drivers/mailbox/k3-sec-proxy.c - platform/external/u-boot - Gitiles

 // SPDX-License-Identifier: GPL-2.0+
 /*
  * Texas Instruments' K3 Secure proxy Driver
  *
  * Copyright (C) 2017-2018 Texas Instruments Incorporated - http://www.ti.com/
  *	Lokesh Vutla <lokeshvutla@ti.com>
  */

 #include <common.h>
 #include <log.h>
 #include <malloc.h>
 #include <asm/io.h>
 #include <dm/device_compat.h>
 #include <linux/types.h>
 #include <linux/bitops.h>
 #include <linux/soc/ti/k3-sec-proxy.h>
 #include <dm.h>
 #include <mailbox-uclass.h>

 DECLARE_GLOBAL_DATA_PTR;

 /* SEC PROXY RT THREAD STATUS */
 #define RT_THREAD_STATUS			0x0
 #define RT_THREAD_THRESHOLD			0x4
 #define RT_THREAD_STATUS_ERROR_SHIFT		31
 #define RT_THREAD_STATUS_ERROR_MASK		BIT(31)
 #define RT_THREAD_STATUS_CUR_CNT_SHIFT		0
 #define RT_THREAD_STATUS_CUR_CNT_MASK		GENMASK(7, 0)

 /* SEC PROXY SCFG THREAD CTRL */
 #define SCFG_THREAD_CTRL			0x1000
 #define SCFG_THREAD_CTRL_DIR_SHIFT		31
 #define SCFG_THREAD_CTRL_DIR_MASK		BIT(31)

 #define SEC_PROXY_THREAD(base, x)		((base) + (0x1000 * (x)))
 #define THREAD_IS_RX				1
 #define THREAD_IS_TX				0

 /**
  * struct k3_sec_proxy_desc - Description of secure proxy integration.
  * @thread_count:	Number of Threads.
  * @max_msg_size:	Message size in bytes.
  * @data_start_offset:	Offset of the First data register of the thread
  * @data_end_offset:	Offset of the Last data register of the thread
  * @valid_threads:	List of Valid threads that the processor can access
  * @num_valid_threads:	Number of valid threads.
  */
 struct k3_sec_proxy_desc {
 	u16 thread_count;
 	u16 max_msg_size;
 	u16 data_start_offset;
 	u16 data_end_offset;
 	const u32 *valid_threads;
 	u32 num_valid_threads;
 };

 /**
  * struct k3_sec_proxy_thread - Description of a secure proxy Thread
  * @id:		Thread ID
  * @data:	Thread Data path region for target
  * @scfg:	Secure Config Region for Thread
  * @rt:		RealTime Region for Thread
  * @rx_buf:	Receive buffer data, max message size.
  */
 struct k3_sec_proxy_thread {
 	u32 id;
 	void __iomem *data;
 	void __iomem *scfg;
 	void __iomem *rt;
 	u32 *rx_buf;
 };

 /**
  * struct k3_sec_proxy_mbox - Description of a Secure Proxy Instance
  * @chan:		Mailbox Channel
  * @desc:		Description of the SoC integration
  * @chans:		Array for valid thread instances
  * @target_data:	Secure Proxy region for Target Data
  * @scfg:		Secure Proxy Region for Secure configuration.
  * @rt:			Secure proxy Region for Real Time Region.
  */
 struct k3_sec_proxy_mbox {
 	struct mbox_chan chan;
 	struct k3_sec_proxy_desc *desc;
 	struct k3_sec_proxy_thread *chans;
 	phys_addr_t target_data;
 	phys_addr_t scfg;
 	phys_addr_t rt;
 };

 static inline u32 sp_readl(void __iomem *addr, unsigned int offset)
 {
 	return readl(addr + offset);
 }

 static inline void sp_writel(void __iomem *addr, unsigned int offset, u32 data)
 {
 	writel(data, addr + offset);
 }

