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ICC_PCR_EL1

Interrupt Controller Physical Interrupt Priority Control Register (EL1)

Controls the Physical priority mask for the Non-secure, Realm, and Secure Interrupt Domains.

Configuration

This register is banked between ICC_PCR_EL1 and ICC_PCR_EL1_NS and ICC_PCR_EL1_RL and ICC_PCR_EL1_S.

This register is present only when FEAT_GCIE is implemented and FEAT_AA64 is implemented. Otherwise, direct accesses to ICC_PCR_EL1 are UNDEFINED.

Direct accesses at EL3 use the register copy selected based on the following:

Attributes

ICC_PCR_EL1 is a 64-bit register.

This register has the following instances:

Field descriptions

6362616059585756555453525150494847464544434241403938373635343332
313029282726252423222120191817161514131211109876543210
RES0
RES0PRIORITY

Bits [63:5]:

Reserved, RES0.

PRIORITY, bits [4:0]:

The priority mask for the Interrupt Domain.

The reset behavior of this field is:

Access Instructions

Accesses to this register use the following encodings in the System register encoding space:

MRS <Xt>, ICC_PCR_EL1

(op0 = 0b11, op1 = 0b001, CRn = 0b1100, CRm = 0b0000, op2 = 0b010)

if !(IsFeatureImplemented(FEAT_GCIE) && IsFeatureImplemented(FEAT_AA64)) then Undefined(); elsif PSTATE.EL == EL0 then Undefined(); elsif PSTATE.EL == EL1 then if EL2Enabled() && HCR_EL2().IMO == '1' && IsFeatureImplemented(FEAT_GCIE_LEGACY) && ICH_VCTLR_EL2().V3 == '1' then Undefined(); elsif EL2Enabled() && ICH_HFGRTR_EL2().ICC_PCR_EL1 == '0' then AArch64_SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && HCR_EL2().IMO == '1' then X{64}(t) = ICV_PCR_EL1(); elsif HaveEL(EL3) then if EffectiveSCR_EL3_NS() == '0' then X{64}(t) = ICC_PCR_EL1_S(); elsif IsFeatureImplemented(FEAT_RME) && EffectiveSCR_EL3_NSE() == '1' && EffectiveSCR_EL3_NS() == '1' then X{64}(t) = ICC_PCR_EL1_RL(); elsif (!IsFeatureImplemented(FEAT_RME) || EffectiveSCR_EL3_NSE() == '0') && EffectiveSCR_EL3_NS() == '1' then X{64}(t) = ICC_PCR_EL1_NS(); else Undefined(); end; else X{64}(t) = ICC_PCR_EL1(); end; elsif PSTATE.EL == EL2 then if HaveEL(EL3) then if EffectiveSCR_EL3_NS() == '0' then X{64}(t) = ICC_PCR_EL1_S(); elsif IsFeatureImplemented(FEAT_RME) && EffectiveSCR_EL3_NSE() == '1' && EffectiveSCR_EL3_NS() == '1' then X{64}(t) = ICC_PCR_EL1_RL(); elsif (!IsFeatureImplemented(FEAT_RME) || EffectiveSCR_EL3_NSE() == '0') && EffectiveSCR_EL3_NS() == '1' then X{64}(t) = ICC_PCR_EL1_NS(); else Undefined(); end; else X{64}(t) = ICC_PCR_EL1(); end; elsif PSTATE.EL == EL3 then if EffectiveSCR_EL3_NS() == '0' then X{64}(t) = ICC_PCR_EL1_S(); elsif IsFeatureImplemented(FEAT_RME) && EffectiveSCR_EL3_NSE() == '1' && EffectiveSCR_EL3_NS() == '1' then X{64}(t) = ICC_PCR_EL1_RL(); elsif (!IsFeatureImplemented(FEAT_RME) || EffectiveSCR_EL3_NSE() == '0') && EffectiveSCR_EL3_NS() == '1' then X{64}(t) = ICC_PCR_EL1_NS(); else Undefined(); end; end;

MSR ICC_PCR_EL1, <Xt>

(op0 = 0b11, op1 = 0b001, CRn = 0b1100, CRm = 0b0000, op2 = 0b010)

if !(IsFeatureImplemented(FEAT_GCIE) && IsFeatureImplemented(FEAT_AA64)) then Undefined(); elsif PSTATE.EL == EL0 then Undefined(); elsif PSTATE.EL == EL1 then if EL2Enabled() && HCR_EL2().IMO == '1' && IsFeatureImplemented(FEAT_GCIE_LEGACY) && ICH_VCTLR_EL2().V3 == '1' then Undefined(); elsif EL2Enabled() && ICH_HFGWTR_EL2().ICC_PCR_EL1 == '0' then AArch64_SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && HCR_EL2().IMO == '1' then ICV_PCR_EL1() = X{64}(t); elsif HaveEL(EL3) then if EffectiveSCR_EL3_NS() == '0' then ICC_PCR_EL1_S() = X{64}(t); elsif IsFeatureImplemented(FEAT_RME) && EffectiveSCR_EL3_NSE() == '1' && EffectiveSCR_EL3_NS() == '1' then ICC_PCR_EL1_RL() = X{64}(t); elsif (!IsFeatureImplemented(FEAT_RME) || EffectiveSCR_EL3_NSE() == '0') && EffectiveSCR_EL3_NS() == '1' then ICC_PCR_EL1_NS() = X{64}(t); else Undefined(); end; else ICC_PCR_EL1() = X{64}(t); end; elsif PSTATE.EL == EL2 then if HaveEL(EL3) then if EffectiveSCR_EL3_NS() == '0' then ICC_PCR_EL1_S() = X{64}(t); elsif IsFeatureImplemented(FEAT_RME) && EffectiveSCR_EL3_NSE() == '1' && EffectiveSCR_EL3_NS() == '1' then ICC_PCR_EL1_RL() = X{64}(t); elsif (!IsFeatureImplemented(FEAT_RME) || EffectiveSCR_EL3_NSE() == '0') && EffectiveSCR_EL3_NS() == '1' then ICC_PCR_EL1_NS() = X{64}(t); else Undefined(); end; else ICC_PCR_EL1() = X{64}(t); end; elsif PSTATE.EL == EL3 then if EffectiveSCR_EL3_NS() == '0' then ICC_PCR_EL1_S() = X{64}(t); elsif IsFeatureImplemented(FEAT_RME) && EffectiveSCR_EL3_NSE() == '1' && EffectiveSCR_EL3_NS() == '1' then ICC_PCR_EL1_RL() = X{64}(t); elsif (!IsFeatureImplemented(FEAT_RME) || EffectiveSCR_EL3_NSE() == '0') && EffectiveSCR_EL3_NS() == '1' then ICC_PCR_EL1_NS() = X{64}(t); else Undefined(); end; end;


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