[linux-block.git] / drivers / fpga / of-fpga-region.c

// SPDX-License-Identifier: GPL-2.0
/*
 * FPGA Region - Device Tree support for FPGA programming under Linux
 *
 *  Copyright (C) 2013-2016 Altera Corporation
 *  Copyright (C) 2017 Intel Corporation
 */
#include <linux/fpga/fpga-bridge.h>
#include <linux/fpga/fpga-mgr.h>
#include <linux/fpga/fpga-region.h>
#include <linux/idr.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/of_platform.h>
#include <linux/slab.h>
#include <linux/spinlock.h>

static const struct of_device_id fpga_region_of_match[] = {
	{ .compatible = "fpga-region", },
	{},
};
MODULE_DEVICE_TABLE(of, fpga_region_of_match);

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

/**
 * of_fpga_region_find - find FPGA region
 * @np: device node of FPGA Region
 *
 * Caller will need to put_device(&region->dev) when done.
 *
 * Returns FPGA Region struct or NULL
 */
static struct fpga_region *of_fpga_region_find(struct device_node *np)
{
	return fpga_region_class_find(NULL, np, fpga_region_of_node_match);
}

/**
 * of_fpga_region_get_mgr - get reference for FPGA manager
 * @np: device node of FPGA region
 *
 * Get FPGA Manager from "fpga-mgr" property or from ancestor region.
 *
 * Caller should call fpga_mgr_put() when done with manager.
 *
 * Return: fpga manager struct or IS_ERR() condition containing error code.
 */
static struct fpga_manager *of_fpga_region_get_mgr(struct device_node *np)
{
	struct device_node  *mgr_node;
	struct fpga_manager *mgr;

	of_node_get(np);
	while (np) {
		if (of_device_is_compatible(np, "fpga-region")) {
			mgr_node = of_parse_phandle(np, "fpga-mgr", 0);
			if (mgr_node) {
				mgr = of_fpga_mgr_get(mgr_node);
				of_node_put(mgr_node);
				of_node_put(np);
				return mgr;
			}
		}
		np = of_get_next_parent(np);
	}
	of_node_put(np);

	return ERR_PTR(-EINVAL);
}

/**
 * of_fpga_region_get_bridges - create a list of bridges
 * @region: FPGA region
 *
 * Create a list of bridges including the parent bridge and the bridges
 * specified by "fpga-bridges" property.  Note that the
 * fpga_bridges_enable/disable/put functions are all fine with an empty list
 * if that happens.
 *
 * Caller should call fpga_bridges_put(&region->bridge_list) when
 * done with the bridges.
 *
 * Return 0 for success (even if there are no bridges specified)
 * or -EBUSY if any of the bridges are in use.
 */
static int of_fpga_region_get_bridges(struct fpga_region *region)
{
	struct device *dev = &region->dev;
	struct device_node *region_np = dev->of_node;
	struct fpga_image_info *info = region->info;
	struct device_node *br, *np, *parent_br = NULL;
	int i, ret;

	/* If parent is a bridge, add to list */
	ret = of_fpga_bridge_get_to_list(region_np->parent, info,
					 &region->bridge_list);

	/* -EBUSY means parent is a bridge that is under use. Give up. */
	if (ret == -EBUSY)
		return ret;

	/* Zero return code means parent was a bridge and was added to list. */
	if (!ret)
		parent_br = region_np->parent;

	/* If overlay has a list of bridges, use it. */
	br = of_parse_phandle(info->overlay, "fpga-bridges", 0);
	if (br) {
		of_node_put(br);
		np = info->overlay;
	} else {
		np = region_np;
	}

	for (i = 0; ; i++) {
		br = of_parse_phandle(np, "fpga-bridges", i);
		if (!br)
			break;

		/* If parent bridge is in list, skip it. */
		if (br == parent_br) {
			of_node_put(br);
			continue;
		}

		/* If node is a bridge, get it and add to list */
		ret = of_fpga_bridge_get_to_list(br, info,
						 &region->bridge_list);
		of_node_put(br);

