Trace Counter Reload Value Register <n>
This sets or returns the reload count value for Counter <n>.
AArch64 System register TRCCNTRLDVR<n> bits [31:0] are architecturally mapped to External register TRCCNTRLDVR<n>[31:0].
This register is present only when FEAT_ETE is implemented and System register access to the trace unit registers is implemented. Otherwise, direct accesses to TRCCNTRLDVR<n> are UNDEFINED.
TRCCNTRLDVR<n> 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 | VALUE | ||||||||||||||||||||||||||||||
Reserved, RES0.
Contains the reload value for Counter <n>. When a reload event occurs for Counter <n> then the trace unit copies the VALUE<n> field into Counter <n>.
The reset behavior of this field is:
Must be programmed if TRCRSCTLR<a>.GROUP == 0b0010 and TRCRSCTLR<a>.COUNTERS[n] == 1.
If the trace unit is not in the Idle state it is CONSTRAINED UNPREDICTABLE whether writes to this register are ignored.
Accesses to this register use the following encodings in the System register encoding space:
MRS <Xt>, TRCCNTRLDVR<m> ; Where m = 0-3
(op0 = 0b10, op1 = 0b001, CRn = 0b0000, CRm = 0b00:m[1:0], op2 = 0b101)
let m:integer = UInt(CRm[1:0]); if !(IsFeatureImplemented(FEAT_ETE) && IsFeatureImplemented(FEAT_TRC_SR)) then Undefined(); elsif m >= NUM_TRACE_COUNTERS then Undefined(); elsif HaveEL(EL3) && !(EffectivelyAtEL0InHost() || EffectivelyAtEL0NotInHost() || PSTATE.EL == EL3) && EL3SDDUndefPriority() && CPTR_EL3().TTA == '1' then Undefined(); elsif PSTATE.EL == EL0 then Undefined(); elsif PSTATE.EL == EL1 then if CPACR_EL1().TTA == '1' then AArch64_SystemAccessTrap(EL1, 0x18); elsif EL2Enabled() && CPTR_EL2().TTA == '1' then AArch64_SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && IsFeatureImplemented(FEAT_FGT) && (!HaveEL(EL3) || SCR_EL3().FGTEn == '1') && HDFGRTR_EL2().TRC == '1' then AArch64_SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && CPTR_EL3().TTA == '1' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x18); end; elsif IsFeatureImplemented(FEAT_TRBE_EXT) && OSLSR_EL1().OSLK == '0' && HaltingAllowed() && EDSCR2().TTA == '1' then Halt(DebugHalt_SoftwareAccess); else X{64}(t) = TRCCNTRLDVR(m); end; elsif PSTATE.EL == EL2 then if CPTR_EL2().TTA == '1' then AArch64_SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && CPTR_EL3().TTA == '1' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x18); end; elsif IsFeatureImplemented(FEAT_TRBE_EXT) && OSLSR_EL1().OSLK == '0' && HaltingAllowed() && EDSCR2().TTA == '1' then Halt(DebugHalt_SoftwareAccess); else X{64}(t) = TRCCNTRLDVR(m); end; elsif PSTATE.EL == EL3 then if CPTR_EL3().TTA == '1' then AArch64_SystemAccessTrap(EL3, 0x18); elsif IsFeatureImplemented(FEAT_TRBE_EXT) && OSLSR_EL1().OSLK == '0' && HaltingAllowed() && EDSCR2().TTA == '1' then Halt(DebugHalt_SoftwareAccess); else X{64}(t) = TRCCNTRLDVR(m); end; end;
MSR TRCCNTRLDVR<m>, <Xt> ; Where m = 0-3
(op0 = 0b10, op1 = 0b001, CRn = 0b0000, CRm = 0b00:m[1:0], op2 = 0b101)
let m:integer = UInt(CRm[1:0]); if !(IsFeatureImplemented(FEAT_ETE) && IsFeatureImplemented(FEAT_TRC_SR)) then Undefined(); elsif m >= NUM_TRACE_COUNTERS then Undefined(); elsif HaveEL(EL3) && !(EffectivelyAtEL0InHost() || EffectivelyAtEL0NotInHost() || PSTATE.EL == EL3) && EL3SDDUndefPriority() && CPTR_EL3().TTA == '1' then Undefined(); elsif PSTATE.EL == EL0 then Undefined(); elsif PSTATE.EL == EL1 then if CPACR_EL1().TTA == '1' then AArch64_SystemAccessTrap(EL1, 0x18); elsif EL2Enabled() && CPTR_EL2().TTA == '1' then AArch64_SystemAccessTrap(EL2, 0x18); elsif EL2Enabled() && IsFeatureImplemented(FEAT_FGT) && (!HaveEL(EL3) || SCR_EL3().FGTEn == '1') && HDFGWTR_EL2().TRC == '1' then AArch64_SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && CPTR_EL3().TTA == '1' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x18); end; elsif IsFeatureImplemented(FEAT_TRBE_EXT) && OSLSR_EL1().OSLK == '0' && HaltingAllowed() && EDSCR2().TTA == '1' then Halt(DebugHalt_SoftwareAccess); else TRCCNTRLDVR(m) = X{64}(t); end; elsif PSTATE.EL == EL2 then if CPTR_EL2().TTA == '1' then AArch64_SystemAccessTrap(EL2, 0x18); elsif HaveEL(EL3) && CPTR_EL3().TTA == '1' then if EL3SDDUndef() then Undefined(); else AArch64_SystemAccessTrap(EL3, 0x18); end; elsif IsFeatureImplemented(FEAT_TRBE_EXT) && OSLSR_EL1().OSLK == '0' && HaltingAllowed() && EDSCR2().TTA == '1' then Halt(DebugHalt_SoftwareAccess); else TRCCNTRLDVR(m) = X{64}(t); end; elsif PSTATE.EL == EL3 then if CPTR_EL3().TTA == '1' then AArch64_SystemAccessTrap(EL3, 0x18); elsif IsFeatureImplemented(FEAT_TRBE_EXT) && OSLSR_EL1().OSLK == '0' && HaltingAllowed() && EDSCR2().TTA == '1' then Halt(DebugHalt_SoftwareAccess); else TRCCNTRLDVR(m) = X{64}(t); end; end;
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