drivers/fpga/dfl-fme-pr.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0
 /*
  * Driver for FPGA Management Engine (FME) Partial Reconfiguration
  *
  * Copyright (C) 2017-2018 Intel Corporation, Inc.
  *
  * Authors:
  *   Kang Luwei <luwei.kang@intel.com>
  *   Xiao Guangrong <guangrong.xiao@linux.intel.com>
  *   Wu Hao <hao.wu@intel.com>
  *   Joseph Grecco <joe.grecco@intel.com>
  *   Enno Luebbers <enno.luebbers@intel.com>
  *   Tim Whisonant <tim.whisonant@intel.com>
  *   Ananda Ravuri <ananda.ravuri@intel.com>
  *   Christopher Rauer <christopher.rauer@intel.com>
  *   Henry Mitchel <henry.mitchel@intel.com>
  */

 #include <linux/types.h>
 #include <linux/device.h>
 #include <linux/vmalloc.h>
 #include <linux/uaccess.h>
 #include <linux/fpga/fpga-mgr.h>
 #include <linux/fpga/fpga-bridge.h>
 #include <linux/fpga/fpga-region.h>
 #include <linux/fpga-dfl.h>

 #include "dfl.h"
 #include "dfl-fme.h"
 #include "dfl-fme-pr.h"

 static struct dfl_fme_region *
 dfl_fme_region_find_by_port_id(struct dfl_fme *fme, int port_id)
 {
 	struct dfl_fme_region *fme_region;

 	list_for_each_entry(fme_region, &fme->region_list, node)
 		if (fme_region->port_id == port_id)
 			return fme_region;

 	return NULL;
 }

 static int dfl_fme_region_match(struct device *dev, const void *data)
 {
 	return dev->parent == data;
 }

 static struct fpga_region *dfl_fme_region_find(struct dfl_fme *fme, int port_id)
 {
 	struct dfl_fme_region *fme_region;
 	struct fpga_region *region;

 	fme_region = dfl_fme_region_find_by_port_id(fme, port_id);
 	if (!fme_region)
 		return NULL;

 	region = fpga_region_class_find(NULL, &fme_region->region->dev,
 					dfl_fme_region_match);
 	if (!region)
 		return NULL;

 	return region;
 }

 static int fme_pr(struct platform_device *pdev, unsigned long arg)
 {
 	struct dfl_feature_platform_data *pdata = dev_get_platdata(&pdev->dev);
 	void __user *argp = (void __user *)arg;
 	struct dfl_fpga_fme_port_pr port_pr;
 	struct fpga_image_info *info;
 	struct fpga_region *region;
 	void __iomem *fme_hdr;
 	struct dfl_fme *fme;
 	unsigned long minsz;
 	void *buf = NULL;
 	int ret = 0;
 	u64 v;

 	minsz = offsetofend(struct dfl_fpga_fme_port_pr, buffer_address);

 	if (copy_from_user(&port_pr, argp, minsz))
 		return -EFAULT;

 	if (port_pr.argsz < minsz || port_pr.flags)
 		return -EINVAL;

 	if (!IS_ALIGNED(port_pr.buffer_size, 4))
 		return -EINVAL;

 	/* get fme header region */
 	fme_hdr = dfl_get_feature_ioaddr_by_id(&pdev->dev,
 					       FME_FEATURE_ID_HEADER);

 	/* check port id */
 	v = readq(fme_hdr + FME_HDR_CAP);
 	if (port_pr.port_id >= FIELD_GET(FME_CAP_NUM_PORTS, v)) {
 		dev_dbg(&pdev->dev, "port number more than maximum\n");
 		return -EINVAL;
 	}

 	if (!access_ok(VERIFY_READ,
 		       (void __user *)(unsigned long)port_pr.buffer_address,
 		       port_pr.buffer_size))
 		return -EFAULT;

 	buf = vmalloc(port_pr.buffer_size);
 	if (!buf)
 		return -ENOMEM;

 	if (copy_from_user(buf,
 			   (void __user *)(unsigned long)port_pr.buffer_address,
 			   port_pr.buffer_size)) {
 		ret = -EFAULT;
 		goto free_exit;
 	}

