blob: f87b474d25a77f7ee4cb7224509e29bf65b423a9 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
#define pr_fmt(fmt) "papr-scm: " fmt
#include <linux/of.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/ioport.h>
#include <linux/slab.h>
#include <linux/ndctl.h>
#include <linux/sched.h>
#include <linux/libnvdimm.h>
#include <linux/platform_device.h>
#include <linux/delay.h>
#include <asm/plpar_wrappers.h>
#define BIND_ANY_ADDR (~0ul)
#define PAPR_SCM_DIMM_CMD_MASK \
((1ul << ND_CMD_GET_CONFIG_SIZE) | \
(1ul << ND_CMD_GET_CONFIG_DATA) | \
(1ul << ND_CMD_SET_CONFIG_DATA))
struct papr_scm_priv {
struct platform_device *pdev;
struct device_node *dn;
uint32_t drc_index;
uint64_t blocks;
uint64_t block_size;
int metadata_size;
bool is_volatile;
uint64_t bound_addr;
struct nvdimm_bus_descriptor bus_desc;
struct nvdimm_bus *bus;
struct nvdimm *nvdimm;
struct resource res;
struct nd_region *region;
struct nd_interleave_set nd_set;
};
static int drc_pmem_bind(struct papr_scm_priv *p)
{
unsigned long ret[PLPAR_HCALL_BUFSIZE];
uint64_t saved = 0;
uint64_t token;
int64_t rc;
/*
* When the hypervisor cannot map all the requested memory in a single
* hcall it returns H_BUSY and we call again with the token until
* we get H_SUCCESS. Aborting the retry loop before getting H_SUCCESS
* leave the system in an undefined state, so we wait.
*/
token = 0;
do {
rc = plpar_hcall(H_SCM_BIND_MEM, ret, p->drc_index, 0,
p->blocks, BIND_ANY_ADDR, token);
token = ret[0];
if (!saved)
saved = ret[1];
cond_resched();
} while (rc == H_BUSY);
if (rc)
return rc;
p->bound_addr = saved;
dev_dbg(&p->pdev->dev, "bound drc 0x%x to %pR\n", p->drc_index, &p->res);
return rc;
}
static void drc_pmem_unbind(struct papr_scm_priv *p)
{
unsigned long ret[PLPAR_HCALL_BUFSIZE];
uint64_t token = 0;
int64_t rc;
dev_dbg(&p->pdev->dev, "unbind drc 0x%x\n", p->drc_index);
/* NB: unbind has the same retry requirements as drc_pmem_bind() */
do {
/* Unbind of all SCM resources associated with drcIndex */
rc = plpar_hcall(H_SCM_UNBIND_ALL, ret, H_UNBIND_SCOPE_DRC,
p->drc_index, token);
token = ret[0];
/* Check if we are stalled for some time */
if (H_IS_LONG_BUSY(rc)) {
msleep(get_longbusy_msecs(rc));
rc = H_BUSY;
} else if (rc == H_BUSY) {
cond_resched();
}
} while (rc == H_BUSY);
if (rc)
dev_err(&p->pdev->dev, "unbind error: %lld\n", rc);
else
dev_dbg(&p->pdev->dev, "unbind drc 0x%x complete\n",
p->drc_index);
return;
}
static int drc_pmem_query_n_bind(struct papr_scm_priv *p)
{
unsigned long start_addr;
unsigned long end_addr;
unsigned long ret[PLPAR_HCALL_BUFSIZE];
int64_t rc;
rc = plpar_hcall(H_SCM_QUERY_BLOCK_MEM_BINDING, ret,
