drivers/fpga/stratix10-soc.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0
 /*
  * FPGA Manager Driver for Intel Stratix10 SoC
  *
  *  Copyright (C) 2018 Intel Corporation
  */
 #include <linux/completion.h>
 #include <linux/fpga/fpga-mgr.h>
 #include <linux/firmware/intel/stratix10-svc-client.h>
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/of_platform.h>

 /*
  * FPGA programming requires a higher level of privilege (EL3), per the SoC
  * design.
  */
 #define NUM_SVC_BUFS	4
 #define SVC_BUF_SIZE	SZ_512K

 /* Indicates buffer is in use if set */
 #define SVC_BUF_LOCK	0

 #define S10_BUFFER_TIMEOUT (msecs_to_jiffies(SVC_RECONFIG_BUFFER_TIMEOUT_MS))
 #define S10_RECONFIG_TIMEOUT (msecs_to_jiffies(SVC_RECONFIG_REQUEST_TIMEOUT_MS))

 /*
  * struct s10_svc_buf
  * buf:  virtual address of buf provided by service layer
  * lock: locked if buffer is in use
  */
 struct s10_svc_buf {
 	char *buf;
 	unsigned long lock;
 };

 struct s10_priv {
 	struct stratix10_svc_chan *chan;
 	struct stratix10_svc_client client;
 	struct completion status_return_completion;
 	struct s10_svc_buf svc_bufs[NUM_SVC_BUFS];
 	unsigned long status;
 };

 static int s10_svc_send_msg(struct s10_priv *priv,
 			    enum stratix10_svc_command_code command,
 			    void *payload, u32 payload_length)
 {
 	struct stratix10_svc_chan *chan = priv->chan;
 	struct device *dev = priv->client.dev;
 	struct stratix10_svc_client_msg msg;
 	int ret;

 	dev_dbg(dev, "%s cmd=%d payload=%p length=%d\n",
 		__func__, command, payload, payload_length);

 	msg.command = command;
 	msg.payload = payload;
 	msg.payload_length = payload_length;

 	ret = stratix10_svc_send(chan, &msg);
 	dev_dbg(dev, "stratix10_svc_send returned status %d\n", ret);

 	return ret;
 }

 /*
  * Free buffers allocated from the service layer's pool that are not in use.
  * Return true when all buffers are freed.
  */
 static bool s10_free_buffers(struct fpga_manager *mgr)
 {
 	struct s10_priv *priv = mgr->priv;
 	uint num_free = 0;
 	uint i;

 	for (i = 0; i < NUM_SVC_BUFS; i++) {
 		if (!priv->svc_bufs[i].buf) {
 			num_free++;
 			continue;
 		}

 		if (!test_and_set_bit_lock(SVC_BUF_LOCK,
 					   &priv->svc_bufs[i].lock)) {
 			stratix10_svc_free_memory(priv->chan,
 						  priv->svc_bufs[i].buf);
 			priv->svc_bufs[i].buf = NULL;
 			num_free++;
 		}
 	}

 	return num_free == NUM_SVC_BUFS;
 }

 /*
  * Returns count of how many buffers are not in use.
  */
 static uint s10_free_buffer_count(struct fpga_manager *mgr)
 {
 	struct s10_priv *priv = mgr->priv;
 	uint num_free = 0;
 	uint i;

 	for (i = 0; i < NUM_SVC_BUFS; i++)
 		if (!priv->svc_bufs[i].buf)
 			num_free++;

 	return num_free;
 }

 /*
  * s10_unlock_bufs
  * Given the returned buffer address, match that address to our buffer struct
  * and unlock that buffer.  This marks it as available to be refilled and sent
  * (or freed).
  * priv: private data
  * kaddr: kernel address of buffer that was returned from service layer
  */
 static void s10_unlock_bufs(struct s10_priv *priv, void *kaddr)
 {
 	uint i;

 	if (!kaddr)
 		return;

 	for (i = 0; i < NUM_SVC_BUFS; i++)
 		if (priv->svc_bufs[i].buf == kaddr) {
 			clear_bit_unlock(SVC_BUF_LOCK,
 					 &priv->svc_bufs[i].lock);
 			return;
 		}

