1// SPDX-License-Identifier: GPL-2.0+
  2
  3#define pr_fmt(fmt) "of_pmem: " fmt
  4
  5#include <linux/of_platform.h>
  6#include <linux/of_address.h>
  7#include <linux/libnvdimm.h>
  8#include <linux/module.h>
  9#include <linux/ioport.h>
 10#include <linux/slab.h>
 11
 12static const struct attribute_group *region_attr_groups[] = {
 13	&nd_region_attribute_group,
 14	&nd_device_attribute_group,
 15	NULL,
 16};
 17
 18static const struct attribute_group *bus_attr_groups[] = {
 19	&nvdimm_bus_attribute_group,
 20	NULL,
 21};
 22
 23struct of_pmem_private {
 24	struct nvdimm_bus_descriptor bus_desc;
 25	struct nvdimm_bus *bus;
 26};
 27
 28static int of_pmem_region_probe(struct platform_device *pdev)
 29{
 30	struct of_pmem_private *priv;
 31	struct device_node *np;
 32	struct nvdimm_bus *bus;
 33	bool is_volatile;
 34	int i;
 35
 36	np = dev_of_node(&pdev->dev);
 37	if (!np)
 38		return -ENXIO;
 39
 40	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
 41	if (!priv)
 42		return -ENOMEM;
 43
 44	priv->bus_desc.attr_groups = bus_attr_groups;
 45	priv->bus_desc.provider_name = "of_pmem";
 46	priv->bus_desc.module = THIS_MODULE;
 47	priv->bus_desc.of_node = np;
 48
 49	priv->bus = bus = nvdimm_bus_register(&pdev->dev, &priv->bus_desc);
 50	if (!bus) {
 51		kfree(priv);
 52		return -ENODEV;
 53	}
 54	platform_set_drvdata(pdev, priv);
 55
 56	is_volatile = !!of_find_property(np, "volatile", NULL);
 57	dev_dbg(&pdev->dev, "Registering %s regions from %pOF\n",
 58			is_volatile ? "volatile" : "non-volatile",  np);
 59
 60	for (i = 0; i < pdev->num_resources; i++) {
 61		struct nd_region_desc ndr_desc;
 62		struct nd_region *region;
 63
 64		/*
 65		 * NB: libnvdimm copies the data from ndr_desc into it's own
 66		 * structures so passing a stack pointer is fine.
 67		 */
 68		memset(&ndr_desc, 0, sizeof(ndr_desc));
 69		ndr_desc.attr_groups = region_attr_groups;
 70		ndr_desc.numa_node = dev_to_node(&pdev->dev);
 71		ndr_desc.res = &pdev->resource[i];
 72		ndr_desc.of_node = np;
 73		set_bit(ND_REGION_PAGEMAP, &ndr_desc.flags);
 74
 75		if (is_volatile)
 76			region = nvdimm_volatile_region_create(bus, &ndr_desc);
 77		else
 78			region = nvdimm_pmem_region_create(bus, &ndr_desc);
 79
 80		if (!region)
 81			dev_warn(&pdev->dev, "Unable to register region %pR from %pOF\n",
 82					ndr_desc.res, np);
 83		else
 84			dev_dbg(&pdev->dev, "Registered region %pR from %pOF\n",
 85					ndr_desc.res, np);
 86	}
 87
 88	return 0;
 89}
 90
 91static int of_pmem_region_remove(struct platform_device *pdev)
 92{
 93	struct of_pmem_private *priv = platform_get_drvdata(pdev);
 94
 95	nvdimm_bus_unregister(priv->bus);
 96	kfree(priv);
 97
 98	return 0;
 99}
100
101static const struct of_device_id of_pmem_region_match[] = {
102	{ .compatible = "pmem-region" },
103	{ },
104};
105
106static struct platform_driver of_pmem_region_driver = {
107	.probe = of_pmem_region_probe,
108	.remove = of_pmem_region_remove,
109	.driver = {
110		.name = "of_pmem",
111		.owner = THIS_MODULE,
112		.of_match_table = of_pmem_region_match,
113	},
114};
115
116module_platform_driver(of_pmem_region_driver);
117MODULE_DEVICE_TABLE(of, of_pmem_region_match);
118MODULE_LICENSE("GPL");
119MODULE_AUTHOR("IBM Corporation");