Provides a mechanism for an operating system to access the contents of EDECCR that are otherwise invisible to software, so it can save/restore the contents of EDECCR over powerdown on behalf of the external debugger.
AArch64 System register OSECCR_EL1 bits [31:0] are architecturally mapped to AArch32 System register DBGOSECCR[31:0].
AArch64 System register OSECCR_EL1 bits [31:0] are architecturally mapped to External register EDECCR[31:0].
If OSLSR_EL1.OSLK == 0, then OSECCR_EL1 returns an UNKNOWN value on reads and ignores writes.
OSECCR_EL1 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 | |||||||||||||||||||||||||||||||
| EDECCR | |||||||||||||||||||||||||||||||
Reserved, RES0.
Used for save/restore to EDECCR over powerdown.
Reads or writes to this field are indirect accesses to EDECCR.
Accesses to this register use the following encodings in the System register encoding space:
MRS <Xt>, OSECCR_EL1
| op0 | op1 | CRn | CRm | op2 |
|---|---|---|---|---|
| 0b10 | 0b000 | 0b0000 | 0b0110 | 0b010 |
if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if HaveEL(EL3) && EL3SDDUndefPriority() && MDCR_EL3.TDA == '1' then UNDEFINED; elsif EL2Enabled() && IsFeatureImplemented(FEAT_FGT) && (!HaveEL(EL3) || SCR_EL3.FGTEn == '1') && HDFGRTR_EL2.OSECCR_EL1 == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && MDCR_EL2.<TDE,TDA> != '00' then AArch64.SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && MDCR_EL3.TDA == '1' then if EL3SDDUndef() then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); elsif OSLSR_EL1.OSLK == '0' then X[t, 64] = bits(64) UNKNOWN; else X[t, 64] = OSECCR_EL1; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && EL3SDDUndefPriority() && MDCR_EL3.TDA == '1' then UNDEFINED; elsif HaveEL(EL3) && MDCR_EL3.TDA == '1' then if EL3SDDUndef() then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); elsif OSLSR_EL1.OSLK == '0' then X[t, 64] = bits(64) UNKNOWN; else X[t, 64] = OSECCR_EL1; elsif PSTATE.EL == EL3 then if OSLSR_EL1.OSLK == '0' then X[t, 64] = bits(64) UNKNOWN; else X[t, 64] = OSECCR_EL1;
MSR OSECCR_EL1, <Xt>
| op0 | op1 | CRn | CRm | op2 |
|---|---|---|---|---|
| 0b10 | 0b000 | 0b0000 | 0b0110 | 0b010 |
if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if HaveEL(EL3) && EL3SDDUndefPriority() && MDCR_EL3.TDA == '1' then UNDEFINED; elsif EL2Enabled() && IsFeatureImplemented(FEAT_FGT) && (!HaveEL(EL3) || SCR_EL3.FGTEn == '1') && HDFGWTR_EL2.OSECCR_EL1 == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && MDCR_EL2.<TDE,TDA> != '00' then AArch64.SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && MDCR_EL3.TDA == '1' then if EL3SDDUndef() then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); elsif OSLSR_EL1.OSLK == '0' then return; else OSECCR_EL1 = X[t, 64]; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && EL3SDDUndefPriority() && MDCR_EL3.TDA == '1' then UNDEFINED; elsif HaveEL(EL3) && MDCR_EL3.TDA == '1' then if EL3SDDUndef() then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); elsif OSLSR_EL1.OSLK == '0' then return; else OSECCR_EL1 = X[t, 64]; elsif PSTATE.EL == EL3 then if OSLSR_EL1.OSLK == '0' then return; else OSECCR_EL1 = X[t, 64];