 /**
  * k3_sec_proxy_of_xlate() - Translation of phandle to channel
  * @chan:	Mailbox channel
  * @args:	Phandle Pointer
  *
  * Translates the phandle args and fills up the Mailbox channel from client.
  * Return: 0 if all goes good, else return corresponding error message.
  */
 static int k3_sec_proxy_of_xlate(struct mbox_chan *chan,
 				 struct ofnode_phandle_args *args)
 {
 	struct k3_sec_proxy_mbox *spm = dev_get_priv(chan->dev);
 	int ind, i;

 	debug("%s(chan=%p)\n", __func__, chan);

 	if (args->args_count != 1) {
 		debug("Invaild args_count: %d\n", args->args_count);
 		return -EINVAL;
 	}
 	ind = args->args[0];

 	for (i = 0; i < spm->desc->num_valid_threads; i++)
 		if (spm->chans[i].id == ind) {
 			chan->id = ind;
 			chan->con_priv = &spm->chans[i];
 			return 0;
 		}

 	dev_err(chan->dev, "%s: Invalid Thread ID %d\n", __func__, ind);
 	return -ENOENT;
 }

 /**
  * k3_sec_proxy_request() - Request for mailbox channel
  * @chan:	Channel Pointer
  */
 static int k3_sec_proxy_request(struct mbox_chan *chan)
 {
 	debug("%s(chan=%p)\n", __func__, chan);

 	return 0;
 }

 /**
  * k3_sec_proxy_free() - Free the mailbox channel
  * @chan:	Channel Pointer
  */
 static int k3_sec_proxy_free(struct mbox_chan *chan)
 {
 	debug("%s(chan=%p)\n", __func__, chan);

 	return 0;
 }

 /**
  * k3_sec_proxy_verify_thread() - Verify thread status before
  *				  sending/receiving data.
  * @spt:	pointer to secure proxy thread description
  * @dir:	Direction of the thread
  *
  * Return: 0 if all goes good, else appropriate error message.
  */
 static inline int k3_sec_proxy_verify_thread(struct k3_sec_proxy_thread *spt,
 					     u8 dir)
 {
 	/* Check for any errors already available */
 	if (sp_readl(spt->rt, RT_THREAD_STATUS) &
 	    RT_THREAD_STATUS_ERROR_MASK) {
 		printf("%s: Thread %d is corrupted, cannot send data.\n",
 		       __func__, spt->id);
 		return -EINVAL;
 	}

 	/* Make sure thread is configured for right direction */
 	if ((sp_readl(spt->scfg, SCFG_THREAD_CTRL)
 	    & SCFG_THREAD_CTRL_DIR_MASK) >> SCFG_THREAD_CTRL_DIR_SHIFT != dir) {
 		if (dir)
 			printf("%s: Trying to receive data on tx Thread %d\n",
 			       __func__, spt->id);
 		else
 			printf("%s: Trying to send data on rx Thread %d\n",
 			       __func__, spt->id);
 		return -EINVAL;
 	}

 	/* Check the message queue before sending/receiving data */
 	if (!(sp_readl(spt->rt, RT_THREAD_STATUS) &
 	      RT_THREAD_STATUS_CUR_CNT_MASK))
 		return -ENODATA;

 	return 0;
 }

 /**
  * k3_sec_proxy_send() - Send data via mailbox channel
  * @chan:	Channel Pointer
  * @data:	Pointer to k3_sec_proxy_msg
  *
  * Return: 0 if all goes good, else appropriate error message.
  */
 static int k3_sec_proxy_send(struct mbox_chan *chan, const void *data)
 {
 	const struct k3_sec_proxy_msg *msg = (struct k3_sec_proxy_msg *)data;
 	struct k3_sec_proxy_mbox *spm = dev_get_priv(chan->dev);
 	struct k3_sec_proxy_thread *spt = chan->con_priv;
 	int num_words, trail_bytes, ret;
 	void __iomem *data_reg;
 	u32 *word_data;

 	debug("%s(chan=%p, data=%p)\n", __func__, chan, data);

 	ret = k3_sec_proxy_verify_thread(spt, THREAD_IS_TX);
 	if (ret) {
 		dev_err(chan->dev,
 			"%s: Thread%d verification failed. ret = %d\n",
 			__func__, spt->id, ret);
 		return ret;
 	}

