/* SPDX-License-Identifier: BSD-3-Clause */
/*
 * Texas Instruments System Control Interface (TISCI) Protocol
 *
 * Communication protocol with TI SCI hardware
 * The system works in a message response protocol
 * See: http://processors.wiki.ti.com/index.php/TISCI for details
 *
 * Copyright (C)  2018 Texas Instruments Incorporated - http://www.ti.com/
 * Based on drivers/firmware/ti_sci.h from Linux.
 *
 */

#ifndef __TI_SCI_H
#define __TI_SCI_H

/* Generic Messages */
#define TI_SCI_MSG_ENABLE_WDT		0x0000
#define TI_SCI_MSG_WAKE_RESET		0x0001
#define TI_SCI_MSG_VERSION		0x0002
#define TI_SCI_MSG_WAKE_REASON		0x0003
#define TI_SCI_MSG_GOODBYE		0x0004
#define TI_SCI_MSG_SYS_RESET		0x0005
#define TI_SCI_MSG_BOARD_CONFIG		0x000b
#define TI_SCI_MSG_BOARD_CONFIG_RM	0x000c
#define TI_SCI_MSG_BOARD_CONFIG_SECURITY  0x000d
#define TI_SCI_MSG_BOARD_CONFIG_PM	0x000e

/**
 * struct ti_sci_msg_hdr - Generic Message Header for All messages and responses
 * @type:	Type of messages: One of TI_SCI_MSG* values
 * @host:	Host of the message
 * @seq:	Message identifier indicating a transfer sequence
 * @flags:	Flag for the message
 */
struct ti_sci_msg_hdr {
	u16 type;
	u8 host;
	u8 seq;
#define TI_SCI_MSG_FLAG(val)			(1 << (val))
#define TI_SCI_FLAG_REQ_GENERIC_NORESPONSE	0x0
#define TI_SCI_FLAG_REQ_ACK_ON_RECEIVED		TI_SCI_MSG_FLAG(0)
#define TI_SCI_FLAG_REQ_ACK_ON_PROCESSED	TI_SCI_MSG_FLAG(1)
#define TI_SCI_FLAG_RESP_GENERIC_NACK		0x0
#define TI_SCI_FLAG_RESP_GENERIC_ACK		TI_SCI_MSG_FLAG(1)
	/* Additional Flags */
	u32 flags;
} __packed;

/**
 * struct ti_sci_secure_msg_hdr - Header that prefixes all TISCI messages sent
 *				  via secure transport.
 * @checksum:	crc16 checksum for the entire message
 * @reserved:	Reserved for future use.
 */
struct ti_sci_secure_msg_hdr {
	u16 checksum;
	u16 reserved;
} __packed;

/**
 * struct ti_sci_msg_resp_version - Response for a message
 * @hdr:		Generic header
 * @firmware_description: String describing the firmware
 * @firmware_revision:	Firmware revision
 * @abi_major:		Major version of the ABI that firmware supports
 * @abi_minor:		Minor version of the ABI that firmware supports
 *
 * In general, ABI version changes follow the rule that minor version increments
 * are backward compatible. Major revision changes in ABI may not be
 * backward compatible.
 *
 * Response to a generic message with message type TI_SCI_MSG_VERSION
 */
struct ti_sci_msg_resp_version {
	struct ti_sci_msg_hdr hdr;
	char firmware_description[32];
	u16 firmware_revision;
	u8 abi_major;
	u8 abi_minor;
} __packed;

/**
 * struct ti_sci_msg_board_config - Board configuration message
 * @hdr:		Generic Header
 * @boardcfgp_low:	Lower 32 bit of the pointer pointing to the board
 *			configuration data
 * @boardcfgp_high:	Upper 32 bit of the pointer pointing to the board
 *			configuration data
 * @boardcfg_size:	Size of board configuration data object
 * Request type is TI_SCI_MSG_BOARD_CONFIG, responded with a generic
 * ACK/NACK message.
 */
struct ti_sci_msg_board_config {
	struct ti_sci_msg_hdr hdr;
	u32 boardcfgp_low;
	u32 boardcfgp_high;
	u16 boardcfg_size;
} __packed;

#endif /* __TI_SCI_H */