drivers/s390/net/ism_drv.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * ISM driver for s390.
   4  *
   5  * Copyright IBM Corp. 2018
   6  */
   7 #define KMSG_COMPONENT "ism"
   8 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
   9
  10 #include <linux/module.h>
  11 #include <linux/types.h>
  12 #include <linux/interrupt.h>
  13 #include <linux/device.h>
  14 #include <linux/pci.h>
  15 #include <linux/err.h>
  16 #include <linux/ctype.h>
  17 #include <linux/processor.h>
  18 #include <net/smc.h>
  19
  20 #include <asm/debug.h>
  21
  22 #include "ism.h"
  23
  24 MODULE_DESCRIPTION("ISM driver for s390");
  25 MODULE_LICENSE("GPL");
  26
  27 #define PCI_DEVICE_ID_IBM_ISM 0x04ED
  28 #define DRV_NAME "ism"
  29
  30 static const struct pci_device_id ism_device_table[] = {
  31         { PCI_VDEVICE(IBM, PCI_DEVICE_ID_IBM_ISM), 0 },
  32         { 0, }
  33 };
  34 MODULE_DEVICE_TABLE(pci, ism_device_table);
  35
  36 static debug_info_t *ism_debug_info;
  37
  38 static int ism_cmd(struct ism_dev *ism, void *cmd)
  39 {
  40         struct ism_req_hdr *req = cmd;
  41         struct ism_resp_hdr *resp = cmd;
  42
  43         __ism_write_cmd(ism, req + 1, sizeof(*req), req->len - sizeof(*req));
  44         __ism_write_cmd(ism, req, 0, sizeof(*req));
  45
  46         WRITE_ONCE(resp->ret, ISM_ERROR);
  47
  48         __ism_read_cmd(ism, resp, 0, sizeof(*resp));
  49         if (resp->ret) {
  50                 debug_text_event(ism_debug_info, 0, "cmd failure");
  51                 debug_event(ism_debug_info, 0, resp, sizeof(*resp));
  52                 goto out;
  53         }
  54         __ism_read_cmd(ism, resp + 1, sizeof(*resp), resp->len - sizeof(*resp));
  55 out:
  56         return resp->ret;
  57 }
  58
  59 static int ism_cmd_simple(struct ism_dev *ism, u32 cmd_code)
  60 {
  61         union ism_cmd_simple cmd;
  62
  63         memset(&cmd, 0, sizeof(cmd));
  64         cmd.request.hdr.cmd = cmd_code;
  65         cmd.request.hdr.len = sizeof(cmd.request);
  66
  67         return ism_cmd(ism, &cmd);
  68 }
  69
  70 static int query_info(struct ism_dev *ism)
  71 {
  72         union ism_qi cmd;
  73
  74         memset(&cmd, 0, sizeof(cmd));
  75         cmd.request.hdr.cmd = ISM_QUERY_INFO;
  76         cmd.request.hdr.len = sizeof(cmd.request);
  77
  78         if (ism_cmd(ism, &cmd))
  79                 goto out;
  80
  81         debug_text_event(ism_debug_info, 3, "query info");
  82         debug_event(ism_debug_info, 3, &cmd.response, sizeof(cmd.response));
  83 out:
  84         return 0;
  85 }
  86
  87 static int register_sba(struct ism_dev *ism)
  88 {
  89         union ism_reg_sba cmd;
  90         dma_addr_t dma_handle;
  91         struct ism_sba *sba;
  92
  93         sba = dma_alloc_coherent(&ism->pdev->dev, PAGE_SIZE, &dma_handle,
  94                                  GFP_KERNEL);
  95         if (!sba)
  96                 return -ENOMEM;
  97
  98         memset(&cmd, 0, sizeof(cmd));
  99         cmd.request.hdr.cmd = ISM_REG_SBA;
 100         cmd.request.hdr.len = sizeof(cmd.request);
 101         cmd.request.sba = dma_handle;
 102
 103         if (ism_cmd(ism, &cmd)) {
 104                 dma_free_coherent(&ism->pdev->dev, PAGE_SIZE, sba, dma_handle);
 105                 return -EIO;
 106         }
 107
 108         ism->sba = sba;
 109         ism->sba_dma_addr = dma_handle;
 110
 111         return 0;
 112 }
 113
 114 static int register_ieq(struct ism_dev *ism)
 115 {
 116         union ism_reg_ieq cmd;
 117         dma_addr_t dma_handle;
 118         struct ism_eq *ieq;
 119
 120         ieq = dma_alloc_coherent(&ism->pdev->dev, PAGE_SIZE, &dma_handle,
 121                                  GFP_KERNEL);