 	WARN(1, "Unknown buffer returned from service layer %p\n", kaddr);
 }

 /*
  * s10_receive_callback - callback for service layer to use to provide client
  * (this driver) messages received through the mailbox.
  * client: service layer client struct
  * data: message from service layer
  */
 static void s10_receive_callback(struct stratix10_svc_client *client,
 				 struct stratix10_svc_cb_data *data)
 {
 	struct s10_priv *priv = client->priv;
 	u32 status;
 	int i;

 	WARN_ONCE(!data, "%s: stratix10_svc_rc_data = NULL", __func__);

 	status = data->status;

 	/*
 	 * Here we set status bits as we receive them.  Elsewhere, we always use
 	 * test_and_clear_bit() to check status in priv->status
 	 */
 	for (i = 0; i <= SVC_STATUS_RECONFIG_ERROR; i++)
 		if (status & (1 << i))
 			set_bit(i, &priv->status);

 	if (status & BIT(SVC_STATUS_RECONFIG_BUFFER_DONE)) {
 		s10_unlock_bufs(priv, data->kaddr1);
 		s10_unlock_bufs(priv, data->kaddr2);
 		s10_unlock_bufs(priv, data->kaddr3);
 	}

 	complete(&priv->status_return_completion);
 }

 /*
  * s10_ops_write_init - prepare for FPGA reconfiguration by requesting
  * partial reconfig and allocating buffers from the service layer.
  */
 static int s10_ops_write_init(struct fpga_manager *mgr,
 			      struct fpga_image_info *info,
 			      const char *buf, size_t count)
 {
 	struct s10_priv *priv = mgr->priv;
 	struct device *dev = priv->client.dev;
 	struct stratix10_svc_command_config_type ctype;
 	char *kbuf;
 	uint i;
 	int ret;

 	ctype.flags = 0;
 	if (info->flags & FPGA_MGR_PARTIAL_RECONFIG) {
 		dev_dbg(dev, "Requesting partial reconfiguration.\n");
 		ctype.flags |= BIT(COMMAND_RECONFIG_FLAG_PARTIAL);
 	} else {
 		dev_dbg(dev, "Requesting full reconfiguration.\n");
 	}

 	reinit_completion(&priv->status_return_completion);
 	ret = s10_svc_send_msg(priv, COMMAND_RECONFIG,
 			       &ctype, sizeof(ctype));
 	if (ret < 0)
 		goto init_done;

 	ret = wait_for_completion_interruptible_timeout(
 		&priv->status_return_completion, S10_RECONFIG_TIMEOUT);
 	if (!ret) {
 		dev_err(dev, "timeout waiting for RECONFIG_REQUEST\n");
 		ret = -ETIMEDOUT;
 		goto init_done;
 	}
 	if (ret < 0) {
 		dev_err(dev, "error (%d) waiting for RECONFIG_REQUEST\n", ret);
 		goto init_done;
 	}

 	ret = 0;
 	if (!test_and_clear_bit(SVC_STATUS_RECONFIG_REQUEST_OK,
 				&priv->status)) {
 		ret = -ETIMEDOUT;
 		goto init_done;
 	}

 	/* Allocate buffers from the service layer's pool. */
 	for (i = 0; i < NUM_SVC_BUFS; i++) {
 		kbuf = stratix10_svc_allocate_memory(priv->chan, SVC_BUF_SIZE);
 		if (!kbuf) {
 			s10_free_buffers(mgr);
 			ret = -ENOMEM;
 			goto init_done;
 		}

 		priv->svc_bufs[i].buf = kbuf;
 		priv->svc_bufs[i].lock = 0;
 	}

 init_done:
 	stratix10_svc_done(priv->chan);
 	return ret;
 }

 /*
  * s10_send_buf - send a buffer to the service layer queue
  * mgr: fpga manager struct
  * buf: fpga image buffer
  * count: size of buf in bytes
  * Returns # of bytes transferred or -ENOBUFS if the all the buffers are in use
  * or if the service queue is full. Never returns 0.
  */
 static int s10_send_buf(struct fpga_manager *mgr, const char *buf, size_t count)
 {
 	struct s10_priv *priv = mgr->priv;
 	struct device *dev = priv->client.dev;
 	void *svc_buf;
 	size_t xfer_sz;
 	int ret;
 	uint i;

