MPAM2_EL2, MPAM2 Register (EL2)
The MPAM2_EL2 characteristics are:
Purpose
Holds information to generate MPAM labels for memory requests when executing at EL2.
Configuration
AArch64 System register MPAM2_EL2 bit [63] is architecturally mapped to AArch64 System register MPAM3_EL3[63] when HaveEL(EL3).
AArch64 System register MPAM2_EL2 bit [63] is architecturally mapped to AArch64 System register MPAM1_EL1[63] .
This register is present only when MPAM is implemented. Otherwise, direct accesses to MPAM2_EL2 are UNDEFINED.
This register has no effect if EL2 is not enabled in the current Security state.
Some or all RW fields of this register have defined reset values. These apply only if the PE resets into an Exception level that is using AArch64. Otherwise, RW fields in this register reset to architecturally UNKNOWN values.
Attributes
MPAM2_EL2 is a 64-bit register.
Field descriptions
The MPAM2_EL2 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 |
| MPAMEN | RES0 | TRAPMPAM0EL1 | TRAPMPAM1EL1 | PMG_D | PMG_I | ||||||||||||||||||||||||||
| PARTID_D | PARTID_I | ||||||||||||||||||||||||||||||
| 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 |
MPAMEN, bit [63]
MPAM Enable: MPAM is enabled when MPAMEN == 1. When disabled, all PARTIDs and PMGs are output as their default value in the corresponding ID space.
Values of this field are:
| MPAMEN | Meaning |
|---|---|
| 0b0 |
The default PARTID and default PMG are output in MPAM information from all ELx. |
| 0b1 |
MPAM information is output based on the MPAMn_ELx register for ELn according the MPAM configuration. |
If EL3 is not implemented, this field is read/write.
If EL3 is implemented, this field is read-only and reads the current value of the read/write MPAM3_EL3.MPAMEN bit.
This field resets to 0.
Accessing this field has the following behavior:
- When !HaveEL(EL3), access to this field is RW.
- Otherwise, access to this field is RO.
Bits [62:50]
Reserved, RES0.
TRAPMPAM0EL1, bit [49]
TRAPMPAM0EL1: Trap accesses from EL1 to the MPAM0_EL1 register trap to EL2.
| TRAPMPAM0EL1 | Meaning |
|---|---|
| 0b0 |
Accesses to MPAM0_EL1 from EL1 are not trapped. |
| 0b1 |
Accesses to MPAM0_EL1 from EL1 are trapped to EL2. |
When EL3 is not implemented, this field is reset to 1. When EL3 is implemented, this field resets to UNKNOWN.
TRAPMPAM1EL1, bit [48]
TRAPMPAM1EL1: Trap accesses from EL1 to the MPAM1_EL1 register trap to EL2.
| TRAPMPAM1EL1 | Meaning |
|---|---|
| 0b0 |
Accesses to MPAM1_EL1 from EL1 are not trapped. |
| 0b1 |
Accesses to MPAM1_EL1 from EL1 are trapped to EL2. |
When EL3 is not implemented, this field is reset to 1. When EL3 is implemented, this field is resets to UNKNOWN.
PMG_D, bits [47:40]
Performance monitoring group for data accesses.
This field resets to an architecturally UNKNOWN value.
PMG_I, bits [39:32]
Performance monitoring group for instruction accesses.
This field resets to an architecturally UNKNOWN value.
PARTID_D, bits [31:16]
Partition ID for data accesses, including load and store accesses, made from EL2.
This field resets to an architecturally UNKNOWN value.
PARTID_I, bits [15:0]
Partition ID for instruction accesses made from EL2.
This field resets to an architecturally UNKNOWN value.
Accessing the MPAM2_EL2
None of the fields in this register are permitted to be cached in a TLB.
