Hi ARM experts,
We want to use the lockdown_range/lockdown_select registers in TZC-380 to lockdown the region configurations (region_setup_low_<n>/region_setup_high_<n>/region_attributes_<n>), so no new region configuration can be added after lockdown happen.
However, we found that if we set "0x8000000F" to "lockdown_range" which means enable and lock all regions, write operation to the DDR would fail. From the TZC-380 TRM, "b1111" is valid configuration for bit [3:0] of "lockdown_range" register:
So here are my questions:
1. Does the lockdown_range lock the write operation to the memory region (DDR memory) configured in "region_setup_low_<n>/region_setup_high_<n>" or will it lock the "region_setup_low_<n>/region_setup_high_<n>" registers?
2. If the lockdown_range lock the write operation to "region_setup_low_<n>/region_setup_high_<n>" registers, why region 0 can't be locked?
Very appreciated for your help!