xref: /aosp_15_r20/trusty/kernel/lib/smc/arch/arm64/smc.S (revision 344aa361028b423587d4ef3fa52a23d194628137)

/*
 * Copyright (c) 2020, Google Inc. All rights reserved
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files
 * (the "Software"), to deal in the Software without restriction,
 * including without limitation the rights to use, copy, modify, merge,
 * publish, distribute, sublicense, and/or sell copies of the Software,
 * and to permit persons to whom the Software is furnished to do so,
 * subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
 * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

#include <asm.h>
#include <arch/asm_macros.h>

.macro smc8_hvc8, instr
    /*
     * Save x8 (return value ptr) and lr. The SMC calling convention says el3
     * does not need to preserve x8. The normal ABI does not require either x8
     * or lr to be preserved.
     */
    push    x8, lr
    \instr  #0
    pop     x8, lr

    /* Copy 8-register smc return value to struct smc_ret8 return value */
    stp     x0, x1, [x8], #16
    stp     x2, x3, [x8], #16
    stp     x4, x5, [x8], #16
    stp     x6, x7, [x8], #16

    ret
.endm

FUNCTION(smc8)
    smc8_hvc8 smc

FUNCTION(hvc8)
    smc8_hvc8 hvc