		/* If any of the bridges are in use, give up */
		if (ret == -EBUSY) {
			fpga_bridges_put(&region->bridge_list);
			return -EBUSY;
		}
	}

	return 0;
}

/**
 * child_regions_with_firmware
 * @overlay: device node of the overlay
 *
 * If the overlay adds child FPGA regions, they are not allowed to have
 * firmware-name property.
 *
 * Return 0 for OK or -EINVAL if child FPGA region adds firmware-name.
 */
static int child_regions_with_firmware(struct device_node *overlay)
{
	struct device_node *child_region;
	const char *child_firmware_name;
	int ret = 0;

	of_node_get(overlay);

	child_region = of_find_matching_node(overlay, fpga_region_of_match);
	while (child_region) {
		if (!of_property_read_string(child_region, "firmware-name",
					     &child_firmware_name)) {
			ret = -EINVAL;
			break;
		}
		child_region = of_find_matching_node(child_region,
						     fpga_region_of_match);
	}

	of_node_put(child_region);

	if (ret)
		pr_err("firmware-name not allowed in child FPGA region: %pOF",
		       child_region);

	return ret;
}

/**
 * of_fpga_region_parse_ov - parse and check overlay applied to region
 *
 * @region: FPGA region
 * @overlay: overlay applied to the FPGA region
 *
 * Given an overlay applied to a FPGA region, parse the FPGA image specific
 * info in the overlay and do some checking.
 *
 * Returns:
 *   NULL if overlay doesn't direct us to program the FPGA.
 *   fpga_image_info struct if there is an image to program.
 *   error code for invalid overlay.
 */
static struct fpga_image_info *of_fpga_region_parse_ov(
						struct fpga_region *region,
						struct device_node *overlay)
{
	struct device *dev = &region->dev;
	struct fpga_image_info *info;
	const char *firmware_name;
	int ret;

	if (region->info) {
		dev_err(dev, "Region already has overlay applied.\n");
		return ERR_PTR(-EINVAL);
	}

	/*
	 * Reject overlay if child FPGA Regions added in the overlay have
	 * firmware-name property (would mean that an FPGA region that has
	 * not been added to the live tree yet is doing FPGA programming).
	 */
	ret = child_regions_with_firmware(overlay);
	if (ret)
		return ERR_PTR(ret);

	info = fpga_image_info_alloc(dev);
	if (!info)
		return ERR_PTR(-ENOMEM);

	info->overlay = overlay;

	/* Read FPGA region properties from the overlay */
	if (of_property_read_bool(overlay, "partial-fpga-config"))
		info->flags |= FPGA_MGR_PARTIAL_RECONFIG;

	if (of_property_read_bool(overlay, "external-fpga-config"))
		info->flags |= FPGA_MGR_EXTERNAL_CONFIG;

	if (of_property_read_bool(overlay, "encrypted-fpga-config"))
		info->flags |= FPGA_MGR_ENCRYPTED_BITSTREAM;

	if (!of_property_read_string(overlay, "firmware-name",
				     &firmware_name)) {
		info->firmware_name = devm_kstrdup(dev, firmware_name,
						   GFP_KERNEL);
		if (!info->firmware_name)
			return ERR_PTR(-ENOMEM);
	}

	of_property_read_u32(overlay, "region-unfreeze-timeout-us",
			     &info->enable_timeout_us);

	of_property_read_u32(overlay, "region-freeze-timeout-us",
			     &info->disable_timeout_us);

	of_property_read_u32(overlay, "config-complete-timeout-us",
			     &info->config_complete_timeout_us);

	/* If overlay is not programming the FPGA, don't need FPGA image info */
	if (!info->firmware_name) {
		ret = 0;
		goto ret_no_info;
	}

