arch/powerpc/platforms/pseries/papr_scm.c

   1 // SPDX-License-Identifier: GPL-2.0
   2
   3 #define pr_fmt(fmt)     "papr-scm: " fmt
   4
   5 #include <linux/of.h>
   6 #include <linux/kernel.h>
   7 #include <linux/module.h>
   8 #include <linux/ioport.h>
   9 #include <linux/slab.h>
  10 #include <linux/ndctl.h>
  11 #include <linux/sched.h>
  12 #include <linux/libnvdimm.h>
  13 #include <linux/platform_device.h>
  14
  15 #include <asm/plpar_wrappers.h>
  16
  17 #define BIND_ANY_ADDR (~0ul)
  18
  19 #define PAPR_SCM_DIMM_CMD_MASK \
  20         ((1ul << ND_CMD_GET_CONFIG_SIZE) | \
  21          (1ul << ND_CMD_GET_CONFIG_DATA) | \
  22          (1ul << ND_CMD_SET_CONFIG_DATA))
  23
  24 struct papr_scm_priv {
  25         struct platform_device *pdev;
  26         struct device_node *dn;
  27         uint32_t drc_index;
  28         uint64_t blocks;
  29         uint64_t block_size;
  30         int metadata_size;
  31         bool is_volatile;
  32
  33         uint64_t bound_addr;
  34
  35         struct nvdimm_bus_descriptor bus_desc;
  36         struct nvdimm_bus *bus;
  37         struct nvdimm *nvdimm;
  38         struct resource res;
  39         struct nd_region *region;
  40         struct nd_interleave_set nd_set;
  41 };
  42
  43 static int drc_pmem_bind(struct papr_scm_priv *p)
  44 {
  45         unsigned long ret[PLPAR_HCALL_BUFSIZE];
  46         uint64_t rc, token;
  47         uint64_t saved = 0;
  48
  49         /*
  50          * When the hypervisor cannot map all the requested memory in a single
  51          * hcall it returns H_BUSY and we call again with the token until
  52          * we get H_SUCCESS. Aborting the retry loop before getting H_SUCCESS
  53          * leave the system in an undefined state, so we wait.
  54          */
  55         token = 0;
  56
  57         do {
  58                 rc = plpar_hcall(H_SCM_BIND_MEM, ret, p->drc_index, 0,
  59                                 p->blocks, BIND_ANY_ADDR, token);
  60                 token = ret[0];
  61                 if (!saved)
  62                         saved = ret[1];
  63                 cond_resched();
  64         } while (rc == H_BUSY);
  65
  66         if (rc) {
  67                 dev_err(&p->pdev->dev, "bind err: %lld\n", rc);
  68                 return -ENXIO;
  69         }
  70
  71         p->bound_addr = saved;
  72
  73         dev_dbg(&p->pdev->dev, "bound drc %x to %pR\n", p->drc_index, &p->res);
  74
  75         return 0;
  76 }
  77
  78 static int drc_pmem_unbind(struct papr_scm_priv *p)
  79 {
  80         unsigned long ret[PLPAR_HCALL_BUFSIZE];
  81         uint64_t rc, token;
  82
  83         token = 0;
  84
  85         /* NB: unbind has the same retry requirements mentioned above */
  86         do {
  87                 rc = plpar_hcall(H_SCM_UNBIND_MEM, ret, p->drc_index,
  88                                 p->bound_addr, p->blocks, token);
  89                 token = ret[0];
  90                 cond_resched();
  91         } while (rc == H_BUSY);
  92
  93         if (rc)
  94                 dev_err(&p->pdev->dev, "unbind error: %lld\n", rc);
  95
  96         return !!rc;
  97 }
  98
  99 static int papr_scm_meta_get(struct papr_scm_priv *p,
 100                              struct nd_cmd_get_config_data_hdr *hdr)
 101 {
 102         unsigned long data[PLPAR_HCALL_BUFSIZE];
 103         unsigned long offset, data_offset;
 104         int len, read;
 105         int64_t ret;
 106
 107         if ((hdr->in_offset + hdr->in_length) >= p->metadata_size)
