The DC ZVA characteristics are:
Zero data cache by address. Zeroes a naturally aligned block of N bytes, where the size of N is identified in DCZID_EL0.
DC ZVA is a 64-bit System instruction.
The DC ZVA input value 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 |
Virtual address to use | |||||||||||||||||||||||||||||||
Virtual address to use | |||||||||||||||||||||||||||||||
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 |
Virtual address to use. There is no alignment restriction on the address within the block of N bytes that is used.
When this instruction is executed, it can generate memory faults or watchpoints which are prioritized in the same way as other memory-related faults or watchpoints. If a synchronous data abort fault or a watchpoint is generated, the CM bit in the ESR_ELx.ISS field is set to 0.
If the memory region being zeroed is any type of Device memory, this instruction can give an Alignment fault which is prioritized in the same way as other Alignment faults that are determined by the memory type.
This instruction applies to Normal memory regardless of cacheability attributes.
This instruction behaves as a set of Stores to each byte within the block being accessed, and so it:
Accesses to this instruction use the following encodings:
op0 | op1 | CRn | CRm | op2 |
---|---|---|---|---|
0b01 | 0b011 | 0b0111 | 0b0100 | 0b001 |
if PSTATE.EL == EL0 then if !ELUsingAArch32(EL1) && !(EL2Enabled() && HCR_EL2.<E2H,TGE> == '11') && SCTLR_EL1.DZE == '0' then if EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.TGE == '1' then AArch64.SystemAccessTrap(EL2, 0x18); else AArch64.SystemAccessTrap(EL1, 0x18); elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.<E2H,TGE> != '11' && HCR_EL2.TDZ == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.<E2H,TGE> == '11' && SCTLR_EL2.DZE == '0' then AArch64.SystemAccessTrap(EL2, 0x18); else DC_ZVA(X[t]); elsif PSTATE.EL == EL1 then if EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.TDZ == '1' then AArch64.SystemAccessTrap(EL2, 0x18); else DC_ZVA(X[t]); elsif PSTATE.EL == EL2 then DC_ZVA(X[t]); elsif PSTATE.EL == EL3 then DC_ZVA(X[t]);
27/03/2019 21:59; e5e4db499bf9867a4b93324c4dbac985d3da9376
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