Visible to Intel only — GUID: sfo1410068056137
Ixiasoft
Visible to Intel only — GUID: sfo1410068056137
Ixiasoft
7.2.2.2. Secure Transaction Protection
The interconnect provides two levels of transaction protection.
- Security Firewalls:
Security firewalls enforce the Secure World read and write transactions. The term "security firewall" and "firewall" may be used interchangeably within the context of this section.
- Privilege filter
The privilege filter leverages the firewall mechanism and provides additional filtering by allowing control of the privilege level of L4 slave transactions. The privilege filter applies to writes only.
All slaves on the SoC are placed behind a security firewall. A subset of slaves are also placed behind a privilege filter. Transactions to these slaves pass through two firewall structures as shown in the figure below. The transaction packet must pass both a security firewall and the privilege filter to reach the slave. A transaction error causes random data or a slave error depending on where the transaction failed and how the error_response bit in the global register of the noc_fw_ddr_l3_ddr_scr module is programmed.
Each firewall has an associated firewall register which can be programmed by the DAP, FPGA fabric or MPU in secure mode only. A subset of the L4 slaves can additionally be programmed to configure their privilege filter policy.