ICC_HPPIR0, Interrupt Controller Highest Priority Pending Interrupt Register 0
The ICC_HPPIR0 characteristics are:
Purpose
Indicates the highest priority pending Group 0 interrupt on the CPU interface.
Configuration
AArch32 System register ICC_HPPIR0 performs the same function as AArch64 System register ICC_HPPIR0_EL1.
This register is present only when AArch32 is supported at any Exception level. Otherwise, direct accesses to ICC_HPPIR0 are UNKNOWN.
Attributes
ICC_HPPIR0 is a 32-bit register.
Field descriptions
The ICC_HPPIR0 bit assignments are:
Bits [31:24]
Reserved, RES0.
INTID, bits [23:0]
The INTID of the highest priority pending interrupt, if that interrupt is observable at the current Security state and Exception level.
If the highest priority pending interrupt is not observable, this field contains a special INTID to indicate the reason. These special INTIDs can be one of: 1020, 1021, or 1023. For more information, see 'Special INTIDs' in ARM® Generic Interrupt Controller Architecture Specification, GIC architecture version 3.0 and version 4.0 (ARM IHI 0069).
This field has either 16 or 24 bits implemented. The number of implemented bits can be found in ICC_CTLR.IDbits and ICC_MCTLR.IDbits. If only 16 bits are implemented, bits [23:16] of this register are RES0.
Accessing the ICC_HPPIR0
Accesses to this register use the following encodings:
MRC{<c>}{<q>} <coproc>, {#}<opc1>, <Rt>, <CRn>, <CRm>{, {#}<opc2>}
| coproc | opc1 | CRn | CRm | opc2 |
|---|---|---|---|---|
| 0b1111 | 0b000 | 0b1100 | 0b1000 | 0b010 |
if PSTATE.EL == EL0 then
UNDEFINED;
elsif PSTATE.EL == EL1 then
if Halted() && HaveEL(EL3) && EDSCR.SDD == '1' && boolean IMPLEMENTATION_DEFINED "EL3 trap priority when SDD == '1'" && !ELUsingAArch32(EL3) && SCR_EL3.FIQ == '1' then
UNDEFINED;
elsif Halted() && HaveEL(EL3) && EDSCR.SDD == '1' && boolean IMPLEMENTATION_DEFINED "EL3 trap priority when SDD == '1'" && ELUsingAArch32(EL3) && PSTATE.M != M32_Monitor && SCR.FIQ == '1' then
UNDEFINED;
elsif EL2Enabled() && !ELUsingAArch32(EL2) && HSTR_EL2.T12 == '1' then
AArch64.AArch32SystemAccessTrap(EL2, 0x03);
elsif EL2Enabled() && ELUsingAArch32(EL2) && HSTR.T12 == '1' then
AArch32.TakeHypTrapException(0x03);
elsif ICC_SRE.SRE == '0' then
UNDEFINED;
elsif EL2Enabled() && !ELUsingAArch32(EL2) && ICH_HCR_EL2.TALL0 == '1' then
AArch64.AArch32SystemAccessTrap(EL2, 0x03);
elsif EL2Enabled() && ELUsingAArch32(EL2) && ICH_HCR.TALL0 == '1' then
AArch32.TakeHypTrapException(0x03);
elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.FMO == '1' then
return ICV_HPPIR0;
elsif EL2Enabled() && ELUsingAArch32(EL2) && HCR.FMO == '1' then
return ICV_HPPIR0;
elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && SCR_EL3.FIQ == '1' then
if Halted() && EDSCR.SDD == '1' then
UNDEFINED;
else
AArch64.AArch32SystemAccessTrap(EL3, 0x03);
elsif HaveEL(EL3) && ELUsingAArch32(EL3) && PSTATE.M != M32_Monitor && SCR.FIQ == '1' then
if Halted() && EDSCR.SDD == '1' then
UNDEFINED;
else
AArch32.TakeMonitorTrapException();
else
return ICC_HPPIR0;
elsif PSTATE.EL == EL2 then
if Halted() && HaveEL(EL3) && EDSCR.SDD == '1' && boolean IMPLEMENTATION_DEFINED "EL3 trap priority when SDD == '1'" && !ELUsingAArch32(EL3) && SCR_EL3.FIQ == '1' then
UNDEFINED;
elsif Halted() && HaveEL(EL3) && EDSCR.SDD == '1' && boolean IMPLEMENTATION_DEFINED "EL3 trap priority when SDD == '1'" && ELUsingAArch32(EL3) && SCR.FIQ == '1' then
UNDEFINED;
elsif ICC_HSRE.SRE == '0' then
UNDEFINED;
elsif HaveEL(EL3) && !ELUsingAArch32(EL3) && SCR_EL3.FIQ == '1' then
if Halted() && EDSCR.SDD == '1' then
UNDEFINED;
else
AArch64.AArch32SystemAccessTrap(EL3, 0x03);
elsif HaveEL(EL3) && ELUsingAArch32(EL3) && SCR.FIQ == '1' then
if Halted() && EDSCR.SDD == '1' then
UNDEFINED;
else
AArch32.TakeMonitorTrapException();
else
return ICC_HPPIR0;
elsif PSTATE.EL == EL3 then
if ICC_MSRE.SRE == '0' then
UNDEFINED;
else
return ICC_HPPIR0;