|Home > Register descriptions > AArch64 system registers > ATCR_EL12 , Alias to Auxiliary Translation Control Register EL1|
The ATCR_EL12 alias allows access to ATCR_EL1 at EL2 or EL3 when HCR_EL2.E2H is set to 1.
This register is only used when Page Based Hardware Attributes (PBHA) is configured by the core.
To access the ATCR_EL1using the ATCR_EL12 alias:
MRS Xt , S< 3 5 c15 c7 0> ; Read ATCR_EL12/ATCR_EL1 into Xt MSR S < 3 5 c15 c7 0 > , Xt ; Write Xt to ATCR_EL12/ATCR_EL1
This syntax is encoded with the following settings in the instruction encoding:
ATCR_EL12 is accessible as follows:
All traps associated with the ATCR_EL1 register that apply at EL2 or EL3 also apply to the ATCR_EL12 alias.
This alias is only accessible when HCR_EL2.E2H == 1.
When HCR_EL2.E2H == 0, access to this alias is UNDEFINED.