The SP_EL0 characteristics are:
Holds the stack pointer associated with EL0. At higher Exception levels, this is used as the current stack pointer when the value of SPSel.SP is 0.
There are no configuration notes.
SP_EL0 is a 64-bit register.
The SP_EL0 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 |
Stack pointer | |||||||||||||||||||||||||||||||
Stack pointer | |||||||||||||||||||||||||||||||
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.
On a Warm reset, this field resets to an architecturally UNKNOWN value.
When the value of PSTATE.SP is 0, this register is accessible at all Exception levels as the current stack pointer.
Accesses to this register use the following encodings:
op0 | op1 | CRn | CRm | op2 |
---|---|---|---|---|
0b11 | 0b000 | 0b0100 | 0b0001 | 0b000 |
if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if PSTATE.SP == '0' then UNDEFINED; else return SP_EL0; elsif PSTATE.EL == EL2 then if PSTATE.SP == '0' then UNDEFINED; else return SP_EL0; elsif PSTATE.EL == EL3 then if PSTATE.SP == '0' then UNDEFINED; else return SP_EL0;
op0 | op1 | CRn | CRm | op2 |
---|---|---|---|---|
0b11 | 0b000 | 0b0100 | 0b0001 | 0b000 |
if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if PSTATE.SP == '0' then UNDEFINED; else SP_EL0 = X[t]; elsif PSTATE.EL == EL2 then if PSTATE.SP == '0' then UNDEFINED; else SP_EL0 = X[t]; elsif PSTATE.EL == EL3 then if PSTATE.SP == '0' then UNDEFINED; else SP_EL0 = X[t];
30/09/2020 15:07; ccead0cb9f089f9ceec50268e82aec9e71047211
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