in one Search operation when MSE is set. The second SRR
is automatically selected to be the register one index higher. Table 5-14 below details the SRR fields.
Table 5-15 below shows the different parts of the INDEX field of the SRR.
Table 5-14. Search Result Register
Field
Index
(decimal)
Initial Value
(binary)
Description
INDEX
[N:0]
0
Index. This field contains the Hit or Miss index inside the Core. N = 17 for
CYNSE10512, 16 for CYNSE10256, 15 for CYNSE10128.
[23:M]
Reserved. M = 18 for CYNSE10512, 17 for CYNSE10256, 16 for CYNSE10128.
Mini-Key
[31:24]
0
Mini-Key. This field contains a copy of the Mini-Key value selected for the Search
operation. The value comes from the selected CPR.
PRIORITY
[39:32]
0
Soft Priority. This field holds the priority value of the sub-block where a successful
search occurs. Otherwise it holds the priority of the next-free entry sub-block. If there
are no free entries, this field is set to the selected CPR’s Soft Priority value. This
field is not valid when STATUS value is Taken.
STATUS
[43:40]
0
Next-free Entry Status. This field contains the status information for the next-free
entry.
The STATUS value is encoded as described below:
0000: Single match. Search hit and there is a single match.
0010: Single free entry. Search miss and there is a single free entry.
0100: Single free sub-block. Search miss and there is a single free sub-block.
0110: Single free block. Search miss and there is a single free block.
0001: Multiple matches. Search hit and there are multiple matches.
0011: Multiple free entries. Search miss and there are multiple free entries
0101: Multiple free sub-blocks. Search miss and there are multiple free sub-blocks.
0111: Multiple free blocks. Search miss and there are multiple free blocks.
1000: Taken. Search miss and there are no free entries.
[62:44]
Reserved.
FLG
[63]
0
Flag. When set to 1, this flag indicates that a Search operation resulted in a miss,
this device has a free entry and the upstream devices in a cascade have a Search
miss with no free entries reported. Note that a device with no free entries can still
have free blocks or sub-blocks.
[71:64]
Reserved.
Table 5-15. SRR’s INDEX Composition Based on STATUS
STATUS
INDEX[17:11]
INDEX[10:9]
INDEX[8:0]
Hit
Block ID
Sub-block ID
Hit Entry Index
Free Entry
Block ID
Sub-block ID
Free Entry Index
Free Sub-block
Block ID
Sub-block ID
All zeros
Free Block
Block ID
All zeros
All zeros
Taken
Undefined
Undefined
Undefined
7
15
23
0
39
47
55
31
63
71
Mini-Key
PRIORITY
INDEX
Figure 5-21. Search Result Register
N = 15 for CYNSE10128
N = 16 for CYNSE10256
N = 17 for CYNSE10512
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