Every 16 kB SRAM page chunks, can be configured
independently for secure and privilege attributes
to maxmize SRAM usage for different aspects of the
application code.
As shown in the example in Figure 11-3, one of the 16 kB SRAM page is provisioned such that:
- 4 kB of SRAM can be accessed
by a secure and unprivileged initiator
- 2 kB of SRAM can be accessed
by a secure and privileged initiator
- 1 kB of SRAM can be accessed
by a non-secure and privileged initiator
- 9 kB of SRAM can be accessed
by a non-secure and unprivileged initiator
The SPC allows for chunks within a page and for pages within the entire SRAM
with secure and privilege property, to be non-continguous. Additionally, by default
the SPC is configurable by a secure and privileged initiator, which allows the
secure context to dynamically allocate memory property. This is extremely useful,
when SRAM has to be allocated for a critical application code from the common memory
pool.
Note: Before changing the SRAM chunk memory property,
it is the secure application's responsibility to ensure that all initiators are
properly configured and any data in SRAM is zero initialized.