 	/* prepare fpga_image_info for PR */
 	info = fpga_image_info_alloc(&pdev->dev);
 	if (!info) {
 		ret = -ENOMEM;
 		goto free_exit;
 	}

 	info->flags |= FPGA_MGR_PARTIAL_RECONFIG;

 	mutex_lock(&pdata->lock);
 	fme = dfl_fpga_pdata_get_private(pdata);
 	/* fme device has been unregistered. */
 	if (!fme) {
 		ret = -EINVAL;
 		goto unlock_exit;
 	}

 	region = dfl_fme_region_find(fme, port_pr.port_id);
 	if (!region) {
 		ret = -EINVAL;
 		goto unlock_exit;
 	}

 	fpga_image_info_free(region->info);

 	info->buf = buf;
 	info->count = port_pr.buffer_size;
 	info->region_id = port_pr.port_id;
 	region->info = info;

 	ret = fpga_region_program_fpga(region);

 	/*
 	 * it allows userspace to reset the PR region's logic by disabling and
 	 * reenabling the bridge to clear things out between accleration runs.
 	 * so no need to hold the bridges after partial reconfiguration.
 	 */
 	if (region->get_bridges)
 		fpga_bridges_put(&region->bridge_list);

 	put_device(&region->dev);
 unlock_exit:
 	mutex_unlock(&pdata->lock);
 free_exit:
 	vfree(buf);
 	if (copy_to_user((void __user *)arg, &port_pr, minsz))
 		return -EFAULT;

 	return ret;
 }

 /**
  * dfl_fme_create_mgr - create fpga mgr platform device as child device
  *
  * @pdata: fme platform_device's pdata
  *
  * Return: mgr platform device if successful, and error code otherwise.
  */
 static struct platform_device *
 dfl_fme_create_mgr(struct dfl_feature_platform_data *pdata,
 		   struct dfl_feature *feature)
 {
 	struct platform_device *mgr, *fme = pdata->dev;
 	struct dfl_fme_mgr_pdata mgr_pdata;
 	int ret = -ENOMEM;

 	if (!feature->ioaddr)
 		return ERR_PTR(-ENODEV);

 	mgr_pdata.ioaddr = feature->ioaddr;

 	/*
 	 * Each FME has only one fpga-mgr, so allocate platform device using
 	 * the same FME platform device id.
 	 */
 	mgr = platform_device_alloc(DFL_FPGA_FME_MGR, fme->id);
 	if (!mgr)
 		return ERR_PTR(ret);

 	mgr->dev.parent = &fme->dev;

 	ret = platform_device_add_data(mgr, &mgr_pdata, sizeof(mgr_pdata));
 	if (ret)
 		goto create_mgr_err;

 	ret = platform_device_add(mgr);
 	if (ret)
 		goto create_mgr_err;

 	return mgr;

 create_mgr_err:
 	platform_device_put(mgr);
 	return ERR_PTR(ret);
 }

 /**
  * dfl_fme_destroy_mgr - destroy fpga mgr platform device
  * @pdata: fme platform device's pdata
  */
 static void dfl_fme_destroy_mgr(struct dfl_feature_platform_data *pdata)
 {
 	struct dfl_fme *priv = dfl_fpga_pdata_get_private(pdata);

 	platform_device_unregister(priv->mgr);
 }

 /**
  * dfl_fme_create_bridge - create fme fpga bridge platform device as child
  *
  * @pdata: fme platform device's pdata
  * @port_id: port id for the bridge to be created.
  *
  * Return: bridge platform device if successful, and error code otherwise.
  */
 static struct dfl_fme_bridge *
 dfl_fme_create_bridge(struct dfl_feature_platform_data *pdata, int port_id)
 {
 	struct device *dev = &pdata->dev->dev;
 	struct dfl_fme_br_pdata br_pdata;
 	struct dfl_fme_bridge *fme_br;
 	int ret = -ENOMEM;