 	/* get/lock a buffer that that's not being used */
 	for (i = 0; i < NUM_SVC_BUFS; i++)
 		if (!test_and_set_bit_lock(SVC_BUF_LOCK,
 					   &priv->svc_bufs[i].lock))
 			break;

 	if (i == NUM_SVC_BUFS)
 		return -ENOBUFS;

 	xfer_sz = count < SVC_BUF_SIZE ? count : SVC_BUF_SIZE;

 	svc_buf = priv->svc_bufs[i].buf;
 	memcpy(svc_buf, buf, xfer_sz);
 	ret = s10_svc_send_msg(priv, COMMAND_RECONFIG_DATA_SUBMIT,
 			       svc_buf, xfer_sz);
 	if (ret < 0) {
 		dev_err(dev,
 			"Error while sending data to service layer (%d)", ret);
 		clear_bit_unlock(SVC_BUF_LOCK, &priv->svc_bufs[i].lock);
 		return ret;
 	}

 	return xfer_sz;
 }

 /*
  * Send a FPGA image to privileged layers to write to the FPGA.  When done
  * sending, free all service layer buffers we allocated in write_init.
  */
 static int s10_ops_write(struct fpga_manager *mgr, const char *buf,
 			 size_t count)
 {
 	struct s10_priv *priv = mgr->priv;
 	struct device *dev = priv->client.dev;
 	long wait_status;
 	int sent = 0;
 	int ret = 0;

 	/*
 	 * Loop waiting for buffers to be returned.  When a buffer is returned,
 	 * reuse it to send more data or free if if all data has been sent.
 	 */
 	while (count > 0 || s10_free_buffer_count(mgr) != NUM_SVC_BUFS) {
 		reinit_completion(&priv->status_return_completion);

 		if (count > 0) {
 			sent = s10_send_buf(mgr, buf, count);
 			if (sent < 0)
 				continue;

 			count -= sent;
 			buf += sent;
 		} else {
 			if (s10_free_buffers(mgr))
 				return 0;

 			ret = s10_svc_send_msg(
 				priv, COMMAND_RECONFIG_DATA_CLAIM,
 				NULL, 0);
 			if (ret < 0)
 				break;
 		}

 		/*
 		 * If callback hasn't already happened, wait for buffers to be
 		 * returned from service layer
 		 */
 		wait_status = 1; /* not timed out */
 		if (!priv->status)
 			wait_status = wait_for_completion_interruptible_timeout(
 				&priv->status_return_completion,
 				S10_BUFFER_TIMEOUT);

 		if (test_and_clear_bit(SVC_STATUS_RECONFIG_BUFFER_DONE,
 				       &priv->status) ||
 		    test_and_clear_bit(SVC_STATUS_RECONFIG_BUFFER_SUBMITTED,
 				       &priv->status)) {
 			ret = 0;
 			continue;
 		}

 		if (test_and_clear_bit(SVC_STATUS_RECONFIG_ERROR,
 				       &priv->status)) {
 			dev_err(dev, "ERROR - giving up - SVC_STATUS_RECONFIG_ERROR\n");
 			ret = -EFAULT;
 			break;
 		}

 		if (!wait_status) {
 			dev_err(dev, "timeout waiting for svc layer buffers\n");
 			ret = -ETIMEDOUT;
 			break;
 		}
 		if (wait_status < 0) {
 			ret = wait_status;
 			dev_err(dev,
 				"error (%d) waiting for svc layer buffers\n",
 				ret);
 			break;
 		}
 	}

 	if (!s10_free_buffers(mgr))
 		dev_err(dev, "%s not all buffers were freed\n", __func__);

 	return ret;
 }

 static int s10_ops_write_complete(struct fpga_manager *mgr,
 				  struct fpga_image_info *info)
 {
 	struct s10_priv *priv = mgr->priv;
 	struct device *dev = priv->client.dev;
 	unsigned long timeout;
 	int ret;

 	timeout = usecs_to_jiffies(info->config_complete_timeout_us);

 	do {
 		reinit_completion(&priv->status_return_completion);

 		ret = s10_svc_send_msg(priv, COMMAND_RECONFIG_STATUS, NULL, 0);
 		if (ret < 0)
 			break;

 		ret = wait_for_completion_interruptible_timeout(
 			&priv->status_return_completion, timeout);
 		if (!ret) {
 			dev_err(dev,
 				"timeout waiting for RECONFIG_COMPLETED\n");
 			ret = -ETIMEDOUT;
 			break;
 		}
 		if (ret < 0) {
 			dev_err(dev,
 				"error (%d) waiting for RECONFIG_COMPLETED\n",
 				ret);
 			break;
 		}
 		/* Not error or timeout, so ret is # of jiffies until timeout */
 		timeout = ret;
 		ret = 0;

 		if (test_and_clear_bit(SVC_STATUS_RECONFIG_COMPLETED,
 				       &priv->status))
 			break;

 		if (test_and_clear_bit(SVC_STATUS_RECONFIG_ERROR,
 				       &priv->status)) {
 			dev_err(dev, "ERROR - giving up - SVC_STATUS_RECONFIG_ERROR\n");
 			ret = -EFAULT;
 			break;
 		}
 	} while (1);

 	stratix10_svc_done(priv->chan);

 	return ret;
 }

 static enum fpga_mgr_states s10_ops_state(struct fpga_manager *mgr)
 {
 	return FPGA_MGR_STATE_UNKNOWN;
 }

 static const struct fpga_manager_ops s10_ops = {
 	.state = s10_ops_state,
 	.write_init = s10_ops_write_init,
 	.write = s10_ops_write,
 	.write_complete = s10_ops_write_complete,
 };

 static int s10_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
 	struct s10_priv *priv;
 	struct fpga_manager *mgr;
 	int ret;

 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
 	if (!priv)
 		return -ENOMEM;

 	priv->client.dev = dev;
 	priv->client.receive_cb = s10_receive_callback;
 	priv->client.priv = priv;

 	priv->chan = stratix10_svc_request_channel_byname(&priv->client,
 							  SVC_CLIENT_FPGA);
 	if (IS_ERR(priv->chan)) {
 		dev_err(dev, "couldn't get service channel (%s)\n",
 			SVC_CLIENT_FPGA);
 		return PTR_ERR(priv->chan);
 	}

 	init_completion(&priv->status_return_completion);

 	mgr = fpga_mgr_create(dev, "Stratix10 SOC FPGA Manager",
 			      &s10_ops, priv);
 	if (!mgr) {
 		dev_err(dev, "unable to create FPGA manager\n");
 		ret = -ENOMEM;
 		goto probe_err;
 	}

 	ret = fpga_mgr_register(mgr);
 	if (ret) {
 		dev_err(dev, "unable to register FPGA manager\n");
 		fpga_mgr_free(mgr);
 		goto probe_err;
 	}

 	platform_set_drvdata(pdev, mgr);
 	return ret;

 probe_err:
 	stratix10_svc_free_channel(priv->chan);
 	return ret;
 }

 static int s10_remove(struct platform_device *pdev)
 {
 	struct fpga_manager *mgr = platform_get_drvdata(pdev);
 	struct s10_priv *priv = mgr->priv;

 	fpga_mgr_unregister(mgr);
 	stratix10_svc_free_channel(priv->chan);

 	return 0;
 }

 static const struct of_device_id s10_of_match[] = {
 	{ .compatible = "intel,stratix10-soc-fpga-mgr", },
 	{},
 };

 MODULE_DEVICE_TABLE(of, s10_of_match);

 static struct platform_driver s10_driver = {
 	.probe = s10_probe,
 	.remove = s10_remove,
 	.driver = {
 		.name	= "Stratix10 SoC FPGA manager",
 		.of_match_table = of_match_ptr(s10_of_match),
 	},
 };

 static int __init s10_init(void)
 {
 	struct device_node *fw_np;
 	struct device_node *np;
 	int ret;

 	fw_np = of_find_node_by_name(NULL, "svc");
 	if (!fw_np)
 		return -ENODEV;

 	np = of_find_matching_node(fw_np, s10_of_match);
 	if (!np)
 		return -ENODEV;

 	of_node_put(np);
 	ret = of_platform_populate(fw_np, s10_of_match, NULL, NULL);
 	if (ret)
 		return ret;

 	return platform_driver_register(&s10_driver);
 }

 static void __exit s10_exit(void)
 {
 	return platform_driver_unregister(&s10_driver);
 }

 module_init(s10_init);
 module_exit(s10_exit);