 108                 return -EINVAL;
 109
 110         for (len = hdr->in_length; len; len -= read) {
 111
 112                 data_offset = hdr->in_length - len;
 113                 offset = hdr->in_offset + data_offset;
 114
 115                 if (len >= 8)
 116                         read = 8;
 117                 else if (len >= 4)
 118                         read = 4;
 119                 else if (len >= 2)
 120                         read = 2;
 121                 else
 122                         read = 1;
 123
 124                 ret = plpar_hcall(H_SCM_READ_METADATA, data, p->drc_index,
 125                                   offset, read);
 126
 127                 if (ret == H_PARAMETER) /* bad DRC index */
 128                         return -ENODEV;
 129                 if (ret)
 130                         return -EINVAL; /* other invalid parameter */
 131
 132                 switch (read) {
 133                 case 8:
 134                         *(uint64_t *)(hdr->out_buf + data_offset) = be64_to_cpu(data[0]);
 135                         break;
 136                 case 4:
 137                         *(uint32_t *)(hdr->out_buf + data_offset) = be32_to_cpu(data[0] & 0xffffffff);
 138                         break;
 139
 140                 case 2:
 141                         *(uint16_t *)(hdr->out_buf + data_offset) = be16_to_cpu(data[0] & 0xffff);
 142                         break;
 143
 144                 case 1:
 145                         *(uint8_t *)(hdr->out_buf + data_offset) = (data[0] & 0xff);
 146                         break;
 147                 }
 148         }
 149         return 0;
 150 }
 151
 152 static int papr_scm_meta_set(struct papr_scm_priv *p,
 153                              struct nd_cmd_set_config_hdr *hdr)
 154 {
 155         unsigned long offset, data_offset;
 156         int len, wrote;
 157         unsigned long data;
 158         __be64 data_be;
 159         int64_t ret;
 160
 161         if ((hdr->in_offset + hdr->in_length) >= p->metadata_size)
 162                 return -EINVAL;
 163
 164         for (len = hdr->in_length; len; len -= wrote) {
 165
 166                 data_offset = hdr->in_length - len;
 167                 offset = hdr->in_offset + data_offset;
 168
 169                 if (len >= 8) {
 170                         data = *(uint64_t *)(hdr->in_buf + data_offset);
 171                         data_be = cpu_to_be64(data);
 172                         wrote = 8;
 173                 } else if (len >= 4) {
 174                         data = *(uint32_t *)(hdr->in_buf + data_offset);
 175                         data &= 0xffffffff;
 176                         data_be = cpu_to_be32(data);
 177                         wrote = 4;
 178                 } else if (len >= 2) {
 179                         data = *(uint16_t *)(hdr->in_buf + data_offset);
 180                         data &= 0xffff;
 181                         data_be = cpu_to_be16(data);
 182                         wrote = 2;
 183                 } else {
 184                         data_be = *(uint8_t *)(hdr->in_buf + data_offset);
 185                         data_be &= 0xff;
 186                         wrote = 1;
 187                 }
 188
 189                 ret = plpar_hcall_norets(H_SCM_WRITE_METADATA, p->drc_index,
 190                                          offset, data_be, wrote);
 191                 if (ret == H_PARAMETER) /* bad DRC index */
 192                         return -ENODEV;
 193                 if (ret)