 	fme_br = devm_kzalloc(dev, sizeof(*fme_br), GFP_KERNEL);
 	if (!fme_br)
 		return ERR_PTR(ret);

 	br_pdata.cdev = pdata->dfl_cdev;
 	br_pdata.port_id = port_id;

 	fme_br->br = platform_device_alloc(DFL_FPGA_FME_BRIDGE,
 					   PLATFORM_DEVID_AUTO);
 	if (!fme_br->br)
 		return ERR_PTR(ret);

 	fme_br->br->dev.parent = dev;

 	ret = platform_device_add_data(fme_br->br, &br_pdata, sizeof(br_pdata));
 	if (ret)
 		goto create_br_err;

 	ret = platform_device_add(fme_br->br);
 	if (ret)
 		goto create_br_err;

 	return fme_br;

 create_br_err:
 	platform_device_put(fme_br->br);
 	return ERR_PTR(ret);
 }

 /**
  * dfl_fme_destroy_bridge - destroy fpga bridge platform device
  * @fme_br: fme bridge to destroy
  */
 static void dfl_fme_destroy_bridge(struct dfl_fme_bridge *fme_br)
 {
 	platform_device_unregister(fme_br->br);
 }

 /**
  * dfl_fme_destroy_bridge - destroy all fpga bridge platform device
  * @pdata: fme platform device's pdata
  */
 static void dfl_fme_destroy_bridges(struct dfl_feature_platform_data *pdata)
 {
 	struct dfl_fme *priv = dfl_fpga_pdata_get_private(pdata);
 	struct dfl_fme_bridge *fbridge, *tmp;

 	list_for_each_entry_safe(fbridge, tmp, &priv->bridge_list, node) {
 		list_del(&fbridge->node);
 		dfl_fme_destroy_bridge(fbridge);
 	}
 }

 /**
  * dfl_fme_create_region - create fpga region platform device as child
  *
  * @pdata: fme platform device's pdata
  * @mgr: mgr platform device needed for region
  * @br: br platform device needed for region
  * @port_id: port id
  *
  * Return: fme region if successful, and error code otherwise.
  */
 static struct dfl_fme_region *
 dfl_fme_create_region(struct dfl_feature_platform_data *pdata,
 		      struct platform_device *mgr,
 		      struct platform_device *br, int port_id)
 {
 	struct dfl_fme_region_pdata region_pdata;
 	struct device *dev = &pdata->dev->dev;
 	struct dfl_fme_region *fme_region;
 	int ret = -ENOMEM;

 	fme_region = devm_kzalloc(dev, sizeof(*fme_region), GFP_KERNEL);
 	if (!fme_region)
 		return ERR_PTR(ret);

 	region_pdata.mgr = mgr;
 	region_pdata.br = br;

 	/*
 	 * Each FPGA device may have more than one port, so allocate platform
 	 * device using the same port platform device id.
 	 */
 	fme_region->region = platform_device_alloc(DFL_FPGA_FME_REGION, br->id);
 	if (!fme_region->region)
 		return ERR_PTR(ret);

 	fme_region->region->dev.parent = dev;

 	ret = platform_device_add_data(fme_region->region, &region_pdata,
 				       sizeof(region_pdata));
 	if (ret)
 		goto create_region_err;

 	ret = platform_device_add(fme_region->region);
 	if (ret)
 		goto create_region_err;

 	fme_region->port_id = port_id;

 	return fme_region;

 create_region_err:
 	platform_device_put(fme_region->region);
 	return ERR_PTR(ret);
 }

 /**
  * dfl_fme_destroy_region - destroy fme region
  * @fme_region: fme region to destroy
  */
 static void dfl_fme_destroy_region(struct dfl_fme_region *fme_region)
 {
 	platform_device_unregister(fme_region->region);
 }

