CSCR_EL3, Capability Secure Configuration Register

The CSCR_EL3 characteristics are:

Purpose

Provides control over privileged access to capabilities

Configuration

This register is present only when Morello is implemented and HaveEL(EL3). Otherwise, direct accesses to CSCR_EL3 are UNDEFINED.

RW fields in this register reset to architecturally UNKNOWN values.

Attributes

CSCR_EL3 is a 64-bit register.

Field descriptions

The CSCR_EL3 bit assignments are:

6362616059585756555453525150494847464544434241403938373635343332
RES0
RES0SETTAG
313029282726252423222120191817161514131211109876543210

Bits [63:1]

Reserved, RES0.

SETTAG, bit [0]

Access to privileged capability creating instructions, SCTAG and STCT.

SETTAGMeaning
0b0

No effect.

0b1

Privileged capability creating instructions clear the tag if executed at EL2 or EL1.

This field resets to an architecturally UNKNOWN value.

Accessing the CSCR_EL3

Accesses to this register use the following encodings:

MRS <Xt>, CSCR_EL3

op0op1CRnCRmop2
0b110b1100b00010b00100b011

if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then UNDEFINED; elsif PSTATE.EL == EL2 then UNDEFINED; elsif PSTATE.EL == EL3 then if IsFeatureImplemented("Morello") && !CapIsSystemAccessEnabled() && !Halted() then AArch64.SystemAccessTrap(EL3, 0x18); elsif CPTR_EL3.EC == '0' then AArch64.SystemAccessTrap(EL3, 0x29); else return CSCR_EL3;

MSR CSCR_EL3, <Xt>

op0op1CRnCRmop2
0b110b1100b00010b00100b011

if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then UNDEFINED; elsif PSTATE.EL == EL2 then UNDEFINED; elsif PSTATE.EL == EL3 then if IsFeatureImplemented("Morello") && !CapIsSystemAccessEnabled() && !Halted() then AArch64.SystemAccessTrap(EL3, 0x18); elsif CPTR_EL3.EC == '0' then AArch64.SystemAccessTrap(EL3, 0x29); else CSCR_EL3 = X[t];




12/01/2022 09:56; 05a4944b4b04e7ab50def8c126b479d22136f35b

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