p->drc_index, 0);
if (rc)
goto err_out;
start_addr = ret[0];
/* Make sure the full region is bound. */
rc = plpar_hcall(H_SCM_QUERY_BLOCK_MEM_BINDING, ret,
p->drc_index, p->blocks - 1);
if (rc)
goto err_out;
end_addr = ret[0];
if ((end_addr - start_addr) != ((p->blocks - 1) * p->block_size))
goto err_out;
p->bound_addr = start_addr;
dev_dbg(&p->pdev->dev, "bound drc 0x%x to %pR\n", p->drc_index, &p->res);
return rc;
err_out:
dev_info(&p->pdev->dev,
"Failed to query, trying an unbind followed by bind");
drc_pmem_unbind(p);
return drc_pmem_bind(p);
}
static int papr_scm_meta_get(struct papr_scm_priv *p,
struct nd_cmd_get_config_data_hdr *hdr)
{
unsigned long data[PLPAR_HCALL_BUFSIZE];
unsigned long offset, data_offset;
int len, read;
int64_t ret;
if ((hdr->in_offset + hdr->in_length) > p->metadata_size)
return -EINVAL;
for (len = hdr->in_length; len; len -= read) {
data_offset = hdr->in_length - len;
offset = hdr->in_offset + data_offset;
if (len >= 8)
read = 8;
else if (len >= 4)
read = 4;
else if (len >= 2)
read = 2;
else
read = 1;
ret = plpar_hcall(H_SCM_READ_METADATA, data, p->drc_index,
offset, read);
if (ret == H_PARAMETER) /* bad DRC index */
return -ENODEV;
if (ret)
return -EINVAL; /* other invalid parameter */
switch (read) {
case 8:
*(uint64_t *)(hdr->out_buf + data_offset) = be64_to_cpu(data[0]);
break;
case 4:
*(uint32_t *)(hdr->out_buf + data_offset) = be32_to_cpu(data[0] & 0xffffffff);
break;
case 2:
*(uint16_t *)(hdr->out_buf + data_offset) = be16_to_cpu(data[0] & 0xffff);
break;
case 1:
*(uint8_t *)(hdr->out_buf + data_offset) = (data[0] & 0xff);
break;
}
}
return 0;
}
static int papr_scm_meta_set(struct papr_scm_priv *p,
struct nd_cmd_set_config_hdr *hdr)
{
unsigned long offset, data_offset;
int len, wrote;
unsigned long data;
__be64 data_be;
int64_t ret;
if ((hdr->in_offset + hdr->in_length) > p->metadata_size)
return -EINVAL;
for (len = hdr->in_length; len; len -= wrote) {
data_offset = hdr->in_length - len;
offset = hdr->in_offset + data_offset;
if (len >= 8) {
data = *(uint64_t *)(hdr->in_buf + data_offset);
data_be = cpu_to_be64(data);
wrote = 8;
} else if (len >= 4) {
data = *(uint32_t *)(hdr->in_buf + data_offset);
data &= 0xffffffff;
data_be = cpu_to_be32(data);
wrote = 4;
} else if (len >= 2) {
data = *(uint16_t *)(hdr->in_buf + data_offset);
data &= 0xffff;
data_be = cpu_to_be16(data);
wrote = 2;
} else {
data_be = *(uint8_t *)(hdr->in_buf + data_offset);
data_be &= 0xff;
wrote = 1;
}
ret = plpar_hcall_norets(H_SCM_WRITE_METADATA, p->drc_index,
offset, data_be, wrote);
if (ret == H_PARAMETER) /* bad DRC index */
return -ENODEV;
if (ret)
return -EINVAL; /* other invalid parameter */
