The ICH_HCR_EL2 characteristics are:
Controls the environment for VMs.
AArch64 System register ICH_HCR_EL2 bits [31:0] are architecturally mapped to AArch32 System register ICH_HCR[31:0] .
If EL2 is not implemented, this register is RES0 from EL3.
This register has no effect if EL2 is not enabled in the current Security state.
Some or all RW fields of this register have defined reset values. These apply only if the PE resets into an Exception level that is using AArch64. Otherwise, RW fields in this register reset to architecturally UNKNOWN values.
ICH_HCR_EL2 is a 64-bit register.
The ICH_HCR_EL2 bit assignments are:
63 | 62 | 61 | 60 | 59 | 58 | 57 | 56 | 55 | 54 | 53 | 52 | 51 | 50 | 49 | 48 | 47 | 46 | 45 | 44 | 43 | 42 | 41 | 40 | 39 | 38 | 37 | 36 | 35 | 34 | 33 | 32 |
0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
EOIcount | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | TDIR | TSEI | TALL1 | TALL0 | TC | 0 | 0 | VGrp1DIE | VGrp1EIE | VGrp0DIE | VGrp0EIE | NPIE | LRENPIE | UIE | En | ||||
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 |
Reserved, RES0.
This field is incremented whenever a successful write to a virtual EOIR or DIR register would have resulted in a virtual interrupt deactivation. That is either:
This allows software to manage more active interrupts than there are implemented List Registers.
It is CONSTRAINED UNPREDICTABLE whether a virtual write to EOIR that does not clear a bit in the Active Priorities registers (ICH_AP0R<n>_EL2/ICH_AP1R<n>_EL2) increments EOIcount. Permitted behaviors are:
This field resets to 0.
Reserved, RES0.
Trap EL1 writes to ICC_DIR_EL1 and ICV_DIR_EL1.
TDIR | Meaning |
---|---|
0b0 |
EL1 writes of ICC_DIR_EL1 and ICV_DIR_EL1 are not trapped to EL2, unless trapped by other mechanisms. |
0b1 |
EL1 writes of ICV_DIR_EL1 are trapped to EL2. It is IMPLEMENTATION DEFINED whether writes of ICC_DIR_EL1 are trapped. Not trapping ICC_DIR_EL1 writes is DEPRECATED. |
Support for this bit is OPTIONAL, with support indicated by ICH_VTR_EL2.
If the implementation does not support this trap, this bit is RES0.
Arm deprecates not including this trap bit.
This field resets to 0.
Trap all locally generated SEIs. This bit allows the hypervisor to intercept locally generated SEIs that would otherwise be taken at EL1.
TSEI | Meaning |
---|---|
0b0 |
Locally generated SEIs do not cause a trap to EL2. |
0b1 |
Locally generated SEIs trap to EL2. |
If ICH_VTR_EL2.SEIS is 0, this bit is RES0.
This field resets to 0.
Trap all EL1 accesses to ICC_* and ICV_* System registers for Group 1 interrupts to EL2.
TALL1 | Meaning |
---|---|
0b0 |
EL1 accesses to ICC_* and ICV_* registers for Group 1 interrupts proceed as normal. |
0b1 |
EL1 accesses to ICC_* and ICV_* registers for Group 1 interrupts trap to EL2. |
This field resets to 0.
Trap all EL1 accesses to ICC_* and ICV_* System registers for Group 0 interrupts to EL2.
TALL0 | Meaning |
---|---|
0b0 |
EL1 accesses to ICC_* and ICV_* registers for Group 0 interrupts proceed as normal. |
0b1 |
EL1 accesses to ICC_* and ICV_* registers for Group 0 interrupts trap to EL2. |
This field resets to 0.
Trap all EL1 accesses to System registers that are common to Group 0 and Group 1 to EL2.
TC | Meaning |
---|---|
0b0 |
EL1 accesses to common registers proceed as normal. |
0b1 |
EL1 accesses to common registers trap to EL2. |
This affects accesses to ICC_SGI0R_EL1, ICC_SGI1R_EL1, ICC_ASGI1R_EL1, ICC_CTLR_EL1, ICC_DIR_EL1, ICC_PMR_EL1, ICC_RPR_EL1, ICV_CTLR_EL1, ICV_DIR_EL1, ICV_PMR_EL1, and ICV_RPR_EL1.
This field resets to 0.
Reserved, RES0.
VM Group 1 Disabled Interrupt Enable. Enables the signaling of a maintenance interrupt while signaling of Group 1 interrupts from the virtual CPU interface to the connected vPE is disabled:
VGrp1DIE | Meaning |
---|---|
0b0 |
Maintenance interrupt disabled. |
0b1 |
Maintenance interrupt signaled when ICH_VMCR_EL2.VENG1 is 0. |
This field resets to 0.
