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GR716-DS-UM, May 2019, Version 1.29
156
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GR716
19.7.9 AHB trace buffer filter control register
Table 149.
0x000048 - ATBFC - AHB trace buffer filter control register
19.7.10 AHB trace buffer filter mask registeri
Table 150.
0x00004C - ATBFM - AHB trace buffer filter mask register
19.7.11 AHB trace buffer breakpoint registers
The DSU contains two breakpoint registers for matching AHB addresses. A breakpoint hit is used to
freeze the trace buffer by automatically clearing the enable bit. Freezing can be delayed by program-
ming the DCNT field in the trace buffer control register to a non-zero value. In this case, the DCNT
value will be decremented for each additional trace until it reaches zero, after which the trace buffer is
frozen. A mask register is associated with each breakpoint, allowing breaking on a block of addresses.
Only address bits with the corresponding mask bit set to ‘1’ are compared during breakpoint detec-
tion. To break on AHB load or store accesses, the LD and/or ST bits should be set.
31
14 13 12 11 10
9
8
7
4
3
2
1
0
RESERVED
WPF
R
BPF
RESERVED
PF AF FR FW
0
0
0
0
0
0
0
0
0
r
rw
r
rw
r
rw rw rw rw
31: 14
RESERVED
13: 12
AHB watchpoint filtering (WPF) - Bit 13 of this field applies to AHB watchpoint 2 and bit 12
applies to AHB watchpoint 1. If the WPF bit for a watchpoint is set to ‘1’ then the watchpoint will
not trigger unless the access also passes through the filter. This functionality can be used to, for
instance, set a AHB watchpoint that only triggers if a specified master performs an access to a spec-
ified slave.
11: 10
RESERVED
9: 8
AHB breakpoint filtering (BPF) - Bit 9 of this field applies to AHB breakpoint 2 and bit 8 applies to
AHB breakpoint 1. If the BPF bit for a breakpoint is set to ‘1’ then the breakpoint will not trigger
unless the access also passes through the filter. This functionality can be used to, for instance, set a
AHB breakpoint that only triggers if a specified master performs an access to a specified slave. Note
that if a AHB breakpoint is coupled with an AHB watchpoint then the setting of the corresponding
bit in this field has no effect.
7: 4
RESERVED
3
Performance counter Filter (PF) - If this bit is set to ‘1’, the cores performance counter (statistical)
outputs will be filtered using the same filter settings as used for the trace buffer. If a filter inhibits a
write to the trace buffer, setting this bit to ‘1’ will cause the same filter setting to inhibit the pulse on
the statistical output.
2
Address Filter (AF) - If this bit is set to ‘1’, only the address range defined by AHB trace buffer
breakpoint 2’s address and mask will be included in the trace buffer.
1
Filter Reads (FR) - If this bit is set to ‘1’, read accesses will not be included in the trace buffer.
0
Filter Writes (FW) - If this bit is set to ‘1’, write accesses will not be included in the trace buffer.
31
16 15
0
SMASK[15:0]
MMASK[15:0]
0
0
rw
rw
31: 16
Slave Mask (SMASK) - If SMASK[n] is set to ‘1’, the trace buffer will not save accesses performed
to slave n.
15: 0
Master Mask (MMASK) - If MMASK[n] is set to ‘1’, the trace buffer will not save accesses per-
formed by master n.
Table 151.
0x000050, 0x000058 - ATBBA - AHB trace buffer break address register
31
2
1
0
BADDR[31:2]
R