}
return 0;
}
int papr_scm_ndctl(struct nvdimm_bus_descriptor *nd_desc, struct nvdimm *nvdimm,
unsigned int cmd, void *buf, unsigned int buf_len, int *cmd_rc)
{
struct nd_cmd_get_config_size *get_size_hdr;
struct papr_scm_priv *p;
/* Only dimm-specific calls are supported atm */
if (!nvdimm)
return -EINVAL;
p = nvdimm_provider_data(nvdimm);
switch (cmd) {
case ND_CMD_GET_CONFIG_SIZE:
get_size_hdr = buf;
get_size_hdr->status = 0;
get_size_hdr->max_xfer = 8;
get_size_hdr->config_size = p->metadata_size;
*cmd_rc = 0;
break;
case ND_CMD_GET_CONFIG_DATA:
*cmd_rc = papr_scm_meta_get(p, buf);
break;
case ND_CMD_SET_CONFIG_DATA:
*cmd_rc = papr_scm_meta_set(p, buf);
break;
default:
return -EINVAL;
}
dev_dbg(&p->pdev->dev, "returned with cmd_rc = %d\n", *cmd_rc);
return 0;
}
static const struct attribute_group *region_attr_groups[] = {
&nd_region_attribute_group,
&nd_device_attribute_group,
&nd_mapping_attribute_group,
&nd_numa_attribute_group,
NULL,
};
static const struct attribute_group *bus_attr_groups[] = {
&nvdimm_bus_attribute_group,
NULL,
};
static const struct attribute_group *papr_scm_dimm_groups[] = {
&nvdimm_attribute_group,
&nd_device_attribute_group,
NULL,
};
static inline int papr_scm_node(int node)
{
int min_dist = INT_MAX, dist;
int nid, min_node;
if ((node == NUMA_NO_NODE) || node_online(node))
return node;
min_node = first_online_node;
for_each_online_node(nid) {
dist = node_distance(node, nid);
if (dist < min_dist) {
min_dist = dist;
min_node = nid;
}
}
return min_node;
}
static int papr_scm_nvdimm_init(struct papr_scm_priv *p)
{
struct device *dev = &p->pdev->dev;
struct nd_mapping_desc mapping;
struct nd_region_desc ndr_desc;
unsigned long dimm_flags;
int target_nid, online_nid;
p->bus_desc.ndctl = papr_scm_ndctl;
p->bus_desc.module = THIS_MODULE;
p->bus_desc.of_node = p->pdev->dev.of_node;
p->bus_desc.attr_groups = bus_attr_groups;
p->bus_desc.provider_name = kstrdup(p->pdev->name, GFP_KERNEL);
if (!p->bus_desc.provider_name)
return -ENOMEM;
p->bus = nvdimm_bus_register(NULL, &p->bus_desc);
if (!p->bus) {
dev_err(dev, "Error creating nvdimm bus %pOF\n", p->dn);
return -ENXIO;
}
dimm_flags = 0;
set_bit(NDD_ALIASING, &dimm_flags);
p->nvdimm = nvdimm_create(p->bus, p, papr_scm_dimm_groups,
dimm_flags, PAPR_SCM_DIMM_CMD_MASK, 0, NULL);
if (!p->nvdimm) {
dev_err(dev, "Error creating DIMM object for %pOF\n", p->dn);
goto err;
}
if (nvdimm_bus_check_dimm_count(p->bus, 1))
goto err;
/* now add the region */
memset(&mapping, 0, sizeof(mapping));
mapping.nvdimm = p->nvdimm;
mapping.start = 0;
mapping.size = p->blocks * p->block_size; // XXX: potential overflow?