 	/* Check the message size. */
 	if (msg->len > spm->desc->max_msg_size) {
 		dev_err(chan->dev,
 			"%s: Thread %ld message length %zu > max msg size %d\n",
 		       __func__, chan->id, msg->len, spm->desc->max_msg_size);
 		return -EINVAL;
 	}

 	/* Send the message */
 	data_reg = spt->data + spm->desc->data_start_offset;
 	for (num_words = msg->len / sizeof(u32), word_data = (u32 *)msg->buf;
 	     num_words;
 	     num_words--, data_reg += sizeof(u32), word_data++)
 		writel(*word_data, data_reg);

 	trail_bytes = msg->len % sizeof(u32);
 	if (trail_bytes) {
 		u32 data_trail = *word_data;

 		/* Ensure all unused data is 0 */
 		data_trail &= 0xFFFFFFFF >> (8 * (sizeof(u32) - trail_bytes));
 		writel(data_trail, data_reg);
 		data_reg++;
 	}

 	/*
 	 * 'data_reg' indicates next register to write. If we did not already
 	 * write on tx complete reg(last reg), we must do so for transmit
 	 */
 	if (data_reg <= (spt->data + spm->desc->data_end_offset))
 		sp_writel(spt->data, spm->desc->data_end_offset, 0);

 	debug("%s: Message successfully sent on thread %ld\n",
 	      __func__, chan->id);

 	return 0;
 }

 /**
  * k3_sec_proxy_recv() - Receive data via mailbox channel
  * @chan:	Channel Pointer
  * @data:	Pointer to k3_sec_proxy_msg
  *
  * Return: 0 if all goes good, else appropriate error message.
  */
 static int k3_sec_proxy_recv(struct mbox_chan *chan, void *data)
 {
 	struct k3_sec_proxy_mbox *spm = dev_get_priv(chan->dev);
 	struct k3_sec_proxy_thread *spt = chan->con_priv;
 	struct k3_sec_proxy_msg *msg = data;
 	void __iomem *data_reg;
 	int num_words, ret;
 	u32 *word_data;

 	debug("%s(chan=%p, data=%p)\n", __func__, chan, data);

 	ret = k3_sec_proxy_verify_thread(spt, THREAD_IS_RX);
 	if (ret)
 		return ret;

 	msg->len = spm->desc->max_msg_size;
 	msg->buf = spt->rx_buf;
 	data_reg = spt->data + spm->desc->data_start_offset;
 	word_data = spt->rx_buf;
 	for (num_words = spm->desc->max_msg_size / sizeof(u32);
 	     num_words;
 	     num_words--, data_reg += sizeof(u32), word_data++)
 		*word_data = readl(data_reg);

 	debug("%s: Message successfully received from thread %ld\n",
 	      __func__, chan->id);

 	return 0;
 }

 struct mbox_ops k3_sec_proxy_mbox_ops = {
 	.of_xlate = k3_sec_proxy_of_xlate,
 	.request = k3_sec_proxy_request,
 	.rfree = k3_sec_proxy_free,
 	.send = k3_sec_proxy_send,
 	.recv = k3_sec_proxy_recv,
 };

 /**
  * k3_sec_proxy_of_to_priv() - generate private data from device tree
  * @dev:	corresponding k3 secure proxy device
  * @spm:	pointer to driver specific private data
  *
  * Return: 0 if all went ok, else corresponding error message.
  */
 static int k3_sec_proxy_of_to_priv(struct udevice *dev,
 				   struct k3_sec_proxy_mbox *spm)
 {
 	const void *blob = gd->fdt_blob;

 	if (!blob) {
 		debug("'%s' no dt?\n", dev->name);
 		return -ENODEV;
 	}

 	spm->target_data = devfdt_get_addr_name(dev, "target_data");
 	if (spm->target_data == FDT_ADDR_T_NONE) {
 		dev_err(dev, "No reg property for target data base\n");
 		return -EINVAL;
 	}

