Hypercall

1 Instruction

XenSwdgn~arm64_hyp_instr~1

Description: Xen shall treat domain hvc instruction execution (with 0xEA1) as hypercall requests.

Rationale:

Comments: Hypercall is one of the communication mechanism between Xen and domains. Domains use hypercalls for various requests to Xen. The exception syndrome register should have the following values :-ESR_EL2.ISS should be 0xEA1. ESR_EL2.EC should be 0x16.

Covers:

2 Parameters

XenSwdgn~arm64_hyp_param~1

Description: Xen shall use x0 - x4 core registers to obtain the arguments for domain hypercall requests.

Rationale:

Comments: Xen shall read x0 for the first argument, x1 for the second argument and so on.

Covers:

3 Hypercall number

XenSwdgn~arm64_hyp_num~1

Description: Xen shall read x16 to obtain the hypercall number.

Rationale:

Comments:

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4 Return value

XenSwdgn~arm64_ret_val~1

Description: Xen shall store the return value in x0.

Rationale:

Comments:

Covers: