The HACR characteristics are:
Controls trapping to Hyp mode of IMPLEMENTATION DEFINED aspects of Non-secure EL1 or EL0 operation.
This register is part of the Virtualization registers functional group.
AArch32 System register HACR is architecturally mapped to AArch64 System register HACR_EL2.
If EL2 is not implemented, this register is RES0 from EL3.
RW fields in this register reset to architecturally UNKNOWN values.
HACR is a 32-bit register.
The HACR bit assignments are:
31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
IMPLEMENTATION DEFINED |
IMPLEMENTATION DEFINED.
This register can be read using MRC with the following syntax:
MRC <syntax>
This register can be written using MCR with the following syntax:
MCR <syntax>
This syntax uses the following encoding in the System instruction encoding space:
<syntax> | opc1 | opc2 | CRn | coproc | CRm |
---|---|---|---|---|---|
p15, 4, <Rt>, c1, c1, 7 | 100 | 111 | 0001 | 1111 | 0001 |
The register is accessible as follows:
Control | Accessibility | |||||
---|---|---|---|---|---|---|
E2H | TGE | NS | EL0 | EL1 | EL2 | EL3 |
x | x | 0 | - | - | n/a | - |
x | 0 | 1 | - | - | RW | RW |
x | 1 | 1 | - | n/a | RW | RW |
This table applies to all instructions that can access this register.
For a description of the prioritization of any generated exceptions, see section G1.11.2 (Exception priority order) in the ARM® Architecture Reference Manual, ARMv8, for ARMv8-A architecture profile for exceptions taken to AArch32 state, and section D1.13.2 (Synchronous exception prioritization) for exceptions taken to AArch64 state. Subject to the prioritization rules, the following traps and enables are applicable when accessing this register.
When EL2 is implemented and is using AArch64 and SCR_EL3.NS==1 && HCR_EL2.E2H==0 :
If HSTR_EL2.T1==1, Non-secure accesses to this register from EL1 are trapped to EL2.
When EL2 is implemented and is using AArch64 and SCR_EL3.NS==1 && HCR_EL2.E2H==1 && HCR_EL2.TGE==0 :
If HSTR_EL2.T1==1, Non-secure accesses to this register from EL1 are trapped to EL2.
When EL2 is implemented and is using AArch32 and SCR_EL3.NS==1 :
If HSTR.T1==1, Non-secure accesses to this register from EL1 are trapped to Hyp mode.
18/04/2017 17:00
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