 	spm->scfg = devfdt_get_addr_name(dev, "scfg");
 	if (spm->rt == FDT_ADDR_T_NONE) {
 		dev_err(dev, "No reg property for Secure Cfg base\n");
 		return -EINVAL;
 	}

 	spm->rt = devfdt_get_addr_name(dev, "rt");
 	if (spm->rt == FDT_ADDR_T_NONE) {
 		dev_err(dev, "No reg property for Real Time Cfg base\n");
 		return -EINVAL;
 	}

 	return 0;
 }

 /**
  * k3_sec_proxy_thread_setup - Initialize the parameters for all valid threads
  * @spm:	Mailbox instance for which threads needs to be initialized
  *
  * Return: 0 if all went ok, else corresponding error message
  */
 static int k3_sec_proxy_thread_setup(struct k3_sec_proxy_mbox *spm)
 {
 	struct k3_sec_proxy_thread *spt;
 	int i, ind;

 	for (i = 0; i < spm->desc->num_valid_threads; i++) {
 		spt = &spm->chans[i];
 		ind = spm->desc->valid_threads[i];
 		spt->id = ind;
 		spt->data = (void *)SEC_PROXY_THREAD(spm->target_data, ind);
 		spt->scfg = (void *)SEC_PROXY_THREAD(spm->scfg, ind);
 		spt->rt = (void *)SEC_PROXY_THREAD(spm->rt, ind);
 		spt->rx_buf = calloc(1, spm->desc->max_msg_size);
 		if (!spt->rx_buf)
 			return -ENOMEM;
 	}

 	return 0;
 }

 /**
  * k3_sec_proxy_probe() - Basic probe
  * @dev:	corresponding mailbox device
  *
  * Return: 0 if all went ok, else corresponding error message
  */
 static int k3_sec_proxy_probe(struct udevice *dev)
 {
 	struct k3_sec_proxy_mbox *spm = dev_get_priv(dev);
 	int ret;

 	debug("%s(dev=%p)\n", __func__, dev);

 	ret = k3_sec_proxy_of_to_priv(dev, spm);
 	if (ret)
 		return ret;

 	spm->desc = (void *)dev_get_driver_data(dev);
 	spm->chans = calloc(spm->desc->num_valid_threads,
 			    sizeof(struct k3_sec_proxy_thread));
 	if (!spm->chans)
 		return -ENOMEM;

 	ret = k3_sec_proxy_thread_setup(spm);
 	if (ret) {
 		debug("%s: secure proxy thread setup failed\n", __func__);
 		return ret;
 	}

 	return 0;
 }

 static int k3_sec_proxy_remove(struct udevice *dev)
 {
 	struct k3_sec_proxy_mbox *spm = dev_get_priv(dev);

 	debug("%s(dev=%p)\n", __func__, dev);

 	free(spm->chans);

 	return 0;
 }

 /*
  * Thread ID #4: ROM request
  * Thread ID #5: ROM response, SYSFW notify
  * Thread ID #6: SYSFW request response
  * Thread ID #7: SYSFW request high priority
  * Thread ID #8: SYSFW request low priority
  * Thread ID #9: SYSFW notify response
  */
 static const u32 am6x_valid_threads[] = { 4, 5, 6, 7, 8, 9, 11, 13 };

 static const struct k3_sec_proxy_desc am654_desc = {
 	.thread_count = 90,
 	.max_msg_size = 60,
 	.data_start_offset = 0x4,
 	.data_end_offset = 0x3C,
 	.valid_threads = am6x_valid_threads,
 	.num_valid_threads = ARRAY_SIZE(am6x_valid_threads),
 };

 static const struct udevice_id k3_sec_proxy_ids[] = {
 	{ .compatible = "ti,am654-secure-proxy", .data = (ulong)&am654_desc},
 	{ }
 };

