include/lib/smccc.h

/*
 * Copyright (c) 2016-2020, ARM Limited and Contributors. All rights reserved.
 *
 * SPDX-License-Identifier: BSD-3-Clause
 */

#ifndef SMCCC_H
#define SMCCC_H

#include <lib/utils_def.h>

#define SMCCC_VERSION_MAJOR_SHIFT	U(16)
#define SMCCC_VERSION_MAJOR_MASK	U(0x7FFF)
#define SMCCC_VERSION_MINOR_SHIFT	U(0)
#define SMCCC_VERSION_MINOR_MASK	U(0xFFFF)
#define MAKE_SMCCC_VERSION(_major, _minor) \
	((((uint32_t)(_major) & SMCCC_VERSION_MAJOR_MASK) << \
						SMCCC_VERSION_MAJOR_SHIFT) \
	| (((uint32_t)(_minor) & SMCCC_VERSION_MINOR_MASK) << \
						SMCCC_VERSION_MINOR_SHIFT))

#define SMCCC_MAJOR_VERSION U(1)
#define SMCCC_MINOR_VERSION U(2)

/*******************************************************************************
 * Bit definitions inside the function id as per the SMC calling convention
 ******************************************************************************/
#define FUNCID_TYPE_SHIFT		U(31)
#define FUNCID_TYPE_MASK		U(0x1)
#define FUNCID_TYPE_WIDTH		U(1)

#define FUNCID_CC_SHIFT			U(30)
#define FUNCID_CC_MASK			U(0x1)
#define FUNCID_CC_WIDTH			U(1)

#define FUNCID_OEN_SHIFT		U(24)
#define FUNCID_OEN_MASK			U(0x3f)
#define FUNCID_OEN_WIDTH		U(6)

#define FUNCID_NUM_SHIFT		U(0)
#define FUNCID_NUM_MASK			U(0xffff)
#define FUNCID_NUM_WIDTH		U(16)

#define GET_SMC_NUM(id)			(((id) >> FUNCID_NUM_SHIFT) & \
					 FUNCID_NUM_MASK)
#define GET_SMC_TYPE(id)		(((id) >> FUNCID_TYPE_SHIFT) & \
					 FUNCID_TYPE_MASK)
#define GET_SMC_CC(id)			(((id) >> FUNCID_CC_SHIFT) & \
					 FUNCID_CC_MASK)
#define GET_SMC_OEN(id)			(((id) >> FUNCID_OEN_SHIFT) & \
					 FUNCID_OEN_MASK)

/*******************************************************************************
 * Owning entity number definitions inside the function id as per the SMC
 * calling convention
 ******************************************************************************/
#define OEN_ARM_START			U(0)
#define OEN_ARM_END			U(0)
#define OEN_CPU_START			U(1)
#define OEN_CPU_END			U(1)
#define OEN_SIP_START			U(2)
#define OEN_SIP_END			U(2)
#define OEN_OEM_START			U(3)
#define OEN_OEM_END			U(3)
#define OEN_STD_START			U(4)	/* Standard Service Calls */
#define OEN_STD_END			U(4)
#define OEN_STD_HYP_START		U(5)	/* Standard Hypervisor Service calls */
#define OEN_STD_HYP_END			U(5)
#define OEN_VEN_HYP_START		U(6)	/* Vendor Hypervisor Service calls */
#define OEN_VEN_HYP_END			U(6)
#define OEN_TAP_START			U(48)	/* Trusted Applications */
#define OEN_TAP_END			U(49)
#define OEN_TOS_START			U(50)	/* Trusted OS */
#define OEN_TOS_END			U(63)
#define OEN_LIMIT			U(64)

/* Flags and error codes */
#define SMC_64				U(1)
#define SMC_32				U(0)

#define SMC_TYPE_FAST			ULL(1)
#define SMC_TYPE_YIELD			ULL(0)

#define SMC_OK				ULL(0)
#define SMC_UNK				-1
#define SMC_PREEMPTED			-2	/* Not defined by the SMCCC */

