TRCSEQSTR, Sequencer State Register
The TRCSEQSTR characteristics are:
Purpose
Use this to set, or read, the Sequencer state.
Configuration
AArch64 System register TRCSEQSTR bits [31:0] are architecturally mapped to External register TRCSEQSTR[31:0] .
This register is present only when FEAT_ETE is implemented and TRCIDR5.NUMSEQSTATE != 0b000. Otherwise, direct accesses to TRCSEQSTR are UNDEFINED.
Attributes
TRCSEQSTR is a 64-bit register.
Field descriptions
The TRCSEQSTR bit assignments are:
| 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 |
| RES0 | |||||||||||||||||||||||||||||||
| RES0 | STATE | ||||||||||||||||||||||||||||||
| 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 |
Bits [63:2]
Reserved, RES0.
STATE, bits [1:0]
Set or returns the state of the Sequencer.
| STATE | Meaning |
|---|---|
| 0b00 |
State 0. |
| 0b01 |
State 1. |
| 0b10 |
State 2. |
| 0b11 |
State 3. |
On a Trace unit reset, this field resets to an architecturally UNKNOWN value.
Accessing the TRCSEQSTR
Must be programmed if TRCRSCTLR<a>.GROUP == 0b0010 and TRCRSCTLR<a>.SEQUENCER != 0b0000.
Writes are CONSTRAINED UNPREDICTABLE if the trace unit is not in the Idle state.
Reads from this register might return an UNKNOWN value if the trace unit is not in either of the Idle or Stable states.
Accesses to this register use the following encodings:
MRS <Xt>, TRCSEQSTR
| op0 | op1 | CRn | CRm | op2 |
|---|---|---|---|---|
| 0b10 | 0b001 | 0b0000 | 0b0111 | 0b100 |
if PSTATE.EL == EL0 then
UNDEFINED;
elsif PSTATE.EL == EL1 then
if Halted() && HaveEL(EL3) && EDSCR.SDD == '1' && boolean IMPLEMENTATION_DEFINED "EL3 trap priority when SDD == '1'" && CPTR_EL3.TTA == '1' then
UNDEFINED;
elsif CPACR_EL1.TTA == '1' then
AArch64.SystemAccessTrap(EL1, 0x18);
elsif EL2Enabled() && CPTR_EL2.TTA == '1' then
AArch64.SystemAccessTrap(EL2, 0x18);
elsif EL2Enabled() && (!HaveEL(EL3) || SCR_EL3.FGTEn == '1') && HDFGRTR_EL2.TRCSEQSTR == '1' then
AArch64.SystemAccessTrap(EL2, 0x18);
elsif HaveEL(EL3) && CPTR_EL3.TTA == '1' then
if Halted() && EDSCR.SDD == '1' then
UNDEFINED;
else
AArch64.SystemAccessTrap(EL3, 0x18);
else
return TRCSEQSTR;
elsif PSTATE.EL == EL2 then
if Halted() && HaveEL(EL3) && EDSCR.SDD == '1' && boolean IMPLEMENTATION_DEFINED "EL3 trap priority when SDD == '1'" && CPTR_EL3.TTA == '1' then
UNDEFINED;
elsif CPTR_EL2.TTA == '1' then
AArch64.SystemAccessTrap(EL2, 0x18);
elsif HaveEL(EL3) && CPTR_EL3.TTA == '1' then
if Halted() && EDSCR.SDD == '1' then
UNDEFINED;
else
AArch64.SystemAccessTrap(EL3, 0x18);
else
return TRCSEQSTR;
elsif PSTATE.EL == EL3 then
if CPTR_EL3.TTA == '1' then
AArch64.SystemAccessTrap(EL3, 0x18);
else
return TRCSEQSTR;
MSR TRCSEQSTR, <Xt>
| op0 | op1 | CRn | CRm | op2 |
|---|---|---|---|---|
| 0b10 | 0b001 | 0b0000 | 0b0111 | 0b100 |
if PSTATE.EL == EL0 then
UNDEFINED;
elsif PSTATE.EL == EL1 then
if Halted() && HaveEL(EL3) && EDSCR.SDD == '1' && boolean IMPLEMENTATION_DEFINED "EL3 trap priority when SDD == '1'" && CPTR_EL3.TTA == '1' then
UNDEFINED;
elsif CPACR_EL1.TTA == '1' then
AArch64.SystemAccessTrap(EL1, 0x18);
elsif EL2Enabled() && CPTR_EL2.TTA == '1' then
AArch64.SystemAccessTrap(EL2, 0x18);
elsif EL2Enabled() && (!HaveEL(EL3) || SCR_EL3.FGTEn == '1') && HDFGWTR_EL2.TRCSEQSTR == '1' then
AArch64.SystemAccessTrap(EL2, 0x18);
elsif HaveEL(EL3) && CPTR_EL3.TTA == '1' then
if Halted() && EDSCR.SDD == '1' then
UNDEFINED;
else
AArch64.SystemAccessTrap(EL3, 0x18);
else
TRCSEQSTR = X[t];
elsif PSTATE.EL == EL2 then
if Halted() && HaveEL(EL3) && EDSCR.SDD == '1' && boolean IMPLEMENTATION_DEFINED "EL3 trap priority when SDD == '1'" && CPTR_EL3.TTA == '1' then
UNDEFINED;
elsif CPTR_EL2.TTA == '1' then
AArch64.SystemAccessTrap(EL2, 0x18);
elsif HaveEL(EL3) && CPTR_EL3.TTA == '1' then
if Halted() && EDSCR.SDD == '1' then
UNDEFINED;
else
AArch64.SystemAccessTrap(EL3, 0x18);
else
TRCSEQSTR = X[t];
elsif PSTATE.EL == EL3 then
if CPTR_EL3.TTA == '1' then
AArch64.SystemAccessTrap(EL3, 0x18);
else
TRCSEQSTR = X[t];