 U_BOOT_DRIVER(k3_sec_proxy) = {
 	.name = "k3-secure-proxy",
 	.id = UCLASS_MAILBOX,
 	.of_match = k3_sec_proxy_ids,
 	.probe = k3_sec_proxy_probe,
 	.remove = k3_sec_proxy_remove,
 	.priv_auto	= sizeof(struct k3_sec_proxy_mbox),
 	.ops = &k3_sec_proxy_mbox_ops,
 };
	// SPDX-License-Identifier: GPL-2.0+
	/*
	* Texas Instruments' K3 Secure proxy Driver
	*
	* Copyright (C) 2017-2018 Texas Instruments Incorporated - http://www.ti.com/
	* Lokesh Vutla <lokeshvutla@ti.com>
	*/

	#include <common.h>
	#include <log.h>
	#include <malloc.h>
	#include <asm/io.h>
	#include <dm/device_compat.h>
	#include <linux/types.h>
	#include <linux/bitops.h>
	#include <linux/soc/ti/k3-sec-proxy.h>
	#include <dm.h>
	#include <mailbox-uclass.h>

	DECLARE_GLOBAL_DATA_PTR;

	/* SEC PROXY RT THREAD STATUS */
	#define RT_THREAD_STATUS 0x0
	#define RT_THREAD_THRESHOLD 0x4
	#define RT_THREAD_STATUS_ERROR_SHIFT 31
	#define RT_THREAD_STATUS_ERROR_MASK BIT(31)
	#define RT_THREAD_STATUS_CUR_CNT_SHIFT 0
	#define RT_THREAD_STATUS_CUR_CNT_MASK GENMASK(7, 0)

	/* SEC PROXY SCFG THREAD CTRL */
	#define SCFG_THREAD_CTRL 0x1000
	#define SCFG_THREAD_CTRL_DIR_SHIFT 31
	#define SCFG_THREAD_CTRL_DIR_MASK BIT(31)

	#define SEC_PROXY_THREAD(base, x) ((base) + (0x1000 * (x)))
	#define THREAD_IS_RX 1
	#define THREAD_IS_TX 0

	/**
	* struct k3_sec_proxy_desc - Description of secure proxy integration.
	* @thread_count: Number of Threads.
	* @max_msg_size: Message size in bytes.
	* @data_start_offset: Offset of the First data register of the thread
	* @data_end_offset: Offset of the Last data register of the thread
	* @valid_threads: List of Valid threads that the processor can access
	* @num_valid_threads: Number of valid threads.
	*/
	struct k3_sec_proxy_desc {
	u16 thread_count;
	u16 max_msg_size;
	u16 data_start_offset;
	u16 data_end_offset;
	const u32 *valid_threads;
	u32 num_valid_threads;
	};

	/**
	* struct k3_sec_proxy_thread - Description of a secure proxy Thread
	* @id: Thread ID
	* @data: Thread Data path region for target
	* @scfg: Secure Config Region for Thread
	* @rt: RealTime Region for Thread
	* @rx_buf: Receive buffer data, max message size.
	*/
	struct k3_sec_proxy_thread {
	u32 id;
	void __iomem *data;
	void __iomem *scfg;
	void __iomem *rt;
	u32 *rx_buf;
	};

	/**
	* struct k3_sec_proxy_mbox - Description of a Secure Proxy Instance
	* @chan: Mailbox Channel
	* @desc: Description of the SoC integration
	* @chans: Array for valid thread instances
	* @target_data: Secure Proxy region for Target Data
	* @scfg: Secure Proxy Region for Secure configuration.
	* @rt: Secure proxy Region for Real Time Region.
	*/
	struct k3_sec_proxy_mbox {
	struct mbox_chan chan;
	struct k3_sec_proxy_desc *desc;
	struct k3_sec_proxy_thread *chans;
	phys_addr_t target_data;
	phys_addr_t scfg;
	phys_addr_t rt;
	};

	static inline u32 sp_readl(void __iomem *addr, unsigned int offset)
	{
	return readl(addr + offset);
	}

	static inline void sp_writel(void __iomem *addr, unsigned int offset, u32 data)
	{
	writel(data, addr + offset);
	}

