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| Home > Programmers Model > Effect of the Security Extensions on the programmers model > Non-secure access to register fields for Secure interrupt priorities | |||
Most register fields associated with a Secure interrupts are RAZ/WI to Non-secure accesses. The following Non-secure register accesses are exceptions to this rule:
If the priority field corresponds to a Non-secure interrupt the access operates as defined by the Non-secure view of interrupt priority, see Software views of interrupt priority.
If the priority field corresponds to a Secure interrupt, the field is RAZ/WI.
If the current priority mask value is in the range 0x00-0x7F:
a read access returns the value 0x00
the GIC ignores a write access to the ICCPMR.
If the current priority mask value is in the range 0x80-0xFF:
A read access returns the Non-secure view of the current value.
A write access to the ICCPMR succeeds, based on
the Non-secure view of the priority mask value written to the register.
This means a Non-secure write cannot set a priority mask value in
the rage 0x00-0x7F.
The pseudocode in The effect of the Security Extensions on accesses to prioritization registers describes accesses to the ICDIPRs, ICCPMR, and ICCRPR when the GIC implements the Security Extensions.
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