Accesses to this register use the following encodings:
MRS <Xt>, MPAM2_EL2
| op0 | op1 | CRn | CRm | op2 |
|---|---|---|---|---|
| 0b11 | 0b100 | 0b1010 | 0b0101 | 0b000 |
if PSTATE.EL == EL0 then
UNDEFINED;
elsif PSTATE.EL == EL1 then
if EL2Enabled() && HCR_EL2.NV == '1' then
if HaveEL(EL3) && MPAM3_EL3.TRAPLOWER == '1' then
AArch64.SystemAccessTrap(EL3, 0x18);
else
AArch64.SystemAccessTrap(EL2, 0x18);
else
UNDEFINED;
elsif PSTATE.EL == EL2 then
if HaveEL(EL3) && MPAM3_EL3.TRAPLOWER == '1' then
AArch64.SystemAccessTrap(EL3, 0x18);
else
return MPAM2_EL2;
elsif PSTATE.EL == EL3 then
return MPAM2_EL2;
MSR MPAM2_EL2, <Xt>
| op0 | op1 | CRn | CRm | op2 |
|---|---|---|---|---|
| 0b11 | 0b100 | 0b1010 | 0b0101 | 0b000 |
if PSTATE.EL == EL0 then
UNDEFINED;
elsif PSTATE.EL == EL1 then
if EL2Enabled() && HCR_EL2.NV == '1' then
if HaveEL(EL3) && MPAM3_EL3.TRAPLOWER == '1' then
AArch64.SystemAccessTrap(EL3, 0x18);
else
AArch64.SystemAccessTrap(EL2, 0x18);
else
UNDEFINED;
elsif PSTATE.EL == EL2 then
if HaveEL(EL3) && MPAM3_EL3.TRAPLOWER == '1' then
AArch64.SystemAccessTrap(EL3, 0x18);
else
MPAM2_EL2 = X[t];
elsif PSTATE.EL == EL3 then
MPAM2_EL2 = X[t];
MRS <Xt>, MPAM1_EL1
| op0 | op1 | CRn | CRm | op2 |
|---|---|---|---|---|
| 0b11 | 0b000 | 0b1010 | 0b0101 | 0b000 |
if PSTATE.EL == EL0 then
UNDEFINED;
elsif PSTATE.EL == EL1 then
if HaveEL(EL3) && !ELUsingAArch32(EL3) && MPAM3_EL3.TRAPLOWER == '1' then
AArch64.SystemAccessTrap(EL3, 0x18);
elsif EL2Enabled() && !ELUsingAArch32(EL2) && MPAM2_EL2.TRAPMPAM1EL1 == '1' then
AArch64.SystemAccessTrap(EL2, 0x18);
elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.<NV2,NV1,NV> == '111' then
return NVMem[0x900];
else
return MPAM1_EL1;
elsif PSTATE.EL == EL2 then
if HaveEL(EL3) && MPAM3_EL3.TRAPLOWER == '1' then
AArch64.SystemAccessTrap(EL3, 0x18);
elsif HCR_EL2.E2H == '1' then
return MPAM2_EL2;
else
return MPAM1_EL1;
elsif PSTATE.EL == EL3 then
return MPAM1_EL1;
MSR MPAM1_EL1, <Xt>
| op0 | op1 | CRn | CRm | op2 |
|---|---|---|---|---|
| 0b11 | 0b000 | 0b1010 | 0b0101 | 0b000 |
if PSTATE.EL == EL0 then
UNDEFINED;
elsif PSTATE.EL == EL1 then
if HaveEL(EL3) && !ELUsingAArch32(EL3) && MPAM3_EL3.TRAPLOWER == '1' then
AArch64.SystemAccessTrap(EL3, 0x18);
elsif EL2Enabled() && !ELUsingAArch32(EL2) && MPAM2_EL2.TRAPMPAM1EL1 == '1' then
AArch64.SystemAccessTrap(EL2, 0x18);
elsif EL2Enabled() && !ELUsingAArch32(EL2) && HCR_EL2.<NV2,NV1,NV> == '111' then
NVMem[0x900] = X[t];
else
MPAM1_EL1 = X[t];
elsif PSTATE.EL == EL2 then
if HaveEL(EL3) && MPAM3_EL3.TRAPLOWER == '1' then
AArch64.SystemAccessTrap(EL3, 0x18);
elsif HCR_EL2.E2H == '1' then
MPAM2_EL2 = X[t];
else
MPAM1_EL1 = X[t];
elsif PSTATE.EL == EL3 then
MPAM1_EL1 = X[t];