/*
 * Copyright (c) 2015, Linaro Limited
 *
 * This software is licensed under the terms of the GNU General Public
 * License version 2, as published by the Free Software Foundation, and
 * may be copied, distributed, and modified under those terms.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 */
#ifndef __LINUX_ARM_SMCCC_H
#define __LINUX_ARM_SMCCC_H

#include <linux/linkage.h>
#include <linux/types.h>

/*
 * This file provides common defines for ARM SMC Calling Convention as
 * specified in
 * http://infocenter.arm.com/help/topic/com.arm.doc.den0028a/index.html
 */

/* This constant is shifted by 31, make sure it's of an unsigned type */
#define ARM_SMCCC_STD_CALL		0UL
#define ARM_SMCCC_FAST_CALL		1UL
#define ARM_SMCCC_TYPE_SHIFT		31

#define ARM_SMCCC_SMC_32		0
#define ARM_SMCCC_SMC_64		1
#define ARM_SMCCC_CALL_CONV_SHIFT	30

#define ARM_SMCCC_OWNER_MASK		0x3F
#define ARM_SMCCC_OWNER_SHIFT		24

#define ARM_SMCCC_FUNC_MASK		0xFFFF

#define ARM_SMCCC_IS_FAST_CALL(smc_val)	\
	((smc_val) & (ARM_SMCCC_FAST_CALL << ARM_SMCCC_TYPE_SHIFT))
#define ARM_SMCCC_IS_64(smc_val) \
	((smc_val) & (ARM_SMCCC_SMC_64 << ARM_SMCCC_CALL_CONV_SHIFT))
#define ARM_SMCCC_FUNC_NUM(smc_val)	((smc_val) & ARM_SMCCC_FUNC_MASK)
#define ARM_SMCCC_OWNER_NUM(smc_val) \
	(((smc_val) >> ARM_SMCCC_OWNER_SHIFT) & ARM_SMCCC_OWNER_MASK)

#define ARM_SMCCC_CALL_VAL(type, calling_convention, owner, func_num) \
	(((type) << ARM_SMCCC_TYPE_SHIFT) | \
	((calling_convention) << ARM_SMCCC_CALL_CONV_SHIFT) | \
	(((owner) & ARM_SMCCC_OWNER_MASK) << ARM_SMCCC_OWNER_SHIFT) | \
	((func_num) & ARM_SMCCC_FUNC_MASK))

#define ARM_SMCCC_OWNER_ARCH		0
#define ARM_SMCCC_OWNER_CPU		1
#define ARM_SMCCC_OWNER_SIP		2
#define ARM_SMCCC_OWNER_OEM		3
#define ARM_SMCCC_OWNER_STANDARD	4
#define ARM_SMCCC_OWNER_TRUSTED_APP	48
#define ARM_SMCCC_OWNER_TRUSTED_APP_END	49
#define ARM_SMCCC_OWNER_TRUSTED_OS	50
#define ARM_SMCCC_OWNER_TRUSTED_OS_END	63

/**
 * struct arm_smccc_res - Result from SMC/HVC call
 * @a0-a3 result values from registers 0 to 3
 */
struct arm_smccc_res {
	unsigned long a0;
	unsigned long a1;
	unsigned long a2;
	unsigned long a3;
};

/**
 * arm_smccc_smc() - make SMC calls
 * @a0-a7: arguments passed in registers 0 to 7
 * @res: result values from registers 0 to 3
 *
 * This function is used to make SMC calls following SMC Calling Convention.
 * The content of the supplied param are copied to registers 0 to 7 prior
 * to the SMC instruction. The return values are updated with the content
 * from register 0 to 3 on return from the SMC instruction.
 */
asmlinkage void arm_smccc_smc(unsigned long a0, unsigned long a1,
			unsigned long a2, unsigned long a3, unsigned long a4,
			unsigned long a5, unsigned long a6, unsigned long a7,
			struct arm_smccc_res *res);

/**
 * arm_smccc_hvc() - make HVC calls
 * @a0-a7: arguments passed in registers 0 to 7
 * @res: result values from registers 0 to 3
 *
 * This function is used to make HVC calls following SMC Calling
 * Convention.  The content of the supplied param are copied to registers 0
 * to 7 prior to the HVC instruction. The return values are updated with
 * the content from register 0 to 3 on return from the HVC instruction.
 */
asmlinkage void arm_smccc_hvc(unsigned long a0, unsigned long a1,
			unsigned long a2, unsigned long a3, unsigned long a4,
			unsigned long a5, unsigned long a6, unsigned long a7,
			struct arm_smccc_res *res);

#endif /*__LINUX_ARM_SMCCC_H*/