 MODULE_AUTHOR("Alan Tull <atull@kernel.org>");
 MODULE_DESCRIPTION("Intel Stratix 10 SOC FPGA Manager");
 MODULE_LICENSE("GPL v2");
	// SPDX-License-Identifier: GPL-2.0
	/*
	* FPGA Manager Driver for Intel Stratix10 SoC
	*
	* Copyright (C) 2018 Intel Corporation
	*/
	#include <linux/completion.h>
	#include <linux/fpga/fpga-mgr.h>
	#include <linux/firmware/intel/stratix10-svc-client.h>
	#include <linux/module.h>
	#include <linux/of.h>
	#include <linux/of_platform.h>

	/*
	* FPGA programming requires a higher level of privilege (EL3), per the SoC
	* design.
	*/
	#define NUM_SVC_BUFS 4
	#define SVC_BUF_SIZE SZ_512K

	/* Indicates buffer is in use if set */
	#define SVC_BUF_LOCK 0

	#define S10_BUFFER_TIMEOUT (msecs_to_jiffies(SVC_RECONFIG_BUFFER_TIMEOUT_MS))
	#define S10_RECONFIG_TIMEOUT (msecs_to_jiffies(SVC_RECONFIG_REQUEST_TIMEOUT_MS))

	/*
	* struct s10_svc_buf
	* buf: virtual address of buf provided by service layer
	* lock: locked if buffer is in use
	*/
	struct s10_svc_buf {
	char *buf;
	unsigned long lock;
	};

	struct s10_priv {
	struct stratix10_svc_chan *chan;
	struct stratix10_svc_client client;
	struct completion status_return_completion;
	struct s10_svc_buf svc_bufs[NUM_SVC_BUFS];
	unsigned long status;
	};

	static int s10_svc_send_msg(struct s10_priv *priv,
	enum stratix10_svc_command_code command,
	void *payload, u32 payload_length)
	{
	struct stratix10_svc_chan *chan = priv->chan;
	struct device *dev = priv->client.dev;
	struct stratix10_svc_client_msg msg;
	int ret;

	dev_dbg(dev, "%s cmd=%d payload=%p length=%d\n",
	__func__, command, payload, payload_length);

	msg.command = command;
	msg.payload = payload;
	msg.payload_length = payload_length;

	ret = stratix10_svc_send(chan, &msg);
	dev_dbg(dev, "stratix10_svc_send returned status %d\n", ret);

	return ret;
	}

	/*
	* Free buffers allocated from the service layer's pool that are not in use.
	* Return true when all buffers are freed.
	*/
	static bool s10_free_buffers(struct fpga_manager *mgr)
	{
	struct s10_priv *priv = mgr->priv;
	uint num_free = 0;
	uint i;

	for (i = 0; i < NUM_SVC_BUFS; i++) {
	if (!priv->svc_bufs[i].buf) {
	num_free++;
	continue;
	}

	if (!test_and_set_bit_lock(SVC_BUF_LOCK,
	&priv->svc_bufs[i].lock)) {
	stratix10_svc_free_memory(priv->chan,
	priv->svc_bufs[i].buf);
	priv->svc_bufs[i].buf = NULL;
	num_free++;
	}
	}

	return num_free == NUM_SVC_BUFS;
	}

	/*
	* Returns count of how many buffers are not in use.
	*/
	static uint s10_free_buffer_count(struct fpga_manager *mgr)
	{
	struct s10_priv *priv = mgr->priv;
	uint num_free = 0;
	uint i;

	for (i = 0; i < NUM_SVC_BUFS; i++)
	if (!priv->svc_bufs[i].buf)
	num_free++;

	return num_free;
	}

	/*
	* s10_unlock_bufs
	* Given the returned buffer address, match that address to our buffer struct
	* and unlock that buffer. This marks it as available to be refilled and sent
	* (or freed).
	* priv: private data
	* kaddr: kernel address of buffer that was returned from service layer
	*/
	static void s10_unlock_bufs(struct s10_priv priv, void kaddr)
	{
	uint i;

	if (!kaddr)
	return;

	for (i = 0; i < NUM_SVC_BUFS; i++)
	if (priv->svc_bufs[i].buf == kaddr) {
	clear_bit_unlock(SVC_BUF_LOCK,
	&priv->svc_bufs[i].lock);
	return;
	}