	/*
	 * If overlay informs us FPGA was externally programmed, specifying
	 * firmware here would be ambiguous.
	 */
	if (info->flags & FPGA_MGR_EXTERNAL_CONFIG) {
		dev_err(dev, "error: specified firmware and external-fpga-config");
		ret = -EINVAL;
		goto ret_no_info;
	}

	return info;
ret_no_info:
	fpga_image_info_free(info);
	return ERR_PTR(ret);
}

/**
 * of_fpga_region_notify_pre_apply - pre-apply overlay notification
 *
 * @region: FPGA region that the overlay was applied to
 * @nd: overlay notification data
 *
 * Called when an overlay targeted to a FPGA Region is about to be applied.
 * Parses the overlay for properties that influence how the FPGA will be
 * programmed and does some checking. If the checks pass, programs the FPGA.
 * If the checks fail, overlay is rejected and does not get added to the
 * live tree.
 *
 * Returns 0 for success or negative error code for failure.
 */
static int of_fpga_region_notify_pre_apply(struct fpga_region *region,
					   struct of_overlay_notify_data *nd)
{
	struct device *dev = &region->dev;
	struct fpga_image_info *info;
	int ret;

	info = of_fpga_region_parse_ov(region, nd->overlay);
	if (IS_ERR(info))
		return PTR_ERR(info);

	/* If overlay doesn't program the FPGA, accept it anyway. */
	if (!info)
		return 0;

	if (region->info) {
		dev_err(dev, "Region already has overlay applied.\n");
		return -EINVAL;
	}

	region->info = info;
	ret = fpga_region_program_fpga(region);
	if (ret) {
		/* error; reject overlay */
		fpga_image_info_free(info);
		region->info = NULL;
	}

	return ret;
}

/**
 * of_fpga_region_notify_post_remove - post-remove overlay notification
 *
 * @region: FPGA region that was targeted by the overlay that was removed
 * @nd: overlay notification data
 *
 * Called after an overlay has been removed if the overlay's target was a
 * FPGA region.
 */
static void of_fpga_region_notify_post_remove(struct fpga_region *region,
					      struct of_overlay_notify_data *nd)
{
	fpga_bridges_disable(&region->bridge_list);
	fpga_bridges_put(&region->bridge_list);
	fpga_image_info_free(region->info);
	region->info = NULL;
}

/**
 * of_fpga_region_notify - reconfig notifier for dynamic DT changes
 * @nb:		notifier block
 * @action:	notifier action
 * @arg:	reconfig data
 *
 * This notifier handles programming a FPGA when a "firmware-name" property is
 * added to a fpga-region.
 *
 * Returns NOTIFY_OK or error if FPGA programming fails.
 */
static int of_fpga_region_notify(struct notifier_block *nb,
				 unsigned long action, void *arg)
{
	struct of_overlay_notify_data *nd = arg;
	struct fpga_region *region;
	int ret;

	switch (action) {
	case OF_OVERLAY_PRE_APPLY:
		pr_debug("%s OF_OVERLAY_PRE_APPLY\n", __func__);
		break;
	case OF_OVERLAY_POST_APPLY:
		pr_debug("%s OF_OVERLAY_POST_APPLY\n", __func__);
		return NOTIFY_OK;       /* not for us */
	case OF_OVERLAY_PRE_REMOVE:
		pr_debug("%s OF_OVERLAY_PRE_REMOVE\n", __func__);
		return NOTIFY_OK;       /* not for us */
	case OF_OVERLAY_POST_REMOVE:
		pr_debug("%s OF_OVERLAY_POST_REMOVE\n", __func__);
		break;
	default:			/* should not happen */
		return NOTIFY_OK;
	}

	region = of_fpga_region_find(nd->target);
	if (!region)
		return NOTIFY_OK;

	ret = 0;
	switch (action) {
	case OF_OVERLAY_PRE_APPLY:
		ret = of_fpga_region_notify_pre_apply(region, nd);
		break;

	case OF_OVERLAY_POST_REMOVE:
		of_fpga_region_notify_post_remove(region, nd);
		break;
	}

	put_device(&region->dev);

	if (ret)
		return notifier_from_errno(ret);

	return NOTIFY_OK;
}

static struct notifier_block fpga_region_of_nb = {
	.notifier_call = of_fpga_region_notify,
};

static int of_fpga_region_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct device_node *np = dev->of_node;
	struct fpga_region *region;
	struct fpga_manager *mgr;
	int ret;

	/* Find the FPGA mgr specified by region or parent region. */
	mgr = of_fpga_region_get_mgr(np);
	if (IS_ERR(mgr))
		return -EPROBE_DEFER;

	region = fpga_region_create(dev, mgr, of_fpga_region_get_bridges);
	if (!region) {
		ret = -ENOMEM;
		goto eprobe_mgr_put;
	}

	ret = fpga_region_register(region);
	if (ret)
		goto eprobe_free;

	of_platform_populate(np, fpga_region_of_match, NULL, &region->dev);
	dev_set_drvdata(dev, region);

	dev_info(dev, "FPGA Region probed\n");

	return 0;

eprobe_free:
	fpga_region_free(region);
eprobe_mgr_put:
	fpga_mgr_put(mgr);
	return ret;
}

static int of_fpga_region_remove(struct platform_device *pdev)
{
	struct fpga_region *region = platform_get_drvdata(pdev);

	fpga_region_unregister(region);
	fpga_mgr_put(region->mgr);

	return 0;
}

static struct platform_driver of_fpga_region_driver = {
	.probe = of_fpga_region_probe,
	.remove = of_fpga_region_remove,
	.driver = {
		.name	= "of-fpga-region",
		.of_match_table = of_match_ptr(fpga_region_of_match),
	},
};

/**
 * fpga_region_init - init function for fpga_region class
 * Creates the fpga_region class and registers a reconfig notifier.
 */
static int __init of_fpga_region_init(void)
{
	int ret;

	ret = of_overlay_notifier_register(&fpga_region_of_nb);
	if (ret)
		return ret;

	ret = platform_driver_register(&of_fpga_region_driver);
	if (ret)
		goto err_plat;

	return 0;

err_plat:
	of_overlay_notifier_unregister(&fpga_region_of_nb);
	return ret;
}

static void __exit of_fpga_region_exit(void)
{
	platform_driver_unregister(&of_fpga_region_driver);
	of_overlay_notifier_unregister(&fpga_region_of_nb);
}

subsys_initcall(of_fpga_region_init);
module_exit(of_fpga_region_exit);

