Altera Cyclone V Device Handbook page 571

cv_54006
2013.12.30
The operating modes are programmable through accesses to the control and status registers in the ACP ID
mapper, available via the level 4 peripheral bus connection. At reset time, the ACP ID mapper defaults to
dynamic ID mapping for all output IDs except ID 2, which resets to a fixed mapping for the Debug Access
Port (DAP) input ID.
Related Information
Cortex-A9 MPU Subsystem with L3 Interconnect
ID Intended Usage
Table 6-4
Table 6-4: ID Intended Usage
Output ID
7
6
5
4
3
2
1
0
AXI User Sideband Override
For masters that cannot drive the AXI user sideband signal of incoming transactions, the ACP ID mapper
can control overriding this signal. The ACP ID mapper can also control which 1 GB coherent window into
memory is accessed by masters of the L3 interconnect. Each fixed mapping can be assigned a different user
sideband signal and memory window to allow specific settings for different masters. All dynamic mappings
share a common user sideband signal and memory window setting.
Transaction Capabilities
At any one time, the ACP ID mapper can accept and issue up to 15 transactions per ID mapping. Read and
write ID mappings are managed in separate lists, allowing more unique input IDs to be remapped at any
given time. If a master issues a series of reads and writes with the same input ID, there are no ordering
restrictions.
Because there are only six output IDs available, there can be no more than six read and six write transactions
with unique IDs in progress at any one time. The write acceptance of the ACP slave is five transactions, and
the read acceptance is 13 transactions. Only four coherent read transactions per ID mapping can be
outstanding at one time.
Cortex-A9 Microprocessor Unit Subsystem
Send Feedback
summarizes the expected usage of the 3-bit output IDs, and their settings at reset.
Dynamic
Dynamic
Fixed at 0x001 (DAP)
on page 6-2
Reset State
ID Intended Usage
Intended Use
Dynamic mapping only
Fixed or dynamic, programmed
by software.
Assigned to the input ID of the
DAP at reset. After reset, can be
either fixed or dynamic,
programmed by software.
Not used by the ACP ID Mapper
Altera Corporation
6-25