	WARN(1, "Unknown buffer returned from service layer %p\n", kaddr);
	}

	/*
	* s10_receive_callback - callback for service layer to use to provide client
	* (this driver) messages received through the mailbox.
	* client: service layer client struct
	* data: message from service layer
	*/
	static void s10_receive_callback(struct stratix10_svc_client *client,
	struct stratix10_svc_cb_data *data)
	{
	struct s10_priv *priv = client->priv;
	u32 status;
	int i;

	WARN_ONCE(!data, "%s: stratix10_svc_rc_data = NULL", __func__);

	status = data->status;

	/*
	* Here we set status bits as we receive them. Elsewhere, we always use
	* test_and_clear_bit() to check status in priv->status
	*/
	for (i = 0; i <= SVC_STATUS_RECONFIG_ERROR; i++)
	if (status & (1 << i))
	set_bit(i, &priv->status);

	if (status & BIT(SVC_STATUS_RECONFIG_BUFFER_DONE)) {
	s10_unlock_bufs(priv, data->kaddr1);
	s10_unlock_bufs(priv, data->kaddr2);
	s10_unlock_bufs(priv, data->kaddr3);
	}

	complete(&priv->status_return_completion);
	}

	/*
	* s10_ops_write_init - prepare for FPGA reconfiguration by requesting
	* partial reconfig and allocating buffers from the service layer.
	*/
	static int s10_ops_write_init(struct fpga_manager *mgr,
	struct fpga_image_info *info,
	const char *buf, size_t count)
	{
	struct s10_priv *priv = mgr->priv;
	struct device *dev = priv->client.dev;
	struct stratix10_svc_command_config_type ctype;
	char *kbuf;
	uint i;
	int ret;

	ctype.flags = 0;
	if (info->flags & FPGA_MGR_PARTIAL_RECONFIG) {
	dev_dbg(dev, "Requesting partial reconfiguration.\n");
	ctype.flags \|= BIT(COMMAND_RECONFIG_FLAG_PARTIAL);
	} else {
	dev_dbg(dev, "Requesting full reconfiguration.\n");
	}

	reinit_completion(&priv->status_return_completion);
	ret = s10_svc_send_msg(priv, COMMAND_RECONFIG,
	&ctype, sizeof(ctype));
	if (ret < 0)
	goto init_done;

	ret = wait_for_completion_interruptible_timeout(
	&priv->status_return_completion, S10_RECONFIG_TIMEOUT);
	if (!ret) {
	dev_err(dev, "timeout waiting for RECONFIG_REQUEST\n");
	ret = -ETIMEDOUT;
	goto init_done;
	}
	if (ret < 0) {
	dev_err(dev, "error (%d) waiting for RECONFIG_REQUEST\n", ret);
	goto init_done;
	}

	ret = 0;
	if (!test_and_clear_bit(SVC_STATUS_RECONFIG_REQUEST_OK,
	&priv->status)) {
	ret = -ETIMEDOUT;
	goto init_done;
	}

	/* Allocate buffers from the service layer's pool. */
	for (i = 0; i < NUM_SVC_BUFS; i++) {
	kbuf = stratix10_svc_allocate_memory(priv->chan, SVC_BUF_SIZE);
	if (!kbuf) {
	s10_free_buffers(mgr);
	ret = -ENOMEM;
	goto init_done;
	}

	priv->svc_bufs[i].buf = kbuf;
	priv->svc_bufs[i].lock = 0;
	}

	init_done:
	stratix10_svc_done(priv->chan);
	return ret;
	}

	/*
	* s10_send_buf - send a buffer to the service layer queue
	* mgr: fpga manager struct
	* buf: fpga image buffer
	* count: size of buf in bytes
	* Returns # of bytes transferred or -ENOBUFS if the all the buffers are in use
	* or if the service queue is full. Never returns 0.
	*/
	static int s10_send_buf(struct fpga_manager mgr, const char buf, size_t count)
	{
	struct s10_priv *priv = mgr->priv;
	struct device *dev = priv->client.dev;
	void *svc_buf;
	size_t xfer_sz;
	int ret;
	uint i;