MODULE_DESCRIPTION("FPGA Region");
MODULE_AUTHOR("Alan Tull <atull@kernel.org>");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
473f01f7	1	// SPDX-License-Identifier: GPL-2.0
ef3acdd8 AT	2	/*
	3	* FPGA Region - Device Tree support for FPGA programming under Linux
	4	*
	5	* Copyright (C) 2013-2016 Altera Corporation
	6	* Copyright (C) 2017 Intel Corporation
ef3acdd8	7	*/
ef3acdd8 AT	8	#include <linux/fpga/fpga-bridge.h>
	9	#include <linux/fpga/fpga-mgr.h>
	10	#include <linux/fpga/fpga-region.h>
	11	#include <linux/idr.h>
	12	#include <linux/kernel.h>
	13	#include <linux/list.h>
	14	#include <linux/module.h>
	15	#include <linux/of_platform.h>
	16	#include <linux/slab.h>
	17	#include <linux/spinlock.h>
	18
	19	static const struct of_device_id fpga_region_of_match[] = {
	20	{ .compatible = "fpga-region", },
	21	{},
	22	};
	23	MODULE_DEVICE_TABLE(of, fpga_region_of_match);
	24
	25	static int fpga_region_of_node_match(struct device dev, const void data)
	26	{
	27	return dev->of_node == data;
	28	}
	29
	30	/**
	31	* of_fpga_region_find - find FPGA region
	32	* @np: device node of FPGA Region
	33	*
	34	* Caller will need to put_device(&region->dev) when done.
	35	*
	36	* Returns FPGA Region struct or NULL
	37	*/
	38	static struct fpga_region of_fpga_region_find(struct device_node np)
	39	{
	40	return fpga_region_class_find(NULL, np, fpga_region_of_node_match);
	41	}
	42
	43	/**
	44	* of_fpga_region_get_mgr - get reference for FPGA manager
	45	* @np: device node of FPGA region
	46	*
	47	* Get FPGA Manager from "fpga-mgr" property or from ancestor region.
	48	*
	49	* Caller should call fpga_mgr_put() when done with manager.
	50	*
	51	* Return: fpga manager struct or IS_ERR() condition containing error code.
	52	*/
	53	static struct fpga_manager of_fpga_region_get_mgr(struct device_node np)
	54	{
	55	struct device_node *mgr_node;
	56	struct fpga_manager *mgr;
	57
	58	of_node_get(np);
	59	while (np) {
	60	if (of_device_is_compatible(np, "fpga-region")) {
	61	mgr_node = of_parse_phandle(np, "fpga-mgr", 0);
	62	if (mgr_node) {
	63	mgr = of_fpga_mgr_get(mgr_node);
0f5eb154	64	of_node_put(mgr_node);
ef3acdd8 AT	65	of_node_put(np);
	66	return mgr;
	67	}
	68	}
	69	np = of_get_next_parent(np);
	70	}
	71	of_node_put(np);
	72
	73	return ERR_PTR(-EINVAL);
	74	}
	75
	76	/**
	77	* of_fpga_region_get_bridges - create a list of bridges
	78	* @region: FPGA region
	79	*
	80	* Create a list of bridges including the parent bridge and the bridges
	81	* specified by "fpga-bridges" property. Note that the
	82	* fpga_bridges_enable/disable/put functions are all fine with an empty list
	83	* if that happens.
	84	*
	85	* Caller should call fpga_bridges_put(&region->bridge_list) when
	86	* done with the bridges.
	87	*
	88	* Return 0 for success (even if there are no bridges specified)
	89	* or -EBUSY if any of the bridges are in use.
	90	*/
	91	static int of_fpga_region_get_bridges(struct fpga_region *region)
	92	{
	93	struct device *dev = &region->dev;
	94	struct device_node *region_np = dev->of_node;
	95	struct fpga_image_info *info = region->info;
	96	struct device_node br, np, *parent_br = NULL;
	97	int i, ret;
	98
	99	/* If parent is a bridge, add to list */
	100	ret = of_fpga_bridge_get_to_list(region_np->parent, info,
	101	&region->bridge_list);
	102
	103	/* -EBUSY means parent is a bridge that is under use. Give up. */
	104	if (ret == -EBUSY)
	105	return ret;
	106
	107	/* Zero return code means parent was a bridge and was added to list. */
	108	if (!ret)
	109	parent_br = region_np->parent;
	110
	111	/* If overlay has a list of bridges, use it. */
