3.2.14 TZSwitch

Allow TrustZone secure/normal bus signals to be routed separately. This model is written in LISA+.

TZSwitch contains the following CADI targets:

  • PVBusMapper
  • TZSwitch

TZSwitch contains the following MTI components:

TZSwitch - about

The default behavior is to forward secure transactions to pvbus_port_a, and normal transactions to pvbus_port_b.

You must only use TZSwitches if the routing decisions change infrequently, for example as part of a memory remap.

Additional parameter information

The secure and normal parameter values control the initial state of this component:

0
Ignore these transactions.
1
Forward the transactions to pvbus_port_a.
2
Forward the transactions to pvbus_port_b.
3
Generate an abort for these transactions.

The numbers used for initial configuration are not the same as the enumeration constants used to control routing at runtime.

Table 3-60 Ports

Name Protocol Type Description
control TZSwitchControl Slave Controls routing of transactions.
pvbus_input PVBus Slave Slave port for connection to PVBus master/decoder.
pvbus_port_a PVBus Master Output port a.
pvbus_port_b PVBus Master Output port b.

Table 3-61 Parameters for PVBusMapper

Name Type Default value Description
pvbusmodifier.handling_of_dvm_messages_from_downstream string "forward" What to do with DVM (Distributed Virtual Memory) messages received from downstream. The options are to 'forward' them upstream unaltered, to 'terminate' them, or to 'handle' them locally and get called through handleDownstreamDVMMessage()
pvbusmodifier.handling_of_dvm_messages_from_upstream string "forward" What to do with DVM (Distributed Virtual Memory) messages received from upstream. The options are to 'forward' them downstream unaltered, to 'terminate' them, or to 'handle' them locally and get called through handleUpstreamDVMMessage()
pvbusmodifier.handling_of_upstream_snoop_requests string "forward" What to do with snoop requests from downstream. The options are to 'forward', 'terminate' or 'handle'. NOTE that currently the snoop request addresses are _not_ translated and so if your device alters the address translation then you will almost certainly want to 'terminate'.

Table 3-62 Parameters for TZSwitch

Name Type Default value Description
normal int 0x2 Normal Port
secure int 0x1 Secure Port
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