GR740-UM-DS, Nov 2017, Version 1.7
393
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GR740
Which instructions are traced is defined in the instruction trace buffer control register [31:28], as
defined in the table below:
The instruction trace buffer is enabled after reset when the DSU_EN signal is HIGH and the BREAK
signal is low.
33.5
DSU memory map
The DSU memory map can be seen in table 523 below. In a multiprocessor systems, the register map
is duplicated and address bits 27 - 24 are used to index the processor.
Table 522.
Trace filter operation
Trace filter
Instructions traced
0x0
All instructions
0x1
SPARC Format 2 instructions
0x2
Control-flow changes. All Call, branch and trap instructions including branch targets
0x4
SPARC Format 1 instructions (CALL)
0x8
SPARC Format 3 instructions except LOAD or STORE
0xC
SPARC Format 3 LOAD or STORE instructions
0xD
SPARC Format 3 LOAD or STORE instructions to alternate space
0xE
SPARC Format 3 LOAD or STORE instructions to alternate space 0x80 - 0xFF
Load and stores to ASI 0x80 - 0xFF do not cause operations on the on-chip bus and can be used to
implement software trace points.
Table 523.
DSU memory map
Address offset
Register
0x000000
DSU control register
0x000008
Time tag counter
0x000020
Break and Single Step register
0x000024
Debug Mode Mask register
0x000040
AHB trace buffer control register
0x000044
AHB trace buffer index register
0x000048
AHB trace buffer filter control register
0x00004c
AHB trace buffer filter mask register
0x000050
AHB breakpoint address 1
0x000054
AHB mask register 1
0x000058
AHB breakpoint address 2
0x00005c
AHB mask register 2
0x000070
Instruction count register
0x000080
AHB watchpoint control register
0x000090 - 0x00009C
AHB watchpoint 1 data registers
0x0000A0 - 0x0000AC
AHB watchpoint 1 mask registers
0x0000B0 - 0x0000BC
AHB watchpoint 2 data registers
0x0000C0 - 0x0000CC
AHB watchpoint 2 mask registers
0x100000 - 0x10FFFF
Instruction trace buffer (..0: Trace bits 127 - 96, ..4: Trace bits 95 - 64,
..8: Trace bits 63 - 32, ..C : Trace bits 31 - 0)
0x110000
Instruction Trace buffer control register 0
0x110004
Instruction Trace buffer control register 1
0x200000 - 0x210000
AHB trace buffer (..0: Trace bits 127 - 96, ..4: Trace bits 95 - 64,
..8: Trace bits 63 - 32, ..C : Trace bits 31 - 0)