 /**
  * dfl_fme_destroy_regions - destroy all fme regions
  * @pdata: fme platform device's pdata
  */
 static void dfl_fme_destroy_regions(struct dfl_feature_platform_data *pdata)
 {
 	struct dfl_fme *priv = dfl_fpga_pdata_get_private(pdata);
 	struct dfl_fme_region *fme_region, *tmp;

 	list_for_each_entry_safe(fme_region, tmp, &priv->region_list, node) {
 		list_del(&fme_region->node);
 		dfl_fme_destroy_region(fme_region);
 	}
 }

 static int pr_mgmt_init(struct platform_device *pdev,
 			struct dfl_feature *feature)
 {
 	struct dfl_feature_platform_data *pdata = dev_get_platdata(&pdev->dev);
 	struct dfl_fme_region *fme_region;
 	struct dfl_fme_bridge *fme_br;
 	struct platform_device *mgr;
 	struct dfl_fme *priv;
 	void __iomem *fme_hdr;
 	int ret = -ENODEV, i = 0;
 	u64 fme_cap, port_offset;

 	fme_hdr = dfl_get_feature_ioaddr_by_id(&pdev->dev,
 					       FME_FEATURE_ID_HEADER);

 	mutex_lock(&pdata->lock);
 	priv = dfl_fpga_pdata_get_private(pdata);

 	/* Initialize the region and bridge sub device list */
 	INIT_LIST_HEAD(&priv->region_list);
 	INIT_LIST_HEAD(&priv->bridge_list);

 	/* Create fpga mgr platform device */
 	mgr = dfl_fme_create_mgr(pdata, feature);
 	if (IS_ERR(mgr)) {
 		dev_err(&pdev->dev, "fail to create fpga mgr pdev\n");
 		goto unlock;
 	}

 	priv->mgr = mgr;

 	/* Read capability register to check number of regions and bridges */
 	fme_cap = readq(fme_hdr + FME_HDR_CAP);
 	for (; i < FIELD_GET(FME_CAP_NUM_PORTS, fme_cap); i++) {
 		port_offset = readq(fme_hdr + FME_HDR_PORT_OFST(i));
 		if (!(port_offset & FME_PORT_OFST_IMP))
 			continue;

 		/* Create bridge for each port */
 		fme_br = dfl_fme_create_bridge(pdata, i);
 		if (IS_ERR(fme_br)) {
 			ret = PTR_ERR(fme_br);
 			goto destroy_region;
 		}

 		list_add(&fme_br->node, &priv->bridge_list);

 		/* Create region for each port */
 		fme_region = dfl_fme_create_region(pdata, mgr,
 						   fme_br->br, i);
 		if (IS_ERR(fme_region)) {
 			ret = PTR_ERR(fme_region);
 			goto destroy_region;
 		}

 		list_add(&fme_region->node, &priv->region_list);
 	}
 	mutex_unlock(&pdata->lock);

 	return 0;

 destroy_region:
 	dfl_fme_destroy_regions(pdata);
 	dfl_fme_destroy_bridges(pdata);
 	dfl_fme_destroy_mgr(pdata);
 unlock:
 	mutex_unlock(&pdata->lock);
 	return ret;
 }

 static void pr_mgmt_uinit(struct platform_device *pdev,
 			  struct dfl_feature *feature)
 {
 	struct dfl_feature_platform_data *pdata = dev_get_platdata(&pdev->dev);
 	struct dfl_fme *priv;

 	mutex_lock(&pdata->lock);
 	priv = dfl_fpga_pdata_get_private(pdata);

 	dfl_fme_destroy_regions(pdata);
 	dfl_fme_destroy_bridges(pdata);
 	dfl_fme_destroy_mgr(pdata);
 	mutex_unlock(&pdata->lock);
 }

 static long fme_pr_ioctl(struct platform_device *pdev,
 			 struct dfl_feature *feature,
 			 unsigned int cmd, unsigned long arg)
 {
 	long ret;

