libnvdimm: Add device-tree based driver

This patch adds peliminary device-tree bindings for persistent memory
regions. The driver registers a libnvdimm bus for each pmem-region
node and each address range under the node is converted to a region
within that bus.

Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This commit is contained in:
Oliver O'Halloran 2018-04-06 15:21:14 +10:00 committed by Dan Williams
parent 1ff19f487a
commit 7171976089
4 changed files with 137 additions and 0 deletions

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@ -8035,6 +8035,13 @@ Q: https://patchwork.kernel.org/project/linux-nvdimm/list/
S: Supported
F: drivers/nvdimm/pmem*
LIBNVDIMM: DEVICETREE BINDINGS
M: Oliver O'Halloran <oohall@gmail.com>
L: linux-nvdimm@lists.01.org
Q: https://patchwork.kernel.org/project/linux-nvdimm/list/
S: Supported
F: drivers/nvdimm/of_pmem.c
LIBNVDIMM: NON-VOLATILE MEMORY DEVICE SUBSYSTEM
M: Dan Williams <dan.j.williams@intel.com>
L: linux-nvdimm@lists.01.org

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@ -102,4 +102,14 @@ config NVDIMM_DAX
Select Y if unsure
config OF_PMEM
tristate "Device-tree support for persistent memory regions"
depends on OF
default LIBNVDIMM
help
Allows regions of persistent memory to be described in the
device-tree.
Select Y if unsure.
endif

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@ -4,6 +4,7 @@ obj-$(CONFIG_BLK_DEV_PMEM) += nd_pmem.o
obj-$(CONFIG_ND_BTT) += nd_btt.o
obj-$(CONFIG_ND_BLK) += nd_blk.o
obj-$(CONFIG_X86_PMEM_LEGACY) += nd_e820.o
obj-$(CONFIG_OF_PMEM) += of_pmem.o
nd_pmem-y := pmem.o

119
drivers/nvdimm/of_pmem.c Normal file
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@ -0,0 +1,119 @@
// SPDX-License-Identifier: GPL-2.0+
#define pr_fmt(fmt) "of_pmem: " fmt
#include <linux/of_platform.h>
#include <linux/of_address.h>
#include <linux/libnvdimm.h>
#include <linux/module.h>
#include <linux/ioport.h>
#include <linux/slab.h>
static const struct attribute_group *region_attr_groups[] = {
&nd_region_attribute_group,
&nd_device_attribute_group,
NULL,
};
static const struct attribute_group *bus_attr_groups[] = {
&nvdimm_bus_attribute_group,
NULL,
};
struct of_pmem_private {
struct nvdimm_bus_descriptor bus_desc;
struct nvdimm_bus *bus;
};
static int of_pmem_region_probe(struct platform_device *pdev)
{
struct of_pmem_private *priv;
struct device_node *np;
struct nvdimm_bus *bus;
bool is_volatile;
int i;
np = dev_of_node(&pdev->dev);
if (!np)
return -ENXIO;
priv = kzalloc(sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
priv->bus_desc.attr_groups = bus_attr_groups;
priv->bus_desc.provider_name = "of_pmem";
priv->bus_desc.module = THIS_MODULE;
priv->bus_desc.of_node = np;
priv->bus = bus = nvdimm_bus_register(&pdev->dev, &priv->bus_desc);
if (!bus) {
kfree(priv);
return -ENODEV;
}
platform_set_drvdata(pdev, priv);
is_volatile = !!of_find_property(np, "volatile", NULL);
dev_dbg(&pdev->dev, "Registering %s regions from %pOF\n",
is_volatile ? "volatile" : "non-volatile", np);
for (i = 0; i < pdev->num_resources; i++) {
struct nd_region_desc ndr_desc;
struct nd_region *region;
/*
* NB: libnvdimm copies the data from ndr_desc into it's own
* structures so passing a stack pointer is fine.
*/
memset(&ndr_desc, 0, sizeof(ndr_desc));
ndr_desc.attr_groups = region_attr_groups;
ndr_desc.numa_node = of_node_to_nid(np);
ndr_desc.res = &pdev->resource[i];
ndr_desc.of_node = np;
set_bit(ND_REGION_PAGEMAP, &ndr_desc.flags);
if (is_volatile)
region = nvdimm_volatile_region_create(bus, &ndr_desc);
else
region = nvdimm_pmem_region_create(bus, &ndr_desc);
if (!region)
dev_warn(&pdev->dev, "Unable to register region %pR from %pOF\n",
ndr_desc.res, np);
else
dev_dbg(&pdev->dev, "Registered region %pR from %pOF\n",
ndr_desc.res, np);
}
return 0;
}
static int of_pmem_region_remove(struct platform_device *pdev)
{
struct of_pmem_private *priv = platform_get_drvdata(pdev);
nvdimm_bus_unregister(priv->bus);
kfree(priv);
return 0;
}
static const struct of_device_id of_pmem_region_match[] = {
{ .compatible = "pmem-region" },
{ },
};
static struct platform_driver of_pmem_region_driver = {
.probe = of_pmem_region_probe,
.remove = of_pmem_region_remove,
.driver = {
.name = "of_pmem",
.owner = THIS_MODULE,
.of_match_table = of_pmem_region_match,
},
};
module_platform_driver(of_pmem_region_driver);
MODULE_DEVICE_TABLE(of, of_pmem_region_match);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("IBM Corporation");