plat/arm/css/drivers/scmi/scmi_private.h

/*
 * Copyright (c) 2017, ARM Limited and Contributors. All rights reserved.
 *
 * SPDX-License-Identifier: BSD-3-Clause
 */

#ifndef __CSS_SCMI_PRIVATE_H__
#define __CSS_SCMI_PRIVATE_H__

/*
 * SCMI power domain management protocol message and response lengths. It is
 * calculated as sum of length in bytes of the message header (4) and payload
 * area (the number of bytes of parameters or return values in the payload).
 */
#define SCMI_PROTO_VERSION_MSG_LEN		4
#define SCMI_PROTO_VERSION_RESP_LEN		12

#define SCMI_PROTO_MSG_ATTR_MSG_LEN		8
#define SCMI_PROTO_MSG_ATTR_RESP_LEN		12

#define SCMI_PWR_STATE_SET_MSG_LEN		16
#define SCMI_PWR_STATE_SET_RESP_LEN		8

#define SCMI_PWR_STATE_GET_MSG_LEN		8
#define SCMI_PWR_STATE_GET_RESP_LEN		12

#define SCMI_SYS_PWR_STATE_SET_MSG_LEN		12
#define SCMI_SYS_PWR_STATE_SET_RESP_LEN		8

#define SCMI_SYS_PWR_STATE_GET_MSG_LEN		4
#define SCMI_SYS_PWR_STATE_GET_RESP_LEN		12

/* SCMI message header format bit field */
#define SCMI_MSG_ID_SHIFT		0
#define SCMI_MSG_ID_WIDTH		8
#define SCMI_MSG_ID_MASK		((1 << SCMI_MSG_ID_WIDTH) - 1)

#define SCMI_MSG_TYPE_SHIFT		8
#define SCMI_MSG_TYPE_WIDTH		2
#define SCMI_MSG_TYPE_MASK		((1 << SCMI_MSG_TYPE_WIDTH) - 1)

#define SCMI_MSG_PROTO_ID_SHIFT		10
#define SCMI_MSG_PROTO_ID_WIDTH		8
#define SCMI_MSG_PROTO_ID_MASK		((1 << SCMI_MSG_PROTO_ID_WIDTH) - 1)

#define SCMI_MSG_TOKEN_SHIFT		18
#define SCMI_MSG_TOKEN_WIDTH		10
#define SCMI_MSG_TOKEN_MASK		((1 << SCMI_MSG_TOKEN_WIDTH) - 1)


/* SCMI mailbox flags */
#define SCMI_FLAG_RESP_POLL	0
#define SCMI_FLAG_RESP_INT	1

/* SCMI power domain protocol `POWER_STATE_SET` message flags */
#define SCMI_PWR_STATE_SET_FLAG_SYNC	0
#define SCMI_PWR_STATE_SET_FLAG_ASYNC	1

/*
 * Helper macro to create an SCMI message header given protocol, message id
 * and token.
 */
#define SCMI_MSG_CREATE(protocol, msg_id, token)				\
	((((protocol) & SCMI_MSG_PROTO_ID_MASK) << SCMI_MSG_PROTO_ID_SHIFT) |	\
	(((msg_id) & SCMI_MSG_ID_MASK) << SCMI_MSG_ID_SHIFT) |			\
	(((token) & SCMI_MSG_TOKEN_MASK) << SCMI_MSG_TOKEN_SHIFT))

/* Helper macro to get the token from a SCMI message header */
#define SCMI_MSG_GET_TOKEN(msg)				\
	(((msg) >> SCMI_MSG_TOKEN_SHIFT) & SCMI_MSG_TOKEN_MASK)

/* SCMI Channel Status bit fields */
#define SCMI_CH_STATUS_RES0_MASK	0xFFFFFFFE
#define SCMI_CH_STATUS_FREE_SHIFT	0
#define SCMI_CH_STATUS_FREE_WIDTH	1
#define SCMI_CH_STATUS_FREE_MASK	((1 << SCMI_CH_STATUS_FREE_WIDTH) - 1)

/* Helper macros to check and write the channel status */
#define SCMI_IS_CHANNEL_FREE(status)					\
	(!!(((status) >> SCMI_CH_STATUS_FREE_SHIFT) & SCMI_CH_STATUS_FREE_MASK))

#define SCMI_MARK_CHANNEL_BUSY(status)	do {				\
		assert(SCMI_IS_CHANNEL_FREE(status));			\
		(status) &= ~(SCMI_CH_STATUS_FREE_MASK <<		\
				SCMI_CH_STATUS_FREE_SHIFT);		\
	} while (0)

/* Helper macros to copy arguments to the mailbox payload */
#define SCMI_PAYLOAD_ARG1(payld_arr, arg1)				\
		mmio_write_32((uintptr_t)&payld_arr[0], arg1)

#define SCMI_PAYLOAD_ARG2(payld_arr, arg1, arg2)	do {		\
		SCMI_PAYLOAD_ARG1(payld_arr, arg1);			\
		mmio_write_32((uintptr_t)&payld_arr[1], arg2);		\
	} while (0)

#define SCMI_PAYLOAD_ARG3(payld_arr, arg1, arg2, arg3)	do {		\
		SCMI_PAYLOAD_ARG2(payld_arr, arg1, arg2);		\
		mmio_write_32((uintptr_t)&payld_arr[2], arg3);		\
	} while (0)

/* Helper macros to read return values from the mailbox payload */
#define SCMI_PAYLOAD_RET_VAL1(payld_arr, val1)				\
		(val1) = mmio_read_32((uintptr_t)&payld_arr[0])

#define SCMI_PAYLOAD_RET_VAL2(payld_arr, val1, val2)	do {		\
		SCMI_PAYLOAD_RET_VAL1(payld_arr, val1);			\
		(val2) = mmio_read_32((uintptr_t)&payld_arr[1]);	\
	} while (0)

#define SCMI_PAYLOAD_RET_VAL3(payld_arr, val1, val2, val3)	do {	\
		SCMI_PAYLOAD_RET_VAL2(payld_arr, val1, val2);		\
		(val3) = mmio_read_32((uintptr_t)&payld_arr[2]);	\
	} while (0)

/* Helper macro to ring doorbell */
#define SCMI_RING_DOORBELL(addr, modify_mask, preserve_mask)	do {	\
		uint32_t db = mmio_read_32(addr) & (preserve_mask);	\
		mmio_write_32(addr, db | (modify_mask));		\
	} while (0)

/*
 * Private data structure for representing the mailbox memory layout. Refer
 * the SCMI specification for more details.
 */
typedef struct mailbox_mem {
	uint32_t res_a; /* Reserved */
	volatile uint32_t status;
	uint64_t res_b; /* Reserved */
	uint32_t flags;
	volatile uint32_t len;
	uint32_t msg_header;
	uint32_t payload[];
} mailbox_mem_t;


/* Private APIs for use within SCMI driver */
void scmi_get_channel(scmi_channel_t *ch);
void scmi_send_sync_command(scmi_channel_t *ch);
void scmi_put_channel(scmi_channel_t *ch);

static inline void validate_scmi_channel(scmi_channel_t *ch)
{
	assert(ch && ch->is_initialized);
	assert(ch->info && ch->info->scmi_mbx_mem);
}

#endif	/* __CSS_SCMI_PRIVATE_H__ */