	/* get/lock a buffer that that's not being used */
	for (i = 0; i < NUM_SVC_BUFS; i++)
	if (!test_and_set_bit_lock(SVC_BUF_LOCK,
	&priv->svc_bufs[i].lock))
	break;

	if (i == NUM_SVC_BUFS)
	return -ENOBUFS;

	xfer_sz = count < SVC_BUF_SIZE ? count : SVC_BUF_SIZE;

	svc_buf = priv->svc_bufs[i].buf;
	memcpy(svc_buf, buf, xfer_sz);
	ret = s10_svc_send_msg(priv, COMMAND_RECONFIG_DATA_SUBMIT,
	svc_buf, xfer_sz);
	if (ret < 0) {
	dev_err(dev,
	"Error while sending data to service layer (%d)", ret);
	clear_bit_unlock(SVC_BUF_LOCK, &priv->svc_bufs[i].lock);
	return ret;
	}

	return xfer_sz;
	}

	/*
	* Send a FPGA image to privileged layers to write to the FPGA. When done
	* sending, free all service layer buffers we allocated in write_init.
	*/
	static int s10_ops_write(struct fpga_manager mgr, const char buf,
	size_t count)
	{
	struct s10_priv *priv = mgr->priv;
	struct device *dev = priv->client.dev;
	long wait_status;
	int sent = 0;
	int ret = 0;

	/*
	* Loop waiting for buffers to be returned. When a buffer is returned,
	* reuse it to send more data or free if if all data has been sent.
	*/
	while (count > 0 \|\| s10_free_buffer_count(mgr) != NUM_SVC_BUFS) {
	reinit_completion(&priv->status_return_completion);

	if (count > 0) {
	sent = s10_send_buf(mgr, buf, count);
	if (sent < 0)
	continue;

	count -= sent;
	buf += sent;
	} else {
	if (s10_free_buffers(mgr))
	return 0;

	ret = s10_svc_send_msg(
	priv, COMMAND_RECONFIG_DATA_CLAIM,
	NULL, 0);
	if (ret < 0)
	break;
	}

	/*
	* If callback hasn't already happened, wait for buffers to be
	* returned from service layer
	*/
	wait_status = 1; /* not timed out */
	if (!priv->status)
	wait_status = wait_for_completion_interruptible_timeout(
	&priv->status_return_completion,
	S10_BUFFER_TIMEOUT);

	if (test_and_clear_bit(SVC_STATUS_RECONFIG_BUFFER_DONE,
	&priv->status) \|\|
	test_and_clear_bit(SVC_STATUS_RECONFIG_BUFFER_SUBMITTED,
	&priv->status)) {
	ret = 0;
	continue;
	}

	if (test_and_clear_bit(SVC_STATUS_RECONFIG_ERROR,
	&priv->status)) {
	dev_err(dev, "ERROR - giving up - SVC_STATUS_RECONFIG_ERROR\n");
	ret = -EFAULT;
	break;
	}

	if (!wait_status) {
	dev_err(dev, "timeout waiting for svc layer buffers\n");
	ret = -ETIMEDOUT;
	break;
	}
	if (wait_status < 0) {
	ret = wait_status;
	dev_err(dev,
	"error (%d) waiting for svc layer buffers\n",
	ret);
	break;
	}
	}

	if (!s10_free_buffers(mgr))
	dev_err(dev, "%s not all buffers were freed\n", __func__);

	return ret;
	}

	static int s10_ops_write_complete(struct fpga_manager *mgr,
	struct fpga_image_info *info)
	{
	struct s10_priv *priv = mgr->priv;
	struct device *dev = priv->client.dev;
	unsigned long timeout;
	int ret;

	timeout = usecs_to_jiffies(info->config_complete_timeout_us);

	do {
	reinit_completion(&priv->status_return_completion);

	ret = s10_svc_send_msg(priv, COMMAND_RECONFIG_STATUS, NULL, 0);
	if (ret < 0)
	break;

