DC CVAC, Data or unified Cache line Clean by VA to PoC

The DC CVAC characteristics are:

Purpose

Clean data cache by address to Point of Coherency.

Configuration

AArch64 System instruction DC CVAC performs the same function as AArch32 System instruction DCCMVAC.

Attributes

DC CVAC is a 64-bit System instruction.

Field descriptions

6362616059585756555453525150494847464544434241403938373635343332
313029282726252423222120191817161514131211109876543210
Virtual address to use
Virtual address to use

Bits [63:0]

Virtual address to use. No alignment restrictions apply to this VA.

Executing the DC CVAC instruction

If EL0 access is enabled, when executed at EL0, this instruction requires read access permission to the VA, otherwise it generates a Permission fault, subject to the constraints described in 'Permission fault'.

Execution of this instruction might require an address translation from VA to PA, and that translation might fault. For more information, see 'The data cache maintenance instruction (DC)'.

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

DC CVAC, <Xt>

op0op1CRnCRmop2
0b010b0110b01110b10100b001

if PSTATE.EL == EL0 then if !(EL2Enabled() && HCR_EL2.<E2H,TGE> == '11') && SCTLR_EL1.UCI == '0' then if EL2Enabled() && HCR_EL2.TGE == '1' then AArch64.SystemAccessTrap(EL2, 0x18); else AArch64.SystemAccessTrap(EL1, 0x18); elsif EL2Enabled() && HCR_EL2.<E2H,TGE> != '11' && HCR_EL2.TPCP == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && HCR_EL2.<E2H,TGE> != '11' && (!HaveEL(EL3) || SCR_EL3.FGTEn == '1') && HFGITR_EL2.DCCVAC == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && HCR_EL2.<E2H,TGE> == '11' && SCTLR_EL2.UCI == '0' then AArch64.SystemAccessTrap(EL2, 0x18); else AArch64.DC(X[t, 64], CacheType_Data, CacheOp_Clean, CacheOpScope_PoC); elsif PSTATE.EL == EL1 then if EL2Enabled() && HCR_EL2.TPCP == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && (!HaveEL(EL3) || SCR_EL3.FGTEn == '1') && HFGITR_EL2.DCCVAC == '1' then AArch64.SystemAccessTrap(EL2, 0x18); else AArch64.DC(X[t, 64], CacheType_Data, CacheOp_Clean, CacheOpScope_PoC); elsif PSTATE.EL == EL2 then AArch64.DC(X[t, 64], CacheType_Data, CacheOp_Clean, CacheOpScope_PoC); elsif PSTATE.EL == EL3 then AArch64.DC(X[t, 64], CacheType_Data, CacheOp_Clean, CacheOpScope_PoC);


05/07/2022 17:08; b0421fa9a8865165f9b91af9b4a566111f866305

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