CNTPS_CVAL

Holds the compare value for the secure physical timer, usually accessible at EL3 but configurably accessible at EL1 in Secure state.

Configuration

This register is present only when EL3 is implemented. Otherwise, direct accesses to CNTPS_CVAL_EL1 are UNDEFINED.

Attributes

Field descriptions

CompareValue, bits [63:0]

Holds the secure physical timer CompareValue.

When CNTPS_CTL_EL1.ENABLE is 1, the timer condition is met when (CNTPCT_EL0 - CompareValue) is greater than or equal to zero. This means that CompareValue acts like a 64-bit upcounter timer. When the timer condition is met:

CNTPS_CTL_EL1.ISTATUS is set to 1.
If CNTPS_CTL_EL1.IMASK is 0, an interrupt is generated.

When CNTPS_CTL_EL1.ENABLE is 0, the timer condition is not met, but CNTPCT_EL0 continues to count.

If the Generic counter is implemented at a size less than 64 bits, then this field is permitted to be implemented at the same width as the counter, and the upper bits are RES0.

The value of this field is treated as zero-extended in all counter calculations.

The reset behavior of this field is:

On a Warm reset, this field resets to an architecturally UNKNOWN value.

Accessing CNTPS_CVAL_EL1

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

MRS <Xt>, CNTPS_CVAL_EL1

op0	op1	CRn	CRm	op2
0b11	0b111	0b1110	0b0010	0b010

if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if HaveEL(EL3) && SCR_EL3.NS == '0' then if SCR_EL3.EEL2 == '1' then UNDEFINED; elsif SCR_EL3.ST == '0' then AArch64.SystemAccessTrap(EL3, 0x18); else X[t, 64] = CNTPS_CVAL_EL1; else UNDEFINED; elsif PSTATE.EL == EL2 then UNDEFINED; elsif PSTATE.EL == EL3 then X[t, 64] = CNTPS_CVAL_EL1;

MSR CNTPS_CVAL_EL1, <Xt>

op0	op1	CRn	CRm	op2
0b11	0b111	0b1110	0b0010	0b010

if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if HaveEL(EL3) && SCR_EL3.NS == '0' then if SCR_EL3.EEL2 == '1' then UNDEFINED; elsif SCR_EL3.ST == '0' then AArch64.SystemAccessTrap(EL3, 0x18); else CNTPS_CVAL_EL1 = X[t, 64]; else UNDEFINED; elsif PSTATE.EL == EL2 then UNDEFINED; elsif PSTATE.EL == EL3 then CNTPS_CVAL_EL1 = X[t, 64];

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
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CompareValue
CompareValue

CNTPS_CVAL_EL1, Counter-timer Physical Secure Timer CompareValue Register