	ret = wait_for_completion_interruptible_timeout(
	&priv->status_return_completion, timeout);
	if (!ret) {
	dev_err(dev,
	"timeout waiting for RECONFIG_COMPLETED\n");
	ret = -ETIMEDOUT;
	break;
	}
	if (ret < 0) {
	dev_err(dev,
	"error (%d) waiting for RECONFIG_COMPLETED\n",
	ret);
	break;
	}
	/* Not error or timeout, so ret is # of jiffies until timeout */
	timeout = ret;
	ret = 0;

	if (test_and_clear_bit(SVC_STATUS_RECONFIG_COMPLETED,
	&priv->status))
	break;

	if (test_and_clear_bit(SVC_STATUS_RECONFIG_ERROR,
	&priv->status)) {
	dev_err(dev, "ERROR - giving up - SVC_STATUS_RECONFIG_ERROR\n");
	ret = -EFAULT;
	break;
	}
	} while (1);

	stratix10_svc_done(priv->chan);

	return ret;
	}

	static enum fpga_mgr_states s10_ops_state(struct fpga_manager *mgr)
	{
	return FPGA_MGR_STATE_UNKNOWN;
	}

	static const struct fpga_manager_ops s10_ops = {
	.state = s10_ops_state,
	.write_init = s10_ops_write_init,
	.write = s10_ops_write,
	.write_complete = s10_ops_write_complete,
	};

	static int s10_probe(struct platform_device *pdev)
	{
	struct device *dev = &pdev->dev;
	struct s10_priv *priv;
	struct fpga_manager *mgr;
	int ret;

	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
	if (!priv)
	return -ENOMEM;

	priv->client.dev = dev;
	priv->client.receive_cb = s10_receive_callback;
	priv->client.priv = priv;

	priv->chan = stratix10_svc_request_channel_byname(&priv->client,
	SVC_CLIENT_FPGA);
	if (IS_ERR(priv->chan)) {
	dev_err(dev, "couldn't get service channel (%s)\n",
	SVC_CLIENT_FPGA);
	return PTR_ERR(priv->chan);
	}

	init_completion(&priv->status_return_completion);

	mgr = fpga_mgr_create(dev, "Stratix10 SOC FPGA Manager",
	&s10_ops, priv);
	if (!mgr) {
	dev_err(dev, "unable to create FPGA manager\n");
	ret = -ENOMEM;
	goto probe_err;
	}

	ret = fpga_mgr_register(mgr);
	if (ret) {
	dev_err(dev, "unable to register FPGA manager\n");
	fpga_mgr_free(mgr);
	goto probe_err;
	}

	platform_set_drvdata(pdev, mgr);
	return ret;

	probe_err:
	stratix10_svc_free_channel(priv->chan);
	return ret;
	}

	static int s10_remove(struct platform_device *pdev)
	{
	struct fpga_manager *mgr = platform_get_drvdata(pdev);
	struct s10_priv *priv = mgr->priv;

	fpga_mgr_unregister(mgr);
	stratix10_svc_free_channel(priv->chan);

	return 0;
	}

	static const struct of_device_id s10_of_match[] = {
	{ .compatible = "intel,stratix10-soc-fpga-mgr", },
	{},
	};

	MODULE_DEVICE_TABLE(of, s10_of_match);

	static struct platform_driver s10_driver = {
	.probe = s10_probe,
	.remove = s10_remove,
	.driver = {
	.name = "Stratix10 SoC FPGA manager",
	.of_match_table = of_match_ptr(s10_of_match),
	},
	};

	static int __init s10_init(void)
	{
	struct device_node *fw_np;
	struct device_node *np;
	int ret;

	fw_np = of_find_node_by_name(NULL, "svc");
	if (!fw_np)
	return -ENODEV;

	np = of_find_matching_node(fw_np, s10_of_match);
	if (!np)
	return -ENODEV;

	of_node_put(np);
	ret = of_platform_populate(fw_np, s10_of_match, NULL, NULL);
	if (ret)
	return ret;

	return platform_driver_register(&s10_driver);
	}

	static void __exit s10_exit(void)
	{
	return platform_driver_unregister(&s10_driver);
	}

	module_init(s10_init);
	module_exit(s10_exit);

	MODULE_AUTHOR("Alan Tull <atull@kernel.org>");
	MODULE_DESCRIPTION("Intel Stratix 10 SOC FPGA Manager");
	MODULE_LICENSE("GPL v2");