/* Return codes for Arm Architecture Service SMC calls */
#define SMC_ARCH_CALL_SUCCESS		0
#define SMC_ARCH_CALL_NOT_SUPPORTED	-1
#define SMC_ARCH_CALL_NOT_REQUIRED	-2
#define SMC_ARCH_CALL_INVAL_PARAM	-3

/* Various flags passed to SMC handlers */
#define SMC_FROM_SECURE		(U(0) << 0)
#define SMC_FROM_NON_SECURE	(U(1) << 0)

#ifndef __ASSEMBLER__

#include <stdint.h>

#include <lib/cassert.h>

#define is_caller_non_secure(_f)	(((_f) & SMC_FROM_NON_SECURE) != U(0))
#define is_caller_secure(_f)		(!is_caller_non_secure(_f))

/* The macro below is used to identify a Standard Service SMC call */
#define is_std_svc_call(_fid)		(GET_SMC_OEN(_fid) == OEN_STD_START)

/* The macro below is used to identify a Arm Architectural Service SMC call */
#define is_arm_arch_svc_call(_fid)	(GET_SMC_OEN(_fid) == OEN_ARM_START)

/* The macro below is used to identify a valid Fast SMC call */
#define is_valid_fast_smc(_fid)		((!(((_fid) >> 16) & U(0xff))) && \
					   (GET_SMC_TYPE(_fid) == SMC_TYPE_FAST))

/*
 * Macro to define UUID for services. Apart from defining and initializing a
 * uuid_t structure, this macro verifies that the first word of the defined UUID
 * does not equal SMC_UNK. This is to ensure that the caller won't mistake the
 * returned UUID in x0 for an invalid SMC error return
 */
#define DEFINE_SVC_UUID2(_name, _tl, _tm, _th, _cl, _ch,		\
		_n0, _n1, _n2, _n3, _n4, _n5)				\
	CASSERT((uint32_t)(_tl) != (uint32_t)SMC_UNK,			\
		invalid_svc_uuid_##_name);				\
	static const uuid_t _name = {					\
		{((_tl) >> 24) & 0xFF,					\
		 ((_tl) >> 16) & 0xFF,					\
		 ((_tl) >> 8)  & 0xFF,					\
		 ((_tl) & 0xFF)},					\
		{((_tm) >> 8) & 0xFF,					\
		 ((_tm)  & 0xFF)},					\
		{((_th) >> 8) & 0xFF,					\
		 ((_th) & 0xFF)},					\
		(_cl), (_ch),						\
		{ (_n0), (_n1), (_n2), (_n3), (_n4), (_n5) }		\
	}

/*
 * Return a UUID in the SMC return registers.
 *
 * Acccording to section 5.3 of the SMCCC, UUIDs are returned as a single
 * 128-bit value using the SMC32 calling convention. This value is mapped to
 * argument registers x0-x3 on AArch64 (resp. r0-r3 on AArch32). x0 for example
 * shall hold bytes 0 to 3, with byte 0 in the low-order bits.
 */
static inline uint32_t smc_uuid_word(uint8_t b0, uint8_t b1, uint8_t b2, uint8_t b3)
{
	return ((uint32_t) b0) | (((uint32_t) b1) << 8) |
		(((uint32_t) b2) << 16) | (((uint32_t) b3) << 24);
}

#define SMC_UUID_RET(_h, _uuid)							\
	SMC_RET4(handle,							\
		smc_uuid_word((_uuid).time_low[0], (_uuid).time_low[1],		\
			      (_uuid).time_low[2], (_uuid).time_low[3]),	\
		smc_uuid_word((_uuid).time_mid[0], (_uuid).time_mid[1],		\
			      (_uuid).time_hi_and_version[0],			\
			      (_uuid).time_hi_and_version[1]),			\
		smc_uuid_word((_uuid).clock_seq_hi_and_reserved,		\
			      (_uuid).clock_seq_low, (_uuid).node[0],		\
			      (_uuid).node[1]),					\
		smc_uuid_word((_uuid).node[2], (_uuid).node[3],			\
			      (_uuid).node[4], (_uuid).node[5]))

#endif /*__ASSEMBLER__*/
#endif /* SMCCC_H */