TRBBASER_EL1, Trace Buffer Base Address Register

The TRBBASER_EL1 characteristics are:

Purpose

Defines the base address for the trace buffer.

Configuration

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.

Attributes

TRBBASER_EL1 is a 64-bit register.

Field descriptions

6362616059585756555453525150494847464544434241403938373635343332
313029282726252423222120191817161514131211109876543210
BASE
BASERES0

BASE, bits [63:12]

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:

Bits [11:0]

Reserved, RES0.

Accessing TRBBASER_EL1

The PE might ignore a write to TRBBASER_EL1 if any of the following apply:

Accesses to this register use the following encodings in the System register encoding space:

MRS <Xt>, TRBBASER_EL1

op0op1CRnCRmop2
0b110b0000b10010b10110b010

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 IN {'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>

op0op1CRnCRmop2
0b110b0000b10010b10110b010

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 IN {'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];


26/03/2024 09:49; 67c0ae5282a7629ba0ea0ba7267b43cd4f7939f6

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