Samsung S5PC100, User Manual

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S5PC100 USER’S MANUAL (REV1.0) SECURE DOMAIN MANAGER
11.2-3
1.3 MAIN COMPONENTS
The Secure Domain Conversion (SDC) hardware is largely composed of the Secure Domain Manager (SDM) and
the Trust Zone (TZ) hardware.
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Secure Domain Manger: Composed of the main FSM which generates the control signals to proper block,
the bitmap based violation detector which checks the security rule violation, the LFSR which generates the
Non-Cacheable Previliged Access Random Branch (NC-PA) offset, and the SFR bank for SDM.
•
DMZ ROM: Composed of the region that provides the NC-PA random branch instruction and the hardwired
ROM which generates DMZ entrance code and DMZ code. It is accessed like general ROM.
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TZ Hardware: Please refer to TZ documents from ARM Home page. (www.arm.com)
2 SDM FUNCTIONAL DESCRIPTION
SDM is the main block of domain isolation Hardware scheme in S5PC100. It provides the secure access control
function by replacing CPU's AxPROT[1] with own access control signal. Therefore it does not need TZ Software.
Figure 11.2-3 shows system level block diagram of SDM. SDM controls its own ‘secure domain on’ bit by
observing cortexA8’s bus signals.
DMZ is the special ROM area that connects from normal domain to secure domain, and it is the non-secure
memory area. The pre-SW sequences that progresses the pre-processing to protect the secure resource are
stored in DMZ ROM. The start address of block used in switching between non-secure and secure domain is
stored in SFRs protected by special protection logic. Those SFRs are programmed only in the secure booting
sequence. After secure booting is complete, their value cannot be altered until system reset occurs