 	switch (cmd) {
 	case DFL_FPGA_FME_PORT_PR:
 		ret = fme_pr(pdev, arg);
 		break;
 	default:
 		ret = -ENODEV;
 	}

 	return ret;
 }

 const struct dfl_feature_ops pr_mgmt_ops = {
 	.init = pr_mgmt_init,
 	.uinit = pr_mgmt_uinit,
 	.ioctl = fme_pr_ioctl,
 };
	// SPDX-License-Identifier: GPL-2.0
	/*
	* Driver for FPGA Management Engine (FME) Partial Reconfiguration
	*
	* Copyright (C) 2017-2018 Intel Corporation, Inc.
	*
	* Authors:
	* Kang Luwei <luwei.kang@intel.com>
	* Xiao Guangrong <guangrong.xiao@linux.intel.com>
	* Wu Hao <hao.wu@intel.com>
	* Joseph Grecco <joe.grecco@intel.com>
	* Enno Luebbers <enno.luebbers@intel.com>
	* Tim Whisonant <tim.whisonant@intel.com>
	* Ananda Ravuri <ananda.ravuri@intel.com>
	* Christopher Rauer <christopher.rauer@intel.com>
	* Henry Mitchel <henry.mitchel@intel.com>
	*/

	#include <linux/types.h>
	#include <linux/device.h>
	#include <linux/vmalloc.h>
	#include <linux/uaccess.h>
	#include <linux/fpga/fpga-mgr.h>
	#include <linux/fpga/fpga-bridge.h>
	#include <linux/fpga/fpga-region.h>
	#include <linux/fpga-dfl.h>

	#include "dfl.h"
	#include "dfl-fme.h"
	#include "dfl-fme-pr.h"

	static struct dfl_fme_region *
	dfl_fme_region_find_by_port_id(struct dfl_fme *fme, int port_id)
	{
	struct dfl_fme_region *fme_region;

	list_for_each_entry(fme_region, &fme->region_list, node)
	if (fme_region->port_id == port_id)
	return fme_region;

	return NULL;
	}

	static int dfl_fme_region_match(struct device dev, const void data)
	{
	return dev->parent == data;
	}

	static struct fpga_region dfl_fme_region_find(struct dfl_fme fme, int port_id)
	{
	struct dfl_fme_region *fme_region;
	struct fpga_region *region;

	fme_region = dfl_fme_region_find_by_port_id(fme, port_id);
	if (!fme_region)
	return NULL;

	region = fpga_region_class_find(NULL, &fme_region->region->dev,
	dfl_fme_region_match);
	if (!region)
	return NULL;

	return region;
	}

	static int fme_pr(struct platform_device *pdev, unsigned long arg)
	{
	struct dfl_feature_platform_data *pdata = dev_get_platdata(&pdev->dev);
	void __user argp = (void __user )arg;
	struct dfl_fpga_fme_port_pr port_pr;
	struct fpga_image_info *info;
	struct fpga_region *region;
	void __iomem *fme_hdr;
	struct dfl_fme *fme;
	unsigned long minsz;
	void *buf = NULL;
	int ret = 0;
	u64 v;

	minsz = offsetofend(struct dfl_fpga_fme_port_pr, buffer_address);

	if (copy_from_user(&port_pr, argp, minsz))
	return -EFAULT;

	if (port_pr.argsz < minsz \|\| port_pr.flags)
	return -EINVAL;

	if (!IS_ALIGNED(port_pr.buffer_size, 4))
	return -EINVAL;

	/* get fme header region */
	fme_hdr = dfl_get_feature_ioaddr_by_id(&pdev->dev,
	FME_FEATURE_ID_HEADER);

	/* check port id */
	v = readq(fme_hdr + FME_HDR_CAP);
	if (port_pr.port_id >= FIELD_GET(FME_CAP_NUM_PORTS, v)) {
	dev_dbg(&pdev->dev, "port number more than maximum\n");
	return -EINVAL;
	}

	if (!access_ok(VERIFY_READ,
	(void __user *)(unsigned long)port_pr.buffer_address,
	port_pr.buffer_size))
	return -EFAULT;

	buf = vmalloc(port_pr.buffer_size);
	if (!buf)
	return -ENOMEM;

	if (copy_from_user(buf,
	(void __user *)(unsigned long)port_pr.buffer_address,
	port_pr.buffer_size)) {
	ret = -EFAULT;
	goto free_exit;
	}