0f5eb154 IA	112	br = of_parse_phandle(info->overlay, "fpga-bridges", 0);
	113	if (br) {
	114	of_node_put(br);
ef3acdd8	115	np = info->overlay;
0f5eb154	116	} else {
ef3acdd8	117	np = region_np;
0f5eb154	118	}
ef3acdd8 AT	119
	120	for (i = 0; ; i++) {
	121	br = of_parse_phandle(np, "fpga-bridges", i);
	122	if (!br)
	123	break;
	124
	125	/* If parent bridge is in list, skip it. */
0f5eb154 IA	126	if (br == parent_br) {
0f5eb154 IA	127	of_node_put(br);
ef3acdd8	128	continue;
0f5eb154	129	}
ef3acdd8 AT	130
	131	/* If node is a bridge, get it and add to list */
	132	ret = of_fpga_bridge_get_to_list(br, info,
	133	&region->bridge_list);
0f5eb154	134	of_node_put(br);
ef3acdd8 AT	135
	136	/* If any of the bridges are in use, give up */
	137	if (ret == -EBUSY) {
	138	fpga_bridges_put(&region->bridge_list);
	139	return -EBUSY;
	140	}
	141	}
	142
	143	return 0;
	144	}
	145
	146	/**
	147	* child_regions_with_firmware
	148	* @overlay: device node of the overlay
	149	*
	150	* If the overlay adds child FPGA regions, they are not allowed to have
	151	* firmware-name property.
	152	*
	153	* Return 0 for OK or -EINVAL if child FPGA region adds firmware-name.
	154	*/
	155	static int child_regions_with_firmware(struct device_node *overlay)
	156	{
	157	struct device_node *child_region;
	158	const char *child_firmware_name;
	159	int ret = 0;
	160
	161	of_node_get(overlay);
	162
	163	child_region = of_find_matching_node(overlay, fpga_region_of_match);
	164	while (child_region) {
	165	if (!of_property_read_string(child_region, "firmware-name",
	166	&child_firmware_name)) {
	167	ret = -EINVAL;
	168	break;
	169	}
	170	child_region = of_find_matching_node(child_region,
	171	fpga_region_of_match);
	172	}
	173
	174	of_node_put(child_region);
	175
	176	if (ret)
	177	pr_err("firmware-name not allowed in child FPGA region: %pOF",
	178	child_region);
	179
	180	return ret;
	181	}
	182
	183	/**
	184	* of_fpga_region_parse_ov - parse and check overlay applied to region
	185	*
	186	* @region: FPGA region
	187	* @overlay: overlay applied to the FPGA region
	188	*
	189	* Given an overlay applied to a FPGA region, parse the FPGA image specific
	190	* info in the overlay and do some checking.
	191	*
	192	* Returns:
	193	* NULL if overlay doesn't direct us to program the FPGA.
	194	* fpga_image_info struct if there is an image to program.
	195	* error code for invalid overlay.
	196	*/
	197	static struct fpga_image_info *of_fpga_region_parse_ov(
	198	struct fpga_region *region,
199	struct device_node *overlay)
200	{
201	struct device *dev = &region->dev;
202	struct fpga_image_info *info;
203	const char *firmware_name;
204	int ret;
205
206	if (region->info) {
207	dev_err(dev, "Region already has overlay applied.\n");
208	return ERR_PTR(-EINVAL);
209	}
210
211	/*
212	* Reject overlay if child FPGA Regions added in the overlay have
213	* firmware-name property (would mean that an FPGA region that has
214	* not been added to the live tree yet is doing FPGA programming).
215	*/
216	ret = child_regions_with_firmware(overlay);
217	if (ret)
218	return ERR_PTR(ret);
219
220	info = fpga_image_info_alloc(dev);
221	if (!info)
222	return ERR_PTR(-ENOMEM);
223
224	info->overlay = overlay;
225
226	/* Read FPGA region properties from the overlay */
227	if (of_property_read_bool(overlay, "partial-fpga-config"))
228	info->flags \|= FPGA_MGR_PARTIAL_RECONFIG;
229
230	if (of_property_read_bool(overlay, "external-fpga-config"))
231	info->flags \|= FPGA_MGR_EXTERNAL_CONFIG;
232
233	if (of_property_read_bool(overlay, "encrypted-fpga-config"))
234	info->flags \|= FPGA_MGR_ENCRYPTED_BITSTREAM;
235
236	if (!of_property_read_string(overlay, "firmware-name",
