AArch32 Secure Debug Enable Register
Allows access to the AArch32 register SDER from AArch64 state only. Its value has no effect on execution in AArch64 state.
AArch64 System register SDER32_EL3 bits [63:0] are architecturally mapped to AArch64 System register SDER32_EL2[63:0] when EL2 is implemented and FEAT_SEL2 is implemented.
AArch64 System register SDER32_EL3 bits [31:0] are architecturally mapped to AArch32 System register SDER[31:0].
This register is present only when EL3 is implemented, FEAT_AA32EL1 is implemented, and FEAT_AA64 is implemented. Otherwise, direct accesses to SDER32_EL3 are UNDEFINED.
SDER32_EL3 is a 64-bit register.
| 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 |
| 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 |
| RES0 | |||||||||||||||||||||||||||||||
| RES0 | SUNIDEN | SUIDEN | |||||||||||||||||||||||||||||
Reserved, RES0.
Secure User Non-Invasive Debug Enable.
| SUNIDEN | Meaning |
|---|---|
| 0b0 |
This bit has no effect on non-invasive debug. |
| 0b1 |
Non-invasive debug is allowed in Secure EL0 using AArch32. |
When Secure EL1 is using AArch32, the forms of non-invasive debug affected by this control are:
When Secure EL1 is using AArch64, this bit has no effect.
The reset behavior of this field is:
Secure User Invasive Debug Enable.
| SUIDEN | Meaning |
|---|---|
| 0b0 |
This bit does not affect the generation of debug exceptions at Secure EL0. |
| 0b1 |
If EL1 is using AArch32, debug exceptions from Secure EL0 are enabled. |
The reset behavior of this field is:
Accesses to this register use the following encodings in the System register encoding space:
MRS <Xt>, SDER32_EL3
(op0 = 0b11, op1 = 0b110, CRn = 0b0001, CRm = 0b0001, op2 = 0b001)
if !(HaveEL(EL3) && IsFeatureImplemented(FEAT_AA32EL1) && IsFeatureImplemented(FEAT_AA64)) then UNDEFINED; elsif !HaveEL(EL3) || !IsFeatureImplemented(FEAT_AA32EL1) then UNDEFINED; elsif PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then UNDEFINED; elsif PSTATE.EL == EL2 then UNDEFINED; elsif PSTATE.EL == EL3 then X[t, 64] = SDER32_EL3;
MSR SDER32_EL3, <Xt>
(op0 = 0b11, op1 = 0b110, CRn = 0b0001, CRm = 0b0001, op2 = 0b001)
if !(HaveEL(EL3) && IsFeatureImplemented(FEAT_AA32EL1) && IsFeatureImplemented(FEAT_AA64)) then UNDEFINED; elsif !HaveEL(EL3) || !IsFeatureImplemented(FEAT_AA32EL1) then UNDEFINED; elsif PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then UNDEFINED; elsif PSTATE.EL == EL2 then UNDEFINED; elsif PSTATE.EL == EL3 then SDER32_EL3 = X[t, 64];
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