Defines the base address for the trace buffer.
AArch64 System register TRBBASER_EL1 bits [63:0] are architecturally mapped to External register TRBBASER_EL1[63:0] when FEAT_TRBE_EXT is implemented.
This register is present only when FEAT_TRBE is implemented. Otherwise, direct accesses to TRBBASER_EL1 are UNDEFINED.
TRBBASER_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 |
| BASE | |||||||||||||||||||||||||||||||
| BASE | RES0 | ||||||||||||||||||||||||||||||
Trace Buffer Base pointer address. (TRBBASER_EL1.BASE << 12) is the address of the first byte in the trace buffer. Bits [11:0] of the Base pointer address are always zero. If the smallest implemented translation granule is not 4KB, then TRBBASER_EL1[N-1:12] are RES0, where N is the IMPLEMENTATION DEFINED value Log2(smallest implemented translation granule).
The reset behavior of this field is:
Reserved, RES0.
The PE might ignore a write to TRBBASER_EL1 if any of the following apply:
TRBLIMITR_EL1.E == 0b1, and either FEAT_TRBE_EXT is not implemented or the Trace Buffer Unit is using Self-hosted mode.
TRBLIMITR_EL1.XE == 0b1, FEAT_TRBE_EXT is implemented, and the Trace Buffer Unit is using External mode.
Accesses to this register use the following encodings in the System register encoding space:
MRS <Xt>, TRBBASER_EL1
| op0 | op1 | CRn | CRm | op2 |
|---|---|---|---|---|
| 0b11 | 0b000 | 0b1001 | 0b1011 | 0b010 |
if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if HaveEL(EL3) && EL3SDDUndefPriority() && (MDCR_EL3.NSTB[0] == '0' || MDCR_EL3.NSTB[1] != SCR_EL3.NS || (IsFeatureImplemented(FEAT_RME) && MDCR_EL3.NSTBE != SCR_EL3.NSE)) then UNDEFINED; elsif EL2Enabled() && IsFeatureImplemented(FEAT_FGT) && (!HaveEL(EL3) || SCR_EL3.FGTEn == '1') && HDFGRTR_EL2.TRBBASER_EL1 == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && MDCR_EL2.E2TB == 'x0' then AArch64.SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && (MDCR_EL3.NSTB[0] == '0' || MDCR_EL3.NSTB[1] != SCR_EL3.NS || (IsFeatureImplemented(FEAT_RME) && MDCR_EL3.NSTBE != SCR_EL3.NSE)) then if EL3SDDUndef() then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); elsif IsFeatureImplemented(FEAT_TRBE_EXT) && OSLSR_EL1.OSLK == '0' && HaltingAllowed() && EDSCR2.TTA == '1' then Halt(DebugHalt_SoftwareAccess); else X[t, 64] = TRBBASER_EL1; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && EL3SDDUndefPriority() && (MDCR_EL3.NSTB[0] == '0' || MDCR_EL3.NSTB[1] != SCR_EL3.NS || (IsFeatureImplemented(FEAT_RME) && MDCR_EL3.NSTBE != SCR_EL3.NSE)) then UNDEFINED; elsif HaveEL(EL3) && (MDCR_EL3.NSTB[0] == '0' || MDCR_EL3.NSTB[1] != SCR_EL3.NS || (IsFeatureImplemented(FEAT_RME) && MDCR_EL3.NSTBE != SCR_EL3.NSE)) then if EL3SDDUndef() then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); elsif !ELUsingAArch32(EL1) && IsFeatureImplemented(FEAT_TRBE_EXT) && OSLSR_EL1.OSLK == '0' && HaltingAllowed() && EDSCR2.TTA == '1' then Halt(DebugHalt_SoftwareAccess); else X[t, 64] = TRBBASER_EL1; elsif PSTATE.EL == EL3 then if !ELUsingAArch32(EL1) && IsFeatureImplemented(FEAT_TRBE_EXT) && OSLSR_EL1.OSLK == '0' && HaltingAllowed() && EDSCR2.TTA == '1' then Halt(DebugHalt_SoftwareAccess); else X[t, 64] = TRBBASER_EL1;
MSR TRBBASER_EL1, <Xt>
| op0 | op1 | CRn | CRm | op2 |
|---|---|---|---|---|
| 0b11 | 0b000 | 0b1001 | 0b1011 | 0b010 |
if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if HaveEL(EL3) && EL3SDDUndefPriority() && (MDCR_EL3.NSTB[0] == '0' || MDCR_EL3.NSTB[1] != SCR_EL3.NS || (IsFeatureImplemented(FEAT_RME) && MDCR_EL3.NSTBE != SCR_EL3.NSE)) then UNDEFINED; elsif EL2Enabled() && IsFeatureImplemented(FEAT_FGT) && (!HaveEL(EL3) || SCR_EL3.FGTEn == '1') && HDFGWTR_EL2.TRBBASER_EL1 == '1' then AArch64.SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && MDCR_EL2.E2TB == 'x0' then AArch64.SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && (MDCR_EL3.NSTB[0] == '0' || MDCR_EL3.NSTB[1] != SCR_EL3.NS || (IsFeatureImplemented(FEAT_RME) && MDCR_EL3.NSTBE != SCR_EL3.NSE)) then if EL3SDDUndef() then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); elsif IsFeatureImplemented(FEAT_TRBE_EXT) && OSLSR_EL1.OSLK == '0' && HaltingAllowed() && EDSCR2.TTA == '1' then Halt(DebugHalt_SoftwareAccess); else TRBBASER_EL1 = X[t, 64]; elsif PSTATE.EL == EL2 then if HaveEL(EL3) && EL3SDDUndefPriority() && (MDCR_EL3.NSTB[0] == '0' || MDCR_EL3.NSTB[1] != SCR_EL3.NS || (IsFeatureImplemented(FEAT_RME) && MDCR_EL3.NSTBE != SCR_EL3.NSE)) then UNDEFINED; elsif HaveEL(EL3) && (MDCR_EL3.NSTB[0] == '0' || MDCR_EL3.NSTB[1] != SCR_EL3.NS || (IsFeatureImplemented(FEAT_RME) && MDCR_EL3.NSTBE != SCR_EL3.NSE)) then if EL3SDDUndef() then UNDEFINED; else AArch64.SystemAccessTrap(EL3, 0x18); elsif !ELUsingAArch32(EL1) && IsFeatureImplemented(FEAT_TRBE_EXT) && OSLSR_EL1.OSLK == '0' && HaltingAllowed() && EDSCR2.TTA == '1' then Halt(DebugHalt_SoftwareAccess); else TRBBASER_EL1 = X[t, 64]; elsif PSTATE.EL == EL3 then if !ELUsingAArch32(EL1) && IsFeatureImplemented(FEAT_TRBE_EXT) && OSLSR_EL1.OSLK == '0' && HaltingAllowed() && EDSCR2.TTA == '1' then Halt(DebugHalt_SoftwareAccess); else TRBBASER_EL1 = X[t, 64];