GR740-UM-DS, Nov 2017, Version 1.7
139
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GR740
12.9.10 Group control registers
Table 139.
0x80 - 0x9C - GRPCTRL - Group control register 0 - 7
12.9.11 Diagnostic cache access register
Table 140.
0xC0 - DIAGCTRL - Diagnostic cache access register
31
4
3
2
1
0
BASE[31:4]
R
P AG
0
0
0
0
rw
r
rw rw
31: 4
Base address (BASE) - Group n’s control register is located at offset 0x80 + n*0x4. This field con-
tains the base address of the data structure for the group. The data structure must start on a 16-byte
address boundary.
3: 2
RESERVED
1
Pass-through (P) - If this bit is set to ‘1’ and the group is active (see bit 0 below) the core will pass-
through all accesses made by master in this group and not use the address specified by BASE to per-
form look-ups in main memory. Note that this also means that the access will pass through untrans-
lated when the core is using IOMMU protection (even if the access is outside the translated range
defined by TMASK in Capability register 2).
If this bit is set to ‘0’, the core will use the contents in its cache, or in main memory, to perform
checks and possibly address translation on incoming accesses.
0
Active Group (AG) - Indicates if the group is active. If this bit is set to ‘0’, all accesses made by mas-
ters assigned to this group will be blocked.
If this bit is set to ‘1’, the core will check the P field of this register and possibly also the in-memory
data structure before allowing or blocking the access.
31 30 29
22 21 20 19 18
0
DA RW
RESERVED
DP TP R
SETADDR
0
0
0
0
0
0
NR
rw* rw*
r
rw* rw* r
rw*
31
Diagnostic Access (DA) - When this bit is set to ‘1’ the core will perform a diagnostic operation to
the cache address specified by the SETADDR field. When the operation has finished this bit will be
reset to ‘0’.
30
Read/Write (RW) - If this bit is ‘1’ and the A field is set to ‘1’ the core will perform a read operation
to the cache. The result will be available in the Diagnostic cache access tag and data register(s). If
this bit is set to ‘0’ and the A field is set to ‘1’, the core will write the contents of the Diagnostic
cache access tag and data registers to the internal cache.
29:22
RESERVED
21
Data Parity error (DP) - This bit is set to ‘1’ if a parity error has been detected in the word read from
the cache’s data RAM. This bit can be set even if no diagnostic cache access has been made and it
can also be set after a cache write operation. This bit is read-only.
20
Tag Parity error (TP) - This bit is set to ‘1’ if a parity error has been detected in the word read from
the cache’s tag RAM. This bit can be set even if no diagnostic cache access has been made and it can
also be set after a cache write operation. This bit is read-only.
19
RESERVED
18:0
Cache Set Address (SETADDR) - Set address to use for diagnostic cache access. When a read oper-
ation has been performed, this field should not be changed until all wanted data has been read from
the Diagnostic cache access data and tag registers. Changing this field invalidates the contents of the
data and tag registers.
* This register can only be accessed if STATUS.DE bit in is set to 1