VM Group 1 Enabled Interrupt Enable. Enables the signaling of a maintenance interrupt while signaling of Group 1 interrupts from the virtual CPU interface to the connected vPE is enabled:
VGrp1EIE | Meaning |
---|---|
0b0 |
Maintenance interrupt disabled. |
0b1 |
Maintenance interrupt signaled when ICH_VMCR_EL2.VENG1 is 1. |
This field resets to 0.
VM Group 0 Disabled Interrupt Enable. Enables the signaling of a maintenance interrupt while signaling of Group 0 interrupts from the virtual CPU interface to the connected vPE is disabled:
VGrp0DIE | Meaning |
---|---|
0b0 |
Maintenance interrupt disabled. |
0b1 |
Maintenance interrupt signaled when ICH_VMCR_EL2.VENG0 is 0. |
This field resets to 0.
VM Group 0 Enabled Interrupt Enable. Enables the signaling of a maintenance interrupt while signaling of Group 0 interrupts from the virtual CPU interface to the connected vPE is enabled:
VGrp0EIE | Meaning |
---|---|
0b0 |
Maintenance interrupt disabled. |
0b1 |
Maintenance interrupt signaled when ICH_VMCR_EL2.VENG0 is 1. |
This field resets to 0.
No Pending Interrupt Enable. Enables the signaling of a maintenance interrupt when there are no List registers with the State field set to 0b01 (pending):
NPIE | Meaning |
---|---|
0b0 |
Maintenance interrupt disabled. |
0b1 |
Maintenance interrupt signaled while the List registers contain no interrupts in the pending state. |
This field resets to 0.
List Register Entry Not Present Interrupt Enable. Enables the signaling of a maintenance interrupt while the virtual CPU interface does not have a corresponding valid List register entry for an EOI request:
LRENPIE | Meaning |
---|---|
0b0 |
Maintenance interrupt disabled. |
0b1 |
Maintenance interrupt is asserted while the EOIcount field is not 0. |
This field resets to 0.
Underflow Interrupt Enable. Enables the signaling of a maintenance interrupt when the List registers are empty, or hold only one valid entry:
UIE | Meaning |
---|---|
0b0 |
Maintenance interrupt disabled. |
0b1 |
Maintenance interrupt is asserted if none, or only one, of the List register entries is marked as a valid interrupt. |
This field resets to 0.
Enable. Global enable bit for the virtual CPU interface:
En | Meaning |
---|---|
0b0 |
Virtual CPU interface operation disabled. |
0b1 |
Virtual CPU interface operation enabled. |
When this field is set to 0:
This field is RES0 when SCR_EL3.{NS,EEL2}=={0,0}
This field resets to 0.
Accesses to this register use the following encodings:
op0 | CRn | op1 | op2 | CRm |
---|---|---|---|---|
0b11 | 0b1100 | 0b100 | 0b000 | 0b1011 |
if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if EL2Enabled() && HCR_EL2.<NV2,NV> == '11' then return NVMem[0x4C0]; elsif EL2Enabled() && HCR_EL2.NV == '1' then AArch64.SystemAccessTrap(EL2, 0x18); else UNDEFINED; elsif PSTATE.EL == EL2 then if ICC_SRE_EL2.SRE == '0' then AArch64.SystemAccessTrap(EL2, 0x18); else return ICH_HCR_EL2; elsif PSTATE.EL == EL3 then if ICC_SRE_EL3.SRE == '0' then AArch64.SystemAccessTrap(EL3, 0x18); else return ICH_HCR_EL2;
op0 | CRn | op1 | op2 | CRm |
---|---|---|---|---|
0b11 | 0b1100 | 0b100 | 0b000 | 0b1011 |
if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if EL2Enabled() && HCR_EL2.<NV2,NV> == '11' then NVMem[0x4C0] = X[t]; elsif EL2Enabled() && HCR_EL2.NV == '1' then AArch64.SystemAccessTrap(EL2, 0x18); else UNDEFINED; elsif PSTATE.EL == EL2 then if ICC_SRE_EL2.SRE == '0' then AArch64.SystemAccessTrap(EL2, 0x18); else ICH_HCR_EL2 = X[t]; elsif PSTATE.EL == EL3 then if ICC_SRE_EL3.SRE == '0' then AArch64.SystemAccessTrap(EL3, 0x18); else ICH_HCR_EL2 = X[t];
13/12/2018 16:42; 6379d01c197f1d40720d32d0f84c419c9187c009
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