	/**
	* k3_sec_proxy_of_xlate() - Translation of phandle to channel
	* @chan: Mailbox channel
	* @args: Phandle Pointer
	*
	* Translates the phandle args and fills up the Mailbox channel from client.
	* Return: 0 if all goes good, else return corresponding error message.
	*/
	static int k3_sec_proxy_of_xlate(struct mbox_chan *chan,
	struct ofnode_phandle_args *args)
	{
	struct k3_sec_proxy_mbox *spm = dev_get_priv(chan->dev);
	int ind, i;

	debug("%s(chan=%p)\n", __func__, chan);

	if (args->args_count != 1) {
	debug("Invaild args_count: %d\n", args->args_count);
	return -EINVAL;
	}
	ind = args->args[0];

	for (i = 0; i < spm->desc->num_valid_threads; i++)
	if (spm->chans[i].id == ind) {
	chan->id = ind;
	chan->con_priv = &spm->chans[i];
	return 0;
	}

	dev_err(chan->dev, "%s: Invalid Thread ID %d\n", __func__, ind);
	return -ENOENT;
	}

	/**
	* k3_sec_proxy_request() - Request for mailbox channel
	* @chan: Channel Pointer
	*/
	static int k3_sec_proxy_request(struct mbox_chan *chan)
	{
	debug("%s(chan=%p)\n", __func__, chan);

	return 0;
	}

	/**
	* k3_sec_proxy_free() - Free the mailbox channel
	* @chan: Channel Pointer
	*/
	static int k3_sec_proxy_free(struct mbox_chan *chan)
	{
	debug("%s(chan=%p)\n", __func__, chan);

	return 0;
	}

	/**
	* k3_sec_proxy_verify_thread() - Verify thread status before
	* sending/receiving data.
	* @spt: pointer to secure proxy thread description
	* @dir: Direction of the thread
	*
	* Return: 0 if all goes good, else appropriate error message.
	*/
	static inline int k3_sec_proxy_verify_thread(struct k3_sec_proxy_thread *spt,
	u8 dir)
	{
	/* Check for any errors already available */
	if (sp_readl(spt->rt, RT_THREAD_STATUS) &
	RT_THREAD_STATUS_ERROR_MASK) {
	printf("%s: Thread %d is corrupted, cannot send data.\n",
	__func__, spt->id);
	return -EINVAL;
	}

	/* Make sure thread is configured for right direction */
	if ((sp_readl(spt->scfg, SCFG_THREAD_CTRL)
	& SCFG_THREAD_CTRL_DIR_MASK) >> SCFG_THREAD_CTRL_DIR_SHIFT != dir) {
	if (dir)
	printf("%s: Trying to receive data on tx Thread %d\n",
	__func__, spt->id);
	else
	printf("%s: Trying to send data on rx Thread %d\n",
	__func__, spt->id);
	return -EINVAL;
	}

	/* Check the message queue before sending/receiving data */
	if (!(sp_readl(spt->rt, RT_THREAD_STATUS) &
	RT_THREAD_STATUS_CUR_CNT_MASK))
	return -ENODATA;

	return 0;
	}

	/**
	* k3_sec_proxy_send() - Send data via mailbox channel
	* @chan: Channel Pointer
	* @data: Pointer to k3_sec_proxy_msg
	*
	* Return: 0 if all goes good, else appropriate error message.
	*/
	static int k3_sec_proxy_send(struct mbox_chan chan, const void data)
	{
	const struct k3_sec_proxy_msg msg = (struct k3_sec_proxy_msg )data;
	struct k3_sec_proxy_mbox *spm = dev_get_priv(chan->dev);
	struct k3_sec_proxy_thread *spt = chan->con_priv;
	int num_words, trail_bytes, ret;
	void __iomem *data_reg;
	u32 *word_data;

	debug("%s(chan=%p, data=%p)\n", __func__, chan, data);

	ret = k3_sec_proxy_verify_thread(spt, THREAD_IS_TX);
	if (ret) {
	dev_err(chan->dev,
	"%s: Thread%d verification failed. ret = %d\n",
	__func__, spt->id, ret);
	return ret;
	}