 194                         return -EINVAL; /* other invalid parameter */
 195         }
 196
 197         return 0;
 198 }
 199
 200 int papr_scm_ndctl(struct nvdimm_bus_descriptor *nd_desc, struct nvdimm *nvdimm,
 201                 unsigned int cmd, void *buf, unsigned int buf_len, int *cmd_rc)
 202 {
 203         struct nd_cmd_get_config_size *get_size_hdr;
 204         struct papr_scm_priv *p;
 205
 206         /* Only dimm-specific calls are supported atm */
 207         if (!nvdimm)
 208                 return -EINVAL;
 209
 210         p = nvdimm_provider_data(nvdimm);
 211
 212         switch (cmd) {
 213         case ND_CMD_GET_CONFIG_SIZE:
 214                 get_size_hdr = buf;
 215
 216                 get_size_hdr->status = 0;
 217                 get_size_hdr->max_xfer = 8;
 218                 get_size_hdr->config_size = p->metadata_size;
 219                 *cmd_rc = 0;
 220                 break;
 221
 222         case ND_CMD_GET_CONFIG_DATA:
 223                 *cmd_rc = papr_scm_meta_get(p, buf);
 224                 break;
 225
 226         case ND_CMD_SET_CONFIG_DATA:
 227                 *cmd_rc = papr_scm_meta_set(p, buf);
 228                 break;
 229
 230         default:
 231                 return -EINVAL;
 232         }
 233
 234         dev_dbg(&p->pdev->dev, "returned with cmd_rc = %d\n", *cmd_rc);
 235
 236         return 0;
 237 }
 238
 239 static const struct attribute_group *region_attr_groups[] = {
 240         &nd_region_attribute_group,
 241         &nd_device_attribute_group,
 242         &nd_mapping_attribute_group,
 243         &nd_numa_attribute_group,
 244         NULL,
 245 };
 246
 247 static const struct attribute_group *bus_attr_groups[] = {
 248         &nvdimm_bus_attribute_group,
 249         NULL,
 250 };
 251
 252 static const struct attribute_group *papr_scm_dimm_groups[] = {
 253         &nvdimm_attribute_group,
 254         &nd_device_attribute_group,
 255         NULL,
 256 };
 257
 258 static int papr_scm_nvdimm_init(struct papr_scm_priv *p)
 259 {
 260         struct device *dev = &p->pdev->dev;
 261         struct nd_mapping_desc mapping;
 262         struct nd_region_desc ndr_desc;
 263         unsigned long dimm_flags;
 264
 265         p->bus_desc.ndctl = papr_scm_ndctl;
 266         p->bus_desc.module = THIS_MODULE;
 267         p->bus_desc.of_node = p->pdev->dev.of_node;
 268         p->bus_desc.attr_groups = bus_attr_groups;
 269         p->bus_desc.provider_name = kstrdup(p->pdev->name, GFP_KERNEL);
 270
 271         if (!p->bus_desc.provider_name)
 272                 return -ENOMEM;
 273
 274         p->bus = nvdimm_bus_register(NULL, &p->bus_desc);
 275         if (!p->bus) {
 276                 dev_err(dev, "Error creating nvdimm bus %pOF\n", p->dn);
 277                 return -ENXIO;
 278         }
 279
 280         dimm_flags = 0;
 281         set_bit(NDD_ALIASING, &dimm_flags);
 282
 283         p->nvdimm = nvdimm_create(p->bus, p, papr_scm_dimm_groups,
 284                                 dimm_flags, PAPR_SCM_DIMM_CMD_MASK, 0, NULL);
 285         if (!p->nvdimm) {
 286                 dev_err(dev, "Error creating DIMM object for %pOF\n", p->dn);
 287                 goto err;
 288         }
 289
 290         if (nvdimm_bus_check_dimm_count(p->bus, 1))
 291                 goto err;
 292
 293         /* now add the region */
 294
 295         memset(&mapping, 0, sizeof(mapping));
 296         mapping.nvdimm = p->nvdimm;
 297         mapping.start = 0;
 298         mapping.size = p->blocks * p->block_size; // XXX: potential overflow?
