SP_EL2

Holds the stack pointer associated with EL2. When executing at EL2, the value of SPSel. SP determines the current stack pointer:

Configuration

This register has no effect if EL2 is not enabled in the current Security state.

Attributes

Field descriptions

Bits [63:0]

SPSel.SP	Current stack pointer
0b0	SP_EL0
0b1	SP_EL2

Accessing SP_EL2

This accessibility information only applies to accesses using the MRS or MSR instructions.

When the value of SPSel.SP is 1, this register is also accessible at EL2 as the current stack pointer.

Note

When the value of SPSel.SP is 0, SP_EL0 is used as the current stack pointer at all Exception levels.

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

MRS <Xt>, SP_EL2

op0	op1	CRn	CRm	op2
0b11	0b110	0b0100	0b0001	0b000

if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then UNDEFINED; elsif PSTATE.EL == EL2 then UNDEFINED; elsif PSTATE.EL == EL3 then X[t, 64] = SP_EL2;

MSR SP_EL2, <Xt>

op0	op1	CRn	CRm	op2
0b11	0b110	0b0100	0b0001	0b000

if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then UNDEFINED; elsif PSTATE.EL == EL2 then UNDEFINED; elsif PSTATE.EL == EL3 then SP_EL2 = 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
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
Stack pointer
Stack pointer

SP_EL2, Stack Pointer (EL2)