	/* Check the message size. */
	if (msg->len > spm->desc->max_msg_size) {
	dev_err(chan->dev,
	"%s: Thread %ld message length %zu > max msg size %d\n",
	__func__, chan->id, msg->len, spm->desc->max_msg_size);
	return -EINVAL;
	}

	/* Send the message */
	data_reg = spt->data + spm->desc->data_start_offset;
	for (num_words = msg->len / sizeof(u32), word_data = (u32 *)msg->buf;
	num_words;
	num_words--, data_reg += sizeof(u32), word_data++)
	writel(*word_data, data_reg);

	trail_bytes = msg->len % sizeof(u32);
	if (trail_bytes) {
	u32 data_trail = *word_data;

	/* Ensure all unused data is 0 */
	data_trail &= 0xFFFFFFFF >> (8 * (sizeof(u32) - trail_bytes));
	writel(data_trail, data_reg);
	data_reg++;
	}

	/*
	* 'data_reg' indicates next register to write. If we did not already
	* write on tx complete reg(last reg), we must do so for transmit
	*/
	if (data_reg <= (spt->data + spm->desc->data_end_offset))
	sp_writel(spt->data, spm->desc->data_end_offset, 0);

	debug("%s: Message successfully sent on thread %ld\n",
	__func__, chan->id);

	return 0;
	}

	/**
	* k3_sec_proxy_recv() - Receive data via mailbox channel
	* @chan: Channel Pointer
	* @data: Pointer to k3_sec_proxy_msg
	*
	* Return: 0 if all goes good, else appropriate error message.
	*/
	static int k3_sec_proxy_recv(struct mbox_chan chan, void data)
	{
	struct k3_sec_proxy_mbox *spm = dev_get_priv(chan->dev);
	struct k3_sec_proxy_thread *spt = chan->con_priv;
	struct k3_sec_proxy_msg *msg = data;
	void __iomem *data_reg;
	int num_words, ret;
	u32 *word_data;

	debug("%s(chan=%p, data=%p)\n", __func__, chan, data);

	ret = k3_sec_proxy_verify_thread(spt, THREAD_IS_RX);
	if (ret)
	return ret;

	msg->len = spm->desc->max_msg_size;
	msg->buf = spt->rx_buf;
	data_reg = spt->data + spm->desc->data_start_offset;
	word_data = spt->rx_buf;
	for (num_words = spm->desc->max_msg_size / sizeof(u32);
	num_words;
	num_words--, data_reg += sizeof(u32), word_data++)
	*word_data = readl(data_reg);

	debug("%s: Message successfully received from thread %ld\n",
	__func__, chan->id);

	return 0;
	}

	struct mbox_ops k3_sec_proxy_mbox_ops = {
	.of_xlate = k3_sec_proxy_of_xlate,
	.request = k3_sec_proxy_request,
	.rfree = k3_sec_proxy_free,
	.send = k3_sec_proxy_send,
	.recv = k3_sec_proxy_recv,
	};

	/**
	* k3_sec_proxy_of_to_priv() - generate private data from device tree
	* @dev: corresponding k3 secure proxy device
	* @spm: pointer to driver specific private data
	*
	* Return: 0 if all went ok, else corresponding error message.
	*/
	static int k3_sec_proxy_of_to_priv(struct udevice *dev,
	struct k3_sec_proxy_mbox *spm)
	{
	const void *blob = gd->fdt_blob;

	if (!blob) {
	debug("'%s' no dt?\n", dev->name);
	return -ENODEV;
	}

	spm->target_data = devfdt_get_addr_name(dev, "target_data");
	if (spm->target_data == FDT_ADDR_T_NONE) {
	dev_err(dev, "No reg property for target data base\n");
	return -EINVAL;
	}

