include/linux/arm-smccc.h

/* SPDX-License-Identifier: GPL-2.0 */
/*
 * Copyright (c) 2015, Linaro Limited
 * Copyright 2022-2023 Arm Limited and/or its affiliates <open-source-office@arm.com>
 *
 * Authors:
 *   Abdellatif El Khlifi <abdellatif.elkhlifi@arm.com>
 */
#ifndef __LINUX_ARM_SMCCC_H
#define __LINUX_ARM_SMCCC_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
 */

#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

#define ARM_SMCCC_QUIRK_NONE		0
#define ARM_SMCCC_QUIRK_QCOM_A6		1 /* Save/restore register a6 */

#define ARM_SMCCC_ARCH_FEATURES		0x80000001

#define ARM_SMCCC_RET_NOT_SUPPORTED	((unsigned long)-1)

#ifndef __ASSEMBLY__

#include <linux/linkage.h>
#include <linux/types.h>
/**
 * 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;
};

#ifdef CONFIG_ARM64
/**
 * struct arm_smccc_1_2_regs - Arguments for or Results from SMC call
 * @a0-a17 argument values from registers 0 to 17
 */
struct arm_smccc_1_2_regs {
	unsigned long a0;
	unsigned long a1;
	unsigned long a2;
	unsigned long a3;
	unsigned long a4;
	unsigned long a5;
	unsigned long a6;
	unsigned long a7;
	unsigned long a8;
	unsigned long a9;
	unsigned long a10;
	unsigned long a11;
	unsigned long a12;
	unsigned long a13;
	unsigned long a14;
	unsigned long a15;
	unsigned long a16;
	unsigned long a17;
};

/**
 * arm_smccc_1_2_smc() - make SMC calls
 * @args: arguments passed via struct arm_smccc_1_2_regs
 * @res: result values via struct arm_smccc_1_2_regs
 *
 * This function is used to make SMC calls following SMC Calling Convention
 * v1.2 or above. The content of the supplied param are copied from the
 * structure to registers prior to the SMC instruction. The return values
 * are updated with the content from registers on return from the SMC
 * instruction.
 */
asmlinkage void arm_smccc_1_2_smc(const struct arm_smccc_1_2_regs *args,
				  struct arm_smccc_1_2_regs *res);
#endif

/**
 * struct arm_smccc_quirk - Contains quirk information
 * @id: quirk identification
 * @state: quirk specific information
 * @a6: Qualcomm quirk entry for returning post-smc call contents of a6
 */
struct arm_smccc_quirk {
	int	id;
	union {
		unsigned long a6;
	} state;
};

/**
 * struct arm_smccc_feature - Driver registration data for discoverable feature
 * @driver_name: name of the driver relate to the SMCCC feature
 * @is_supported: callback to test if SMCCC feature is supported
 */
struct arm_smccc_feature {
	const char *driver_name;
	bool (*is_supported)(void (*invoke_fn)(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));
};

#define ARM_SMCCC_FEATURE_DRIVER(__name) \
	ll_entry_declare(struct arm_smccc_feature, __name, arm_smccc_feature)

/**
 * __arm_smccc_smc() - make SMC calls
 * @a0-a7: arguments passed in registers 0 to 7
 * @res: result values from registers 0 to 3
 * @quirk: points to an arm_smccc_quirk, or NULL when no quirks are required.
 *
 * 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.  An optional
 * quirk structure provides vendor specific behavior.
 */
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, struct arm_smccc_quirk *quirk);

/**
 * __arm_smccc_hvc() - make HVC calls
 * @a0-a7: arguments passed in registers 0 to 7
 * @res: result values from registers 0 to 3
 * @quirk: points to an arm_smccc_quirk, or NULL when no quirks are required.
 *
 * 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.  An
 * optional quirk structure provides vendor specific behavior.
 */
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, struct arm_smccc_quirk *quirk);

#define arm_smccc_smc(...) __arm_smccc_smc(__VA_ARGS__, NULL)

#define arm_smccc_smc_quirk(...) __arm_smccc_smc(__VA_ARGS__)

#define arm_smccc_hvc(...) __arm_smccc_hvc(__VA_ARGS__, NULL)

#define arm_smccc_hvc_quirk(...) __arm_smccc_hvc(__VA_ARGS__)

#endif /*__ASSEMBLY__*/
#endif /*__LINUX_ARM_SMCCC_H*/