	/* prepare fpga_image_info for PR */
	info = fpga_image_info_alloc(&pdev->dev);
	if (!info) {
	ret = -ENOMEM;
	goto free_exit;
	}

	info->flags \|= FPGA_MGR_PARTIAL_RECONFIG;

	mutex_lock(&pdata->lock);
	fme = dfl_fpga_pdata_get_private(pdata);
	/* fme device has been unregistered. */
	if (!fme) {
	ret = -EINVAL;
	goto unlock_exit;
	}

	region = dfl_fme_region_find(fme, port_pr.port_id);
	if (!region) {
	ret = -EINVAL;
	goto unlock_exit;
	}

	fpga_image_info_free(region->info);

	info->buf = buf;
	info->count = port_pr.buffer_size;
	info->region_id = port_pr.port_id;
	region->info = info;

	ret = fpga_region_program_fpga(region);

	/*
	* it allows userspace to reset the PR region's logic by disabling and
	* reenabling the bridge to clear things out between accleration runs.
	* so no need to hold the bridges after partial reconfiguration.
	*/
	if (region->get_bridges)
	fpga_bridges_put(&region->bridge_list);

	put_device(&region->dev);
	unlock_exit:
	mutex_unlock(&pdata->lock);
	free_exit:
	vfree(buf);
	if (copy_to_user((void __user *)arg, &port_pr, minsz))
	return -EFAULT;

	return ret;
	}

	/**
	* dfl_fme_create_mgr - create fpga mgr platform device as child device
	*
	* @pdata: fme platform_device's pdata
	*
	* Return: mgr platform device if successful, and error code otherwise.
	*/
	static struct platform_device *
	dfl_fme_create_mgr(struct dfl_feature_platform_data *pdata,
	struct dfl_feature *feature)
	{
	struct platform_device mgr, fme = pdata->dev;
	struct dfl_fme_mgr_pdata mgr_pdata;
	int ret = -ENOMEM;

	if (!feature->ioaddr)
	return ERR_PTR(-ENODEV);

	mgr_pdata.ioaddr = feature->ioaddr;

	/*
	* Each FME has only one fpga-mgr, so allocate platform device using
	* the same FME platform device id.
	*/
	mgr = platform_device_alloc(DFL_FPGA_FME_MGR, fme->id);
	if (!mgr)
	return ERR_PTR(ret);

	mgr->dev.parent = &fme->dev;

	ret = platform_device_add_data(mgr, &mgr_pdata, sizeof(mgr_pdata));
	if (ret)
	goto create_mgr_err;

	ret = platform_device_add(mgr);
	if (ret)
	goto create_mgr_err;

	return mgr;

	create_mgr_err:
	platform_device_put(mgr);
	return ERR_PTR(ret);
	}

	/**
	* dfl_fme_destroy_mgr - destroy fpga mgr platform device
	* @pdata: fme platform device's pdata
	*/
	static void dfl_fme_destroy_mgr(struct dfl_feature_platform_data *pdata)
	{
	struct dfl_fme *priv = dfl_fpga_pdata_get_private(pdata);

	platform_device_unregister(priv->mgr);
	}

	/**
	* dfl_fme_create_bridge - create fme fpga bridge platform device as child
	*
	* @pdata: fme platform device's pdata
	* @port_id: port id for the bridge to be created.
	*
	* Return: bridge platform device if successful, and error code otherwise.
	*/
	static struct dfl_fme_bridge *
	dfl_fme_create_bridge(struct dfl_feature_platform_data *pdata, int port_id)
	{
	struct device *dev = &pdata->dev->dev;
	struct dfl_fme_br_pdata br_pdata;
	struct dfl_fme_bridge *fme_br;
	int ret = -ENOMEM;