memset(&ndr_desc, 0, sizeof(ndr_desc));
ndr_desc.attr_groups = region_attr_groups;
target_nid = dev_to_node(&p->pdev->dev);
online_nid = papr_scm_node(target_nid);
ndr_desc.numa_node = online_nid;
ndr_desc.target_node = target_nid;
ndr_desc.res = &p->res;
ndr_desc.of_node = p->dn;
ndr_desc.provider_data = p;
ndr_desc.mapping = &mapping;
ndr_desc.num_mappings = 1;
ndr_desc.nd_set = &p->nd_set;
set_bit(ND_REGION_PAGEMAP, &ndr_desc.flags);
if (p->is_volatile)
p->region = nvdimm_volatile_region_create(p->bus, &ndr_desc);
else
p->region = nvdimm_pmem_region_create(p->bus, &ndr_desc);
if (!p->region) {
dev_err(dev, "Error registering region %pR from %pOF\n",
ndr_desc.res, p->dn);
goto err;
}
if (target_nid != online_nid)
dev_info(dev, "Region registered with target node %d and online node %d",
target_nid, online_nid);
return 0;
err: nvdimm_bus_unregister(p->bus);
kfree(p->bus_desc.provider_name);
return -ENXIO;
}
static int papr_scm_probe(struct platform_device *pdev)
{
struct device_node *dn = pdev->dev.of_node;
u32 drc_index, metadata_size;
u64 blocks, block_size;
struct papr_scm_priv *p;
const char *uuid_str;
u64 uuid[2];
int rc;
/* check we have all the required DT properties */
if (of_property_read_u32(dn, "ibm,my-drc-index", &drc_index)) {
dev_err(&pdev->dev, "%pOF: missing drc-index!\n", dn);
return -ENODEV;
}
if (of_property_read_u64(dn, "ibm,block-size", &block_size)) {
dev_err(&pdev->dev, "%pOF: missing block-size!\n", dn);
return -ENODEV;
}
if (of_property_read_u64(dn, "ibm,number-of-blocks", &blocks)) {
dev_err(&pdev->dev, "%pOF: missing number-of-blocks!\n", dn);
return -ENODEV;
}
if (of_property_read_string(dn, "ibm,unit-guid", &uuid_str)) {
dev_err(&pdev->dev, "%pOF: missing unit-guid!\n", dn);
return -ENODEV;
}
p = kzalloc(sizeof(*p), GFP_KERNEL);
if (!p)
return -ENOMEM;
/* optional DT properties */
of_property_read_u32(dn, "ibm,metadata-size", &metadata_size);
p->dn = dn;
p->drc_index = drc_index;
p->block_size = block_size;
p->blocks = blocks;
p->is_volatile = !of_property_read_bool(dn, "ibm,cache-flush-required");
/* We just need to ensure that set cookies are unique across */
uuid_parse(uuid_str, (uuid_t *) uuid);
/*
* cookie1 and cookie2 are not really little endian
* we store a little endian representation of the
* uuid str so that we can compare this with the label
* area cookie irrespective of the endian config with which
* the kernel is built.
*/
p->nd_set.cookie1 = cpu_to_le64(uuid[0]);
p->nd_set.cookie2 = cpu_to_le64(uuid[1]);
/* might be zero */
p->metadata_size = metadata_size;
p->pdev = pdev;
/* request the hypervisor to bind this region to somewhere in memory */
rc = drc_pmem_bind(p);
/* If phyp says drc memory still bound then force unbound and retry */
if (rc == H_OVERLAP)
rc = drc_pmem_query_n_bind(p);
if (rc != H_SUCCESS) {
dev_err(&p->pdev->dev, "bind err: %d\n", rc);
rc = -ENXIO;
goto err;
}
/* setup the resource for the newly bound range */
p->res.start = p->bound_addr;
p->res.end = p->bound_addr + p->blocks * p->block_size - 1;
p->res.name = pdev->name;
p->res.flags = IORESOURCE_MEM;
rc = papr_scm_nvdimm_init(p);
if (rc)
goto err2;
platform_set_drvdata(pdev, p);
return 0;
err2: drc_pmem_unbind(p);
err: kfree(p);
return rc;
}
static int papr_scm_remove(struct platform_device *pdev)
{
struct papr_scm_priv *p = platform_get_drvdata(pdev);
nvdimm_bus_unregister(p->bus);
drc_pmem_unbind(p);
kfree(p);
return 0;
}
static const struct of_device_id papr_scm_match[] = {
{ .compatible = "ibm,pmemory" },
{ },
};
static struct platform_driver papr_scm_driver = {
.probe = papr_scm_probe,
.remove = papr_scm_remove,
.driver = {
.name = "papr_scm",
.of_match_table = papr_scm_match,
},
};
module_platform_driver(papr_scm_driver);
MODULE_DEVICE_TABLE(of, papr_scm_match);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("IBM Corporation");