237	&firmware_name)) {
238	info->firmware_name = devm_kstrdup(dev, firmware_name,
239	GFP_KERNEL);
240	if (!info->firmware_name)
241	return ERR_PTR(-ENOMEM);
242	}
243
244	of_property_read_u32(overlay, "region-unfreeze-timeout-us",
245	&info->enable_timeout_us);
246
247	of_property_read_u32(overlay, "region-freeze-timeout-us",
248	&info->disable_timeout_us);
249
250	of_property_read_u32(overlay, "config-complete-timeout-us",
251	&info->config_complete_timeout_us);
252
253	/* If overlay is not programming the FPGA, don't need FPGA image info */
254	if (!info->firmware_name) {
255	ret = 0;
256	goto ret_no_info;
257	}
258
259	/*
260	* If overlay informs us FPGA was externally programmed, specifying
261	* firmware here would be ambiguous.
262	*/
263	if (info->flags & FPGA_MGR_EXTERNAL_CONFIG) {
264	dev_err(dev, "error: specified firmware and external-fpga-config");
265	ret = -EINVAL;
266	goto ret_no_info;
267	}
268
269	return info;
270	ret_no_info:
271	fpga_image_info_free(info);
272	return ERR_PTR(ret);
273	}
274
275	/**
276	* of_fpga_region_notify_pre_apply - pre-apply overlay notification
277	*
278	* @region: FPGA region that the overlay was applied to
279	* @nd: overlay notification data
280	*
281	* Called when an overlay targeted to a FPGA Region is about to be applied.
282	* Parses the overlay for properties that influence how the FPGA will be
283	* programmed and does some checking. If the checks pass, programs the FPGA.
284	* If the checks fail, overlay is rejected and does not get added to the
285	* live tree.
286	*
287	* Returns 0 for success or negative error code for failure.
288	*/
289	static int of_fpga_region_notify_pre_apply(struct fpga_region *region,
290	struct of_overlay_notify_data *nd)
291	{
292	struct device *dev = &region->dev;
293	struct fpga_image_info *info;
294	int ret;
295
ef3acdd8 AT	296	info = of_fpga_region_parse_ov(region, nd->overlay);
	297	if (IS_ERR(info))
	298	return PTR_ERR(info);
	299
8a541679	300	/* If overlay doesn't program the FPGA, accept it anyway. */
ef3acdd8 AT	301	if (!info)
	302	return 0;
	303
8a541679 AT	304	if (region->info) {
	305	dev_err(dev, "Region already has overlay applied.\n");
	306	return -EINVAL;
	307	}
	308
ef3acdd8 AT	309	region->info = info;
	310	ret = fpga_region_program_fpga(region);
	311	if (ret) {
	312	/* error; reject overlay */
	313	fpga_image_info_free(info);
	314	region->info = NULL;
	315	}
	316
	317	return ret;
	318	}
	319
	320	/**
	321	* of_fpga_region_notify_post_remove - post-remove overlay notification
	322	*
	323	* @region: FPGA region that was targeted by the overlay that was removed
	324	* @nd: overlay notification data
	325	*
	326	* Called after an overlay has been removed if the overlay's target was a
	327	* FPGA region.
	328	*/
	329	static void of_fpga_region_notify_post_remove(struct fpga_region *region,
	330	struct of_overlay_notify_data *nd)
	331	{
	332	fpga_bridges_disable(&region->bridge_list);
	333	fpga_bridges_put(&region->bridge_list);
	334	fpga_image_info_free(region->info);
	335	region->info = NULL;
	336	}
	337
	338	/**
	339	* of_fpga_region_notify - reconfig notifier for dynamic DT changes
	340	* @nb: notifier block
	341	* @action: notifier action
	342	* @arg: reconfig data
	343	*
	344	* This notifier handles programming a FPGA when a "firmware-name" property is
	345	* added to a fpga-region.
	346	*
	347	* Returns NOTIFY_OK or error if FPGA programming fails.
	348	*/
	349	static int of_fpga_region_notify(struct notifier_block *nb,
	350	unsigned long action, void *arg)
	351	{
	352	struct of_overlay_notify_data *nd = arg;
	353	struct fpga_region *region;