 299
 300         memset(&ndr_desc, 0, sizeof(ndr_desc));
 301         ndr_desc.attr_groups = region_attr_groups;
 302         ndr_desc.numa_node = dev_to_node(&p->pdev->dev);
 303         ndr_desc.target_node = ndr_desc.numa_node;
 304         ndr_desc.res = &p->res;
 305         ndr_desc.of_node = p->dn;
 306         ndr_desc.provider_data = p;
 307         ndr_desc.mapping = &mapping;
 308         ndr_desc.num_mappings = 1;
 309         ndr_desc.nd_set = &p->nd_set;
 310         set_bit(ND_REGION_PAGEMAP, &ndr_desc.flags);
 311
 312         if (p->is_volatile)
 313                 p->region = nvdimm_volatile_region_create(p->bus, &ndr_desc);
 314         else
 315                 p->region = nvdimm_pmem_region_create(p->bus, &ndr_desc);
 316         if (!p->region) {
 317                 dev_err(dev, "Error registering region %pR from %pOF\n",
 318                                 ndr_desc.res, p->dn);
 319                 goto err;
 320         }
 321
 322         return 0;
 323
 324 err:    nvdimm_bus_unregister(p->bus);
 325         kfree(p->bus_desc.provider_name);
 326         return -ENXIO;
 327 }
 328
 329 static int papr_scm_probe(struct platform_device *pdev)
 330 {
 331         struct device_node *dn = pdev->dev.of_node;
 332         u32 drc_index, metadata_size;
 333         u64 blocks, block_size;
 334         struct papr_scm_priv *p;
 335         const char *uuid_str;
 336         u64 uuid[2];
 337         int rc;
 338
 339         /* check we have all the required DT properties */
 340         if (of_property_read_u32(dn, "ibm,my-drc-index", &drc_index)) {
 341                 dev_err(&pdev->dev, "%pOF: missing drc-index!\n", dn);
 342                 return -ENODEV;
 343         }
 344
 345         if (of_property_read_u64(dn, "ibm,block-size", &block_size)) {
 346                 dev_err(&pdev->dev, "%pOF: missing block-size!\n", dn);
 347                 return -ENODEV;
 348         }
 349
 350         if (of_property_read_u64(dn, "ibm,number-of-blocks", &blocks)) {
 351                 dev_err(&pdev->dev, "%pOF: missing number-of-blocks!\n", dn);
 352                 return -ENODEV;
 353         }
 354
 355         if (of_property_read_string(dn, "ibm,unit-guid", &uuid_str)) {
 356                 dev_err(&pdev->dev, "%pOF: missing unit-guid!\n", dn);
 357                 return -ENODEV;
 358         }
 359
 360
 361         p = kzalloc(sizeof(*p), GFP_KERNEL);
 362         if (!p)
 363                 return -ENOMEM;
 364
 365         /* optional DT properties */
 366         of_property_read_u32(dn, "ibm,metadata-size", &metadata_size);
 367
 368         p->dn = dn;
 369         p->drc_index = drc_index;
 370         p->block_size = block_size;
 371         p->blocks = blocks;
 372         p->is_volatile = !of_property_read_bool(dn, "ibm,cache-flush-required");
 373
 374         /* We just need to ensure that set cookies are unique across */
 375         uuid_parse(uuid_str, (uuid_t *) uuid);
 376         p->nd_set.cookie1 = uuid[0];
 377         p->nd_set.cookie2 = uuid[1];
 378
 379         /* might be zero */
 380         p->metadata_size = metadata_size;
 381         p->pdev = pdev;
 382
 383         /* request the hypervisor to bind this region to somewhere in memory */
 384         rc = drc_pmem_bind(p);
 385         if (rc)
 386                 goto err;
 387
 388         /* setup the resource for the newly bound range */
 389         p->res.start = p->bound_addr;
 390         p->res.end   = p->bound_addr + p->blocks * p->block_size - 1;
 391         p->res.name  = pdev->name;
 392         p->res.flags = IORESOURCE_MEM;
 393
 394         rc = papr_scm_nvdimm_init(p);
 395         if (rc)
 396                 goto err2;
 397
 398         platform_set_drvdata(pdev, p);
 399
 400         return 0;
 401
 402 err2:   drc_pmem_unbind(p);
 403 err:    kfree(p);
 404         return rc;
 405 }
 406
 407 static int papr_scm_remove(struct platform_device *pdev)
 408 {
 409         struct papr_scm_priv *p = platform_get_drvdata(pdev);
 410
 411         nvdimm_bus_unregister(p->bus);
 412         drc_pmem_unbind(p);
 413         kfree(p);
 414
 415         return 0;
 416 }
 417
 418 static const struct of_device_id papr_scm_match[] = {
 419         { .compatible = "ibm,pmemory" },
 420         { },
 421 };
 422
 423 static struct platform_driver papr_scm_driver = {
 424         .probe = papr_scm_probe,
 425         .remove = papr_scm_remove,
 426         .driver = {
 427                 .name = "papr_scm",
 428                 .owner = THIS_MODULE,
 429                 .of_match_table = papr_scm_match,
 430         },
 431 };
 432
 433 module_platform_driver(papr_scm_driver);
 434 MODULE_DEVICE_TABLE(of, papr_scm_match);
 435 MODULE_LICENSE("GPL");
 436 MODULE_AUTHOR("IBM Corporation");