/* SPDX-License-Identifier: GPL-2.0 */
/*
 * Copyright(c) 2016-20 Intel Corporation.
 */

        .macro ENCLU
        .byte 0x0f, 0x01, 0xd7
        .endm

        .section ".tcs", "aw"
        .balign 4096

        .fill   1, 8, 0                 # STATE (set by CPU)
        .fill   1, 8, 0                 # FLAGS
        .quad   encl_ssa_tcs1           # OSSA
        .fill   1, 4, 0                 # CSSA (set by CPU)
        .fill   1, 4, 1                 # NSSA
        .quad   encl_entry              # OENTRY
        .fill   1, 8, 0                 # AEP (set by EENTER and ERESUME)
        .fill   1, 8, 0                 # OFSBASE
        .fill   1, 8, 0                 # OGSBASE
        .fill   1, 4, 0xFFFFFFFF        # FSLIMIT
        .fill   1, 4, 0xFFFFFFFF        # GSLIMIT
        .fill   4024, 1, 0              # Reserved

        # TCS2
        .fill   1, 8, 0                 # STATE (set by CPU)
        .fill   1, 8, 0                 # FLAGS
        .quad   encl_ssa_tcs2           # OSSA
        .fill   1, 4, 0                 # CSSA (set by CPU)
        .fill   1, 4, 1                 # NSSA
        .quad   encl_entry              # OENTRY
        .fill   1, 8, 0                 # AEP (set by EENTER and ERESUME)
        .fill   1, 8, 0                 # OFSBASE
        .fill   1, 8, 0                 # OGSBASE
        .fill   1, 4, 0xFFFFFFFF        # FSLIMIT
        .fill   1, 4, 0xFFFFFFFF        # GSLIMIT
        .fill   4024, 1, 0              # Reserved

        .text

encl_entry:
        # RBX contains the base address for TCS, which is the first address
        # inside the enclave for TCS #1 and one page into the enclave for
        # TCS #2. First make it relative by substracting __encl_base and
        # then add the address of encl_stack to get the address for the stack.
        lea __encl_base(%rip), %rax
        sub %rax, %rbx
        lea encl_stack(%rip), %rax
        add %rbx, %rax
        jmp encl_entry_core
encl_dyn_entry:
        # Entry point for dynamically created TCS page expected to follow
        # its stack directly.
        lea -1(%rbx), %rax
encl_entry_core:
        xchg    %rsp, %rax
        push    %rax

        push    %rcx # push the address after EENTER

        # NOTE: as the selftest enclave is *not* intended for production,
        # simplify the code by not initializing ABI registers on entry or
        # cleansing caller-save registers on exit.
        call    encl_body

        # Prepare EEXIT target by popping the address of the instruction after
        # EENTER to RBX.
        pop     %rbx

        # Restore the caller stack.
        pop     %rax
        mov     %rax, %rsp

        # EEXIT
        mov     $4, %rax
        enclu

        .section ".data", "aw"

encl_ssa_tcs1:
        .space 4096
encl_ssa_tcs2:
        .space 4096

        .balign 4096
        # Stack of TCS #1
        .space 4096
encl_stack:
        .balign 4096
        # Stack of TCS #2
        .space 4096