	spm->scfg = devfdt_get_addr_name(dev, "scfg");
	if (spm->rt == FDT_ADDR_T_NONE) {
	dev_err(dev, "No reg property for Secure Cfg base\n");
	return -EINVAL;
	}

	spm->rt = devfdt_get_addr_name(dev, "rt");
	if (spm->rt == FDT_ADDR_T_NONE) {
	dev_err(dev, "No reg property for Real Time Cfg base\n");
	return -EINVAL;
	}

	return 0;
	}

	/**
	* k3_sec_proxy_thread_setup - Initialize the parameters for all valid threads
	* @spm: Mailbox instance for which threads needs to be initialized
	*
	* Return: 0 if all went ok, else corresponding error message
	*/
	static int k3_sec_proxy_thread_setup(struct k3_sec_proxy_mbox *spm)
	{
	struct k3_sec_proxy_thread *spt;
	int i, ind;

	for (i = 0; i < spm->desc->num_valid_threads; i++) {
	spt = &spm->chans[i];
	ind = spm->desc->valid_threads[i];
	spt->id = ind;
	spt->data = (void *)SEC_PROXY_THREAD(spm->target_data, ind);
	spt->scfg = (void *)SEC_PROXY_THREAD(spm->scfg, ind);
	spt->rt = (void *)SEC_PROXY_THREAD(spm->rt, ind);
	spt->rx_buf = calloc(1, spm->desc->max_msg_size);
	if (!spt->rx_buf)
	return -ENOMEM;
	}

	return 0;
	}

	/**
	* k3_sec_proxy_probe() - Basic probe
	* @dev: corresponding mailbox device
	*
	* Return: 0 if all went ok, else corresponding error message
	*/
	static int k3_sec_proxy_probe(struct udevice *dev)
	{
	struct k3_sec_proxy_mbox *spm = dev_get_priv(dev);
	int ret;

	debug("%s(dev=%p)\n", __func__, dev);

	ret = k3_sec_proxy_of_to_priv(dev, spm);
	if (ret)
	return ret;

	spm->desc = (void *)dev_get_driver_data(dev);
	spm->chans = calloc(spm->desc->num_valid_threads,
	sizeof(struct k3_sec_proxy_thread));
	if (!spm->chans)
	return -ENOMEM;

	ret = k3_sec_proxy_thread_setup(spm);
	if (ret) {
	debug("%s: secure proxy thread setup failed\n", __func__);
	return ret;
	}

	return 0;
	}

	static int k3_sec_proxy_remove(struct udevice *dev)
	{
	struct k3_sec_proxy_mbox *spm = dev_get_priv(dev);

	debug("%s(dev=%p)\n", __func__, dev);

	free(spm->chans);

	return 0;
	}

	/*
	* Thread ID #4: ROM request
	* Thread ID #5: ROM response, SYSFW notify
	* Thread ID #6: SYSFW request response
	* Thread ID #7: SYSFW request high priority
	* Thread ID #8: SYSFW request low priority
	* Thread ID #9: SYSFW notify response
	*/
	static const u32 am6x_valid_threads[] = { 4, 5, 6, 7, 8, 9, 11, 13 };

	static const struct k3_sec_proxy_desc am654_desc = {
	.thread_count = 90,
	.max_msg_size = 60,
	.data_start_offset = 0x4,
	.data_end_offset = 0x3C,
	.valid_threads = am6x_valid_threads,
	.num_valid_threads = ARRAY_SIZE(am6x_valid_threads),
	};

	static const struct udevice_id k3_sec_proxy_ids[] = {
	{ .compatible = "ti,am654-secure-proxy", .data = (ulong)&am654_desc},
	{ }
	};

	U_BOOT_DRIVER(k3_sec_proxy) = {
	.name = "k3-secure-proxy",
	.id = UCLASS_MAILBOX,
	.of_match = k3_sec_proxy_ids,
	.probe = k3_sec_proxy_probe,
	.remove = k3_sec_proxy_remove,
	.priv_auto = sizeof(struct k3_sec_proxy_mbox),
	.ops = &k3_sec_proxy_mbox_ops,
	};