	354	int ret;
	355
	356	switch (action) {
	357	case OF_OVERLAY_PRE_APPLY:
	358	pr_debug("%s OF_OVERLAY_PRE_APPLY\n", __func__);
	359	break;
	360	case OF_OVERLAY_POST_APPLY:
	361	pr_debug("%s OF_OVERLAY_POST_APPLY\n", __func__);
	362	return NOTIFY_OK; /* not for us */
	363	case OF_OVERLAY_PRE_REMOVE:
	364	pr_debug("%s OF_OVERLAY_PRE_REMOVE\n", __func__);
	365	return NOTIFY_OK; /* not for us */
	366	case OF_OVERLAY_POST_REMOVE:
	367	pr_debug("%s OF_OVERLAY_POST_REMOVE\n", __func__);
	368	break;
	369	default: /* should not happen */
	370	return NOTIFY_OK;
	371	}
	372
373	region = of_fpga_region_find(nd->target);
374	if (!region)
375	return NOTIFY_OK;
376
377	ret = 0;
378	switch (action) {
379	case OF_OVERLAY_PRE_APPLY:
380	ret = of_fpga_region_notify_pre_apply(region, nd);
381	break;
382
383	case OF_OVERLAY_POST_REMOVE:
384	of_fpga_region_notify_post_remove(region, nd);
385	break;
386	}
387
388	put_device(&region->dev);
389
390	if (ret)
391	return notifier_from_errno(ret);
392
393	return NOTIFY_OK;
394	}
395
396	static struct notifier_block fpga_region_of_nb = {
397	.notifier_call = of_fpga_region_notify,
398	};
399
400	static int of_fpga_region_probe(struct platform_device *pdev)
401	{
402	struct device *dev = &pdev->dev;
403	struct device_node *np = dev->of_node;
404	struct fpga_region *region;
405	struct fpga_manager *mgr;
406	int ret;
407
408	/* Find the FPGA mgr specified by region or parent region. */
409	mgr = of_fpga_region_get_mgr(np);
410	if (IS_ERR(mgr))
411	return -EPROBE_DEFER;
412
9f368977	413	region = fpga_region_create(dev, mgr, of_fpga_region_get_bridges);
ef3acdd8 AT	414	if (!region) {
	415	ret = -ENOMEM;
	416	goto eprobe_mgr_put;
	417	}
	418
9f368977	419	ret = fpga_region_register(region);
ef3acdd8	420	if (ret)
9f368977	421	goto eprobe_free;
ef3acdd8 AT	422
ef3acdd8 AT	423	of_platform_populate(np, fpga_region_of_match, NULL, &region->dev);
bbaa9cd3	424	dev_set_drvdata(dev, region);
ef3acdd8 AT	425
	426	dev_info(dev, "FPGA Region probed\n");
	427
	428	return 0;
	429
9f368977 AT	430	eprobe_free:
9f368977 AT	431	fpga_region_free(region);
ef3acdd8 AT	432	eprobe_mgr_put:
	433	fpga_mgr_put(mgr);
	434	return ret;
	435	}
	436
	437	static int of_fpga_region_remove(struct platform_device *pdev)
	438	{
	439	struct fpga_region *region = platform_get_drvdata(pdev);
	440
	441	fpga_region_unregister(region);
	442	fpga_mgr_put(region->mgr);
	443
	444	return 0;
	445	}
	446
	447	static struct platform_driver of_fpga_region_driver = {
	448	.probe = of_fpga_region_probe,
	449	.remove = of_fpga_region_remove,
	450	.driver = {
	451	.name = "of-fpga-region",
	452	.of_match_table = of_match_ptr(fpga_region_of_match),
	453	},
	454	};
	455
	456	/**
	457	* fpga_region_init - init function for fpga_region class
	458	* Creates the fpga_region class and registers a reconfig notifier.
	459	*/
	460	static int __init of_fpga_region_init(void)
	461	{
	462	int ret;
	463
	464	ret = of_overlay_notifier_register(&fpga_region_of_nb);
	465	if (ret)
	466	return ret;
	467
	468	ret = platform_driver_register(&of_fpga_region_driver);
	469	if (ret)
	470	goto err_plat;
	471
	472	return 0;
	473
	474	err_plat:
	475	of_overlay_notifier_unregister(&fpga_region_of_nb);
	476	return ret;
	477	}
	478
	479	static void __exit of_fpga_region_exit(void)
	480	{
	481	platform_driver_unregister(&of_fpga_region_driver);
	482	of_overlay_notifier_unregister(&fpga_region_of_nb);
	483	}
	484
	485	subsys_initcall(of_fpga_region_init);
	486	module_exit(of_fpga_region_exit);
	487
	488	MODULE_DESCRIPTION("FPGA Region");
	489	MODULE_AUTHOR("Alan Tull <atull@kernel.org>");
	490	MODULE_LICENSE("GPL v2");