1// SPDX-License-Identifier: GPL-2.0+
  2
  3#define pr_fmt(fmt) "of_pmem: " fmt
  4
  5#include <linux/of.h>
  6#include <linux/libnvdimm.h>
  7#include <linux/module.h>
  8#include <linux/ioport.h>
  9#include <linux/platform_device.h>
 10#include <linux/slab.h>
 11
 12struct of_pmem_private {
 13	struct nvdimm_bus_descriptor bus_desc;
 14	struct nvdimm_bus *bus;
 15};
 16
 17static int of_pmem_region_probe(struct platform_device *pdev)
 18{
 19	struct of_pmem_private *priv;
 20	struct device_node *np;
 21	struct nvdimm_bus *bus;
 22	bool is_volatile;
 23	int i;
 24
 25	np = dev_of_node(&pdev->dev);
 26	if (!np)
 27		return -ENXIO;
 28
 29	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
 30	if (!priv)
 31		return -ENOMEM;
 32
 33	priv->bus_desc.provider_name = devm_kstrdup(&pdev->dev, pdev->name,
 34							GFP_KERNEL);
 35	if (!priv->bus_desc.provider_name) {
 36		kfree(priv);
 37		return -ENOMEM;
 38	}
 39
 40	priv->bus_desc.module = THIS_MODULE;
 41	priv->bus_desc.of_node = np;
 42
 43	priv->bus = bus = nvdimm_bus_register(&pdev->dev, &priv->bus_desc);
 44	if (!bus) {
 45		kfree(priv);
 46		return -ENODEV;
 47	}
 48	platform_set_drvdata(pdev, priv);
 49
 50	is_volatile = !!of_find_property(np, "volatile", NULL);
 51	dev_dbg(&pdev->dev, "Registering %s regions from %pOF\n",
 52			is_volatile ? "volatile" : "non-volatile",  np);
 53
 54	for (i = 0; i < pdev->num_resources; i++) {
 55		struct nd_region_desc ndr_desc;
 56		struct nd_region *region;
 57
 58		/*
 59		 * NB: libnvdimm copies the data from ndr_desc into it's own
 60		 * structures so passing a stack pointer is fine.
 61		 */
 62		memset(&ndr_desc, 0, sizeof(ndr_desc));
 63		ndr_desc.numa_node = dev_to_node(&pdev->dev);
 64		ndr_desc.target_node = ndr_desc.numa_node;
 65		ndr_desc.res = &pdev->resource[i];
 66		ndr_desc.of_node = np;
 67		set_bit(ND_REGION_PAGEMAP, &ndr_desc.flags);
 68
 69		if (is_volatile)
 70			region = nvdimm_volatile_region_create(bus, &ndr_desc);
 71		else {
 72			set_bit(ND_REGION_PERSIST_MEMCTRL, &ndr_desc.flags);
 73			region = nvdimm_pmem_region_create(bus, &ndr_desc);
 74		}
 75
 76		if (!region)
 77			dev_warn(&pdev->dev, "Unable to register region %pR from %pOF\n",
 78					ndr_desc.res, np);
 79		else
 80			dev_dbg(&pdev->dev, "Registered region %pR from %pOF\n",
 81					ndr_desc.res, np);
 82	}
 83
 84	return 0;
 85}
 86
 87static int of_pmem_region_remove(struct platform_device *pdev)
 88{
 89	struct of_pmem_private *priv = platform_get_drvdata(pdev);
 90
 91	nvdimm_bus_unregister(priv->bus);
 92	kfree(priv);
 93
 94	return 0;
 95}
 96
 97static const struct of_device_id of_pmem_region_match[] = {
 98	{ .compatible = "pmem-region" },
 99	{ .compatible = "pmem-region-v2" },
100	{ },
101};
102
103static struct platform_driver of_pmem_region_driver = {
104	.probe = of_pmem_region_probe,
105	.remove = of_pmem_region_remove,
106	.driver = {
107		.name = "of_pmem",
108		.of_match_table = of_pmem_region_match,
109	},
110};
111
112module_platform_driver(of_pmem_region_driver);
113MODULE_DEVICE_TABLE(of, of_pmem_region_match);
114MODULE_LICENSE("GPL");
115MODULE_AUTHOR("IBM Corporation");