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
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");
116