	fme_br = devm_kzalloc(dev, sizeof(*fme_br), GFP_KERNEL);
	if (!fme_br)
	return ERR_PTR(ret);

	br_pdata.cdev = pdata->dfl_cdev;
	br_pdata.port_id = port_id;

	fme_br->br = platform_device_alloc(DFL_FPGA_FME_BRIDGE,
	PLATFORM_DEVID_AUTO);
	if (!fme_br->br)
	return ERR_PTR(ret);

	fme_br->br->dev.parent = dev;

	ret = platform_device_add_data(fme_br->br, &br_pdata, sizeof(br_pdata));
	if (ret)
	goto create_br_err;

	ret = platform_device_add(fme_br->br);
	if (ret)
	goto create_br_err;

	return fme_br;

	create_br_err:
	platform_device_put(fme_br->br);
	return ERR_PTR(ret);
	}

	/**
	* dfl_fme_destroy_bridge - destroy fpga bridge platform device
	* @fme_br: fme bridge to destroy
	*/
	static void dfl_fme_destroy_bridge(struct dfl_fme_bridge *fme_br)
	{
	platform_device_unregister(fme_br->br);
	}

	/**
	* dfl_fme_destroy_bridge - destroy all fpga bridge platform device
	* @pdata: fme platform device's pdata
	*/
	static void dfl_fme_destroy_bridges(struct dfl_feature_platform_data *pdata)
	{
	struct dfl_fme *priv = dfl_fpga_pdata_get_private(pdata);
	struct dfl_fme_bridge fbridge, tmp;

	list_for_each_entry_safe(fbridge, tmp, &priv->bridge_list, node) {
	list_del(&fbridge->node);
	dfl_fme_destroy_bridge(fbridge);
	}
	}

	/**
	* dfl_fme_create_region - create fpga region platform device as child
	*
	* @pdata: fme platform device's pdata
	* @mgr: mgr platform device needed for region
	* @br: br platform device needed for region
	* @port_id: port id
	*
	* Return: fme region if successful, and error code otherwise.
	*/
	static struct dfl_fme_region *
	dfl_fme_create_region(struct dfl_feature_platform_data *pdata,
	struct platform_device *mgr,
	struct platform_device *br, int port_id)
	{
	struct dfl_fme_region_pdata region_pdata;
	struct device *dev = &pdata->dev->dev;
	struct dfl_fme_region *fme_region;
	int ret = -ENOMEM;

	fme_region = devm_kzalloc(dev, sizeof(*fme_region), GFP_KERNEL);
	if (!fme_region)
	return ERR_PTR(ret);

	region_pdata.mgr = mgr;
	region_pdata.br = br;

	/*
	* Each FPGA device may have more than one port, so allocate platform
	* device using the same port platform device id.
	*/
	fme_region->region = platform_device_alloc(DFL_FPGA_FME_REGION, br->id);
	if (!fme_region->region)
	return ERR_PTR(ret);

	fme_region->region->dev.parent = dev;

	ret = platform_device_add_data(fme_region->region, &region_pdata,
	sizeof(region_pdata));
	if (ret)
	goto create_region_err;

	ret = platform_device_add(fme_region->region);
	if (ret)
	goto create_region_err;

	fme_region->port_id = port_id;

	return fme_region;

	create_region_err:
	platform_device_put(fme_region->region);
	return ERR_PTR(ret);
	}

	/**
	* dfl_fme_destroy_region - destroy fme region
	* @fme_region: fme region to destroy
	*/
	static void dfl_fme_destroy_region(struct dfl_fme_region *fme_region)
	{
	platform_device_unregister(fme_region->region);
	}

