The FCSEIDR characteristics are:
Identifies whether the Fast Context Switch Extension (FCSE) is implemented.
From Armv8, the FCSE is not implemented, so this register is RAZ/WI. Software can access this register to determine that the implementation does not include the FCSE.
This register is present only when EL1 is capable of using AArch32. Otherwise, direct accesses to FCSEIDR are UNDEFINED.
FCSEIDR is a 32-bit register.
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 |
RAZ/WI |
Reserved, RAZ/WI.
Accesses to this register use the following encodings in the System register encoding space:
coproc | opc1 | CRn | CRm | opc2 |
---|---|---|---|---|
0b1111 | 0b000 | 0b1101 | 0b0000 | 0b000 |
if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if EL2Enabled() && !ELUsingAArch32(EL2) && HSTR_EL2.T13 == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && ELUsingAArch32(EL2) && HSTR.T13 == '1' then AArch32.TakeHypTrapException(0x03); else R[t] = FCSEIDR; elsif PSTATE.EL == EL2 then R[t] = FCSEIDR; elsif PSTATE.EL == EL3 then R[t] = FCSEIDR;
coproc | opc1 | CRn | CRm | opc2 |
---|---|---|---|---|
0b1111 | 0b000 | 0b1101 | 0b0000 | 0b000 |
if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if EL2Enabled() && !ELUsingAArch32(EL2) && HSTR_EL2.T13 == '1' then AArch64.AArch32SystemAccessTrap(EL2, 0x03); elsif EL2Enabled() && ELUsingAArch32(EL2) && HSTR.T13 == '1' then AArch32.TakeHypTrapException(0x03); else FCSEIDR = R[t]; elsif PSTATE.EL == EL2 then FCSEIDR = R[t]; elsif PSTATE.EL == EL3 then FCSEIDR = R[t];
05/07/2022 17:08; b0421fa9a8865165f9b91af9b4a566111f866305
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