SPRUIU1C July 2020 – February 2024 DRA821U , DRA821U-Q1
Firewalls play an important role in implementing overall SoC security by providing a means to allow or restrict access to device resources to any given master entity or Secure/Non-Secure/Priv/User world. Firewalls are placed at various data path points throughout the SoC to control access to protected asset (Peripheral, memory and so forth).
Firewalls ensure that assets can be protected and are only accessible by allowed master and in selected operation mode (Secure, Non-Secure, Priv, User, write, read and so forth). In case of firewall violations, the transaction is dropped and the appropriate violation code is registered with associated parameters.
There are three types of firewalls, Peripheral firewalls, Memory firewalls (referred as one group Region Based Firewall in the device-specific TRM) and Channelized firewalls.
Each Firewall module in the SoC has a unique Firewall ID that allows software to decode the source of each violation. The Firewall IDs are allocated based on subsystem as part of platform definition. The full SoC view of Firewall IDs for various Firewall modules are captured in each device spec.