/*
 * Copyright 2019 The Hafnium Authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include "smc.h"

#include <stdint.h>

static struct smc_result smc_internal(uint32_t func, uint64_t arg0,
				      uint64_t arg1, uint64_t arg2,
				      uint64_t arg3, uint64_t arg4,
				      uint64_t arg5, uint32_t caller_id)
{
	register uint64_t r0 __asm__("x0") = func;
	register uint64_t r1 __asm__("x1") = arg0;
	register uint64_t r2 __asm__("x2") = arg1;
	register uint64_t r3 __asm__("x3") = arg2;
	register uint64_t r4 __asm__("x4") = arg3;
	register uint64_t r5 __asm__("x5") = arg4;
	register uint64_t r6 __asm__("x6") = arg5;
	register uint64_t r7 __asm__("x7") = caller_id;

	__asm__ volatile(
		"smc #0"
		: /* Output registers, also used as inputs ('+' constraint). */
		"+r"(r0), "+r"(r1), "+r"(r2), "+r"(r3), "+r"(r4), "+r"(r5),
		"+r"(r6), "+r"(r7));

	return (struct smc_result){.res0 = r0,
				   .res1 = r1,
				   .res2 = r2,
				   .res3 = r3,
				   .res4 = r4,
				   .res5 = r5,
				   .res6 = r6,
				   .res7 = r7};
}

struct smc_result smc32(uint32_t func, uint32_t arg0, uint32_t arg1,
			uint32_t arg2, uint32_t arg3, uint32_t arg4,
			uint32_t arg5, uint32_t caller_id)
{
	return smc_internal(func | SMCCC_32_BIT, arg0, arg1, arg2, arg3, arg4,
			    arg5, caller_id);
}

struct smc_result smc64(uint32_t func, uint64_t arg0, uint64_t arg1,
			uint64_t arg2, uint64_t arg3, uint64_t arg4,
			uint64_t arg5, uint32_t caller_id)
{
	return smc_internal(func | SMCCC_64_BIT, arg0, arg1, arg2, arg3, arg4,
			    arg5, caller_id);
}

struct smc_result smc_forward(uint32_t func, uint64_t arg0, uint64_t arg1,
			      uint64_t arg2, uint64_t arg3, uint64_t arg4,
			      uint64_t arg5, uint32_t caller_id)
{
	return smc_internal(func, arg0, arg1, arg2, arg3, arg4, arg5,
			    caller_id);
}