// SPDX-License-Identifier: (GPL-2.0-only OR BSD-3-Clause)
//
// This file is provided under a dual BSD/GPLv2 license.  When using or
// redistributing this file, you may do so under either license.
//
// Copyright(c) 2018 Intel Corporation. All rights reserved.
//
// Author: Liam Girdwood <liam.r.girdwood@linux.intel.com>
//
// Generic IPC layer that can work over MMIO and SPI/I2C. PHY layer provided
// by platform driver code.
//

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

#include "sof-priv.h"
#include "sof-audio.h"
#include "ops.h"

/**
 * sof_ipc_send_msg - generic function to prepare and send one IPC message
 * @sdev:		pointer to SOF core device struct
 * @msg_data:		pointer to a message to send
 * @msg_bytes:		number of bytes in the message
 * @reply_bytes:	number of bytes available for the reply.
 *			The buffer for the reply data is not passed to this
 *			function, the available size is an information for the
 *			reply handling functions.
 *
 * On success the function returns 0, otherwise negative error number.
 *
 * Note: higher level sdev->ipc->tx_mutex must be held to make sure that
 *	 transfers are synchronized.
 */
int sof_ipc_send_msg(struct snd_sof_dev *sdev, void *msg_data, size_t msg_bytes,
		     size_t reply_bytes)
{
	struct snd_sof_ipc *ipc = sdev->ipc;
	struct snd_sof_ipc_msg *msg;
	int ret;

	if (ipc->disable_ipc_tx || sdev->fw_state != SOF_FW_BOOT_COMPLETE)
		return -ENODEV;

	/*
	 * The spin-lock is needed to protect message objects against other
	 * atomic contexts.
	 */
	spin_lock_irq(&sdev->ipc_lock);

	/* initialise the message */
	msg = &ipc->msg;

	/* attach message data */
	msg->msg_data = msg_data;
	msg->msg_size = msg_bytes;

	msg->reply_size = reply_bytes;
	msg->reply_error = 0;

	sdev->msg = msg;

	ret = snd_sof_dsp_send_msg(sdev, msg);
	/* Next reply that we receive will be related to this message */
	if (!ret)
		msg->ipc_complete = false;

	spin_unlock_irq(&sdev->ipc_lock);

	return ret;
}

/* send IPC message from host to DSP */
int sof_ipc_tx_message(struct snd_sof_ipc *ipc, void *msg_data, size_t msg_bytes,
		       void *reply_data, size_t reply_bytes)
{
	if (msg_bytes > ipc->max_payload_size ||
	    reply_bytes > ipc->max_payload_size)
		return -ENOBUFS;

	return ipc->ops->tx_msg(ipc->sdev, msg_data, msg_bytes, reply_data,
				reply_bytes, false);
}
EXPORT_SYMBOL(sof_ipc_tx_message);

/*
 * send IPC message from host to DSP without modifying the DSP state.
 * This will be used for IPC's that can be handled by the DSP
 * even in a low-power D0 substate.
 */
int sof_ipc_tx_message_no_pm(struct snd_sof_ipc *ipc, void *msg_data, size_t msg_bytes,
			     void *reply_data, size_t reply_bytes)
{
	if (msg_bytes > ipc->max_payload_size ||
	    reply_bytes > ipc->max_payload_size)
		return -ENOBUFS;

	return ipc->ops->tx_msg(ipc->sdev, msg_data, msg_bytes, reply_data,
				reply_bytes, true);
}
EXPORT_SYMBOL(sof_ipc_tx_message_no_pm);

/* Generic helper function to retrieve the reply */
void snd_sof_ipc_get_reply(struct snd_sof_dev *sdev)
{
	/*
	 * Sometimes, there is unexpected reply ipc arriving. The reply
	 * ipc belongs to none of the ipcs sent from driver.
	 * In this case, the driver must ignore the ipc.
	 */
	if (!sdev->msg) {
		dev_warn(sdev->dev, "unexpected ipc interrupt raised!\n");
		return;
	}

	sdev->msg->reply_error = sdev->ipc->ops->get_reply(sdev);
}
EXPORT_SYMBOL(snd_sof_ipc_get_reply);

/* handle reply message from DSP */
void snd_sof_ipc_reply(struct snd_sof_dev *sdev, u32 msg_id)
{
	struct snd_sof_ipc_msg *msg = &sdev->ipc->msg;

	if (msg->ipc_complete) {
		dev_dbg(sdev->dev,
			"no reply expected, received 0x%x, will be ignored",
			msg_id);
		return;
	}

	/* wake up and return the error if we have waiters on this message ? */
	msg->ipc_complete = true;
	wake_up(&msg->waitq);
}
EXPORT_SYMBOL(snd_sof_ipc_reply);

struct snd_sof_ipc *snd_sof_ipc_init(struct snd_sof_dev *sdev)
{
	struct snd_sof_ipc *ipc;
	struct snd_sof_ipc_msg *msg;
	const struct sof_ipc_ops *ops;

	ipc = devm_kzalloc(sdev->dev, sizeof(*ipc), GFP_KERNEL);
	if (!ipc)
		return NULL;

	mutex_init(&ipc->tx_mutex);
	ipc->sdev = sdev;
	msg = &ipc->msg;

	/* indicate that we aren't sending a message ATM */
	msg->ipc_complete = true;

	init_waitqueue_head(&msg->waitq);

	/*
	 * Use IPC3 ops as it is the only available version now. With the addition of new IPC
	 * versions, this will need to be modified to use the selected version at runtime.
	 */
	ipc->ops = &ipc3_ops;
	ops = ipc->ops;

	/* check for mandatory ops */
	if (!ops->tx_msg || !ops->rx_msg || !ops->set_get_data || !ops->get_reply) {
		dev_err(sdev->dev, "Missing IPC message handling ops\n");
		return NULL;
	}

	if (!ops->fw_loader || !ops->fw_loader->validate ||
	    !ops->fw_loader->parse_ext_manifest) {
		dev_err(sdev->dev, "Missing IPC firmware loading ops\n");
		return NULL;
	}

	if (!ops->pcm) {
		dev_err(sdev->dev, "Missing IPC PCM ops\n");
		return NULL;
	}

	if (!ops->tplg || !ops->tplg->widget || !ops->tplg->control) {
		dev_err(sdev->dev, "Missing IPC topology ops\n");
		return NULL;
	}

	return ipc;
}
EXPORT_SYMBOL(snd_sof_ipc_init);

void snd_sof_ipc_free(struct snd_sof_dev *sdev)
{
	struct snd_sof_ipc *ipc = sdev->ipc;

	if (!ipc)
		return;

	/* disable sending of ipc's */
	mutex_lock(&ipc->tx_mutex);
	ipc->disable_ipc_tx = true;
	mutex_unlock(&ipc->tx_mutex);
}
EXPORT_SYMBOL(snd_sof_ipc_free);