NI-Tower System Control
The system control NI-Tower is the interconnect in the system control block which connects the AXI interfaces of RSE, MSCP, Debug block to the CMN-Cyprus interconnect.
The System Control NI-Tower needs to be able to operate in a multi-chip environment, and therefore the RSE is required to program the following memory regions based on the value in the CHIP_ID register in the RSE Integration Layer register block.
Following are the requester side interfaces present in the system control NI-Tower:
- rse_main_axis: Request from RSE. 
- scp_axis: Request from SCP. 
- mcp_axis: Request from MCP. 
- app_axis: Request from AP. 
- lcp_axis: Request from LCP targeting LCP/SCP 
- rse_scp_axis: RSE/SCP access which is filtered out by NIC400 (specifically for region 0x200000000 - 0x23FFFFFFF) and targeted to LCP address space. 
Following table shows the connections in the System Control Interconnect:
| rse_main_axis | scp_axis | mcp_axis | app_axis | lcp_axis | rse_scp_axis | ||
|---|---|---|---|---|---|---|---|
| rse_scp_axim | Accesses allowed to SCP TCM regions, SCP ATU, SCP RAS and INIT Ctrl registers. | X | |||||
| rse_mcp_axim | Accesses allowed to MCP TCM regions, MCP ATU, MCP RAS and INIT Ctrl registers. | X | |||||
| rsm_axim | Shared RAM between RSE, SCP and MCP. | X | X | X | |||
| rsm_apbm | ECC Error record register block for Shared RAM between RSE, SCP and MCP. | X | X | X | |||
| cmn_apbm | CMN Configuration Space access. | X | X | X | |||
| tcu_apbm | TCU configuration path for RSE before the System Control TBU is enabled. | X | |||||
| lcp_axim | LCP Access | X | |||||
| app_axim | AP Access | X | X | X | |||
| app_scp_axim | SCP Access | X | X | ||||
| app_mcp_axim | MCP Access | X | |||||
| lcp_mcp_axim | SCP Access | X | |||||
The address map for PSAM and APU configuration can found here:
<workspace>/tf-m/platform/ext/target/arm/rse/rdv3/bl2/ni_tower_sysctrl_lib.c