	/**
	* dfl_fme_destroy_regions - destroy all fme regions
	* @pdata: fme platform device's pdata
	*/
	static void dfl_fme_destroy_regions(struct dfl_feature_platform_data *pdata)
	{
	struct dfl_fme *priv = dfl_fpga_pdata_get_private(pdata);
	struct dfl_fme_region fme_region, tmp;

	list_for_each_entry_safe(fme_region, tmp, &priv->region_list, node) {
	list_del(&fme_region->node);
	dfl_fme_destroy_region(fme_region);
	}
	}

	static int pr_mgmt_init(struct platform_device *pdev,
	struct dfl_feature *feature)
	{
	struct dfl_feature_platform_data *pdata = dev_get_platdata(&pdev->dev);
	struct dfl_fme_region *fme_region;
	struct dfl_fme_bridge *fme_br;
	struct platform_device *mgr;
	struct dfl_fme *priv;
	void __iomem *fme_hdr;
	int ret = -ENODEV, i = 0;
	u64 fme_cap, port_offset;

	fme_hdr = dfl_get_feature_ioaddr_by_id(&pdev->dev,
	FME_FEATURE_ID_HEADER);

	mutex_lock(&pdata->lock);
	priv = dfl_fpga_pdata_get_private(pdata);

	/* Initialize the region and bridge sub device list */
	INIT_LIST_HEAD(&priv->region_list);
	INIT_LIST_HEAD(&priv->bridge_list);

	/* Create fpga mgr platform device */
	mgr = dfl_fme_create_mgr(pdata, feature);
	if (IS_ERR(mgr)) {
	dev_err(&pdev->dev, "fail to create fpga mgr pdev\n");
	goto unlock;
	}

	priv->mgr = mgr;

	/* Read capability register to check number of regions and bridges */
	fme_cap = readq(fme_hdr + FME_HDR_CAP);
	for (; i < FIELD_GET(FME_CAP_NUM_PORTS, fme_cap); i++) {
	port_offset = readq(fme_hdr + FME_HDR_PORT_OFST(i));
	if (!(port_offset & FME_PORT_OFST_IMP))
	continue;

	/* Create bridge for each port */
	fme_br = dfl_fme_create_bridge(pdata, i);
	if (IS_ERR(fme_br)) {
	ret = PTR_ERR(fme_br);
	goto destroy_region;
	}

	list_add(&fme_br->node, &priv->bridge_list);

	/* Create region for each port */
	fme_region = dfl_fme_create_region(pdata, mgr,
	fme_br->br, i);
	if (IS_ERR(fme_region)) {
	ret = PTR_ERR(fme_region);
	goto destroy_region;
	}

	list_add(&fme_region->node, &priv->region_list);
	}
	mutex_unlock(&pdata->lock);

	return 0;

	destroy_region:
	dfl_fme_destroy_regions(pdata);
	dfl_fme_destroy_bridges(pdata);
	dfl_fme_destroy_mgr(pdata);
	unlock:
	mutex_unlock(&pdata->lock);
	return ret;
	}

	static void pr_mgmt_uinit(struct platform_device *pdev,
	struct dfl_feature *feature)
	{
	struct dfl_feature_platform_data *pdata = dev_get_platdata(&pdev->dev);
	struct dfl_fme *priv;

	mutex_lock(&pdata->lock);
	priv = dfl_fpga_pdata_get_private(pdata);

	dfl_fme_destroy_regions(pdata);
	dfl_fme_destroy_bridges(pdata);
	dfl_fme_destroy_mgr(pdata);
	mutex_unlock(&pdata->lock);
	}

	static long fme_pr_ioctl(struct platform_device *pdev,
	struct dfl_feature *feature,
	unsigned int cmd, unsigned long arg)
	{
	long ret;

	switch (cmd) {
	case DFL_FPGA_FME_PORT_PR:
	ret = fme_pr(pdev, arg);
	break;
	default:
	ret = -ENODEV;
	}

	return ret;
	}

	const struct dfl_feature_ops pr_mgmt_ops = {
	.init = pr_mgmt_init,
	.uinit = pr_mgmt_uinit,
	.ioctl = fme_pr_ioctl,
	};