 122         if (!ieq)
 123                 return -ENOMEM;
 124
 125         memset(&cmd, 0, sizeof(cmd));
 126         cmd.request.hdr.cmd = ISM_REG_IEQ;
 127         cmd.request.hdr.len = sizeof(cmd.request);
 128         cmd.request.ieq = dma_handle;
 129         cmd.request.len = sizeof(*ieq);
 130
 131         if (ism_cmd(ism, &cmd)) {
 132                 dma_free_coherent(&ism->pdev->dev, PAGE_SIZE, ieq, dma_handle);
 133                 return -EIO;
 134         }
 135
 136         ism->ieq = ieq;
 137         ism->ieq_idx = -1;
 138         ism->ieq_dma_addr = dma_handle;
 139
 140         return 0;
 141 }
 142
 143 static int unregister_sba(struct ism_dev *ism)
 144 {
 145         int ret;
 146
 147         if (!ism->sba)
 148                 return 0;
 149
 150         ret = ism_cmd_simple(ism, ISM_UNREG_SBA);
 151         if (ret && ret != ISM_ERROR)
 152                 return -EIO;
 153
 154         dma_free_coherent(&ism->pdev->dev, PAGE_SIZE,
 155                           ism->sba, ism->sba_dma_addr);
 156
 157         ism->sba = NULL;
 158         ism->sba_dma_addr = 0;
 159
 160         return 0;
 161 }
 162
 163 static int unregister_ieq(struct ism_dev *ism)
 164 {
 165         int ret;
 166
 167         if (!ism->ieq)
 168                 return 0;
 169
 170         ret = ism_cmd_simple(ism, ISM_UNREG_IEQ);
 171         if (ret && ret != ISM_ERROR)
 172                 return -EIO;
 173
 174         dma_free_coherent(&ism->pdev->dev, PAGE_SIZE,
 175                           ism->ieq, ism->ieq_dma_addr);
 176
 177         ism->ieq = NULL;
 178         ism->ieq_dma_addr = 0;
 179
 180         return 0;
 181 }
 182
 183 static int ism_read_local_gid(struct ism_dev *ism)
 184 {
 185         union ism_read_gid cmd;
 186         int ret;
 187
 188         memset(&cmd, 0, sizeof(cmd));
 189         cmd.request.hdr.cmd = ISM_READ_GID;
 190         cmd.request.hdr.len = sizeof(cmd.request);
 191
 192         ret = ism_cmd(ism, &cmd);
 193         if (ret)
 194                 goto out;
 195
 196         ism->smcd->local_gid = cmd.response.gid;
 197 out:
 198         return ret;
 199 }
 200
 201 static int ism_query_rgid(struct smcd_dev *smcd, u64 rgid, u32 vid_valid,
 202                           u32 vid)
 203 {
 204         struct ism_dev *ism = smcd->priv;
 205         union ism_query_rgid cmd;
 206
 207         memset(&cmd, 0, sizeof(cmd));
 208         cmd.request.hdr.cmd = ISM_QUERY_RGID;
 209         cmd.request.hdr.len = sizeof(cmd.request);
 210
 211         cmd.request.rgid = rgid;
 212         cmd.request.vlan_valid = vid_valid;
 213         cmd.request.vlan_id = vid;
 214
 215         return ism_cmd(ism, &cmd);
 216 }
 217
 218 static void ism_free_dmb(struct ism_dev *ism, struct smcd_dmb *dmb)
 219 {
 220         clear_bit(dmb->sba_idx, ism->sba_bitmap);
 221         dma_free_coherent(&ism->pdev->dev, dmb->dmb_len,
 222                           dmb->cpu_addr, dmb->dma_addr);
 223 }
 224
 225 static int ism_alloc_dmb(struct ism_dev *ism, struct smcd_dmb *dmb)
 226 {
 227         unsigned long bit;
 228
 229         if (PAGE_ALIGN(dmb->dmb_len) > dma_get_max_seg_size(&ism->pdev->dev))
 230                 return -EINVAL;
 231
 232         if (!dmb->sba_idx) {
 233                 bit = find_next_zero_bit(ism->sba_bitmap, ISM_NR_DMBS,
 234                                          ISM_DMB_BIT_OFFSET);
 235                 if (bit == ISM_NR_DMBS)
 236                         return -ENOSPC;
 237
 238                 dmb->sba_idx = bit;
 239         }
 240         if (dmb->sba_idx < ISM_DMB_BIT_OFFSET ||
 241             test_and_set_bit(dmb->sba_idx, ism->sba_bitmap))
 242                 return -EINVAL;
 243
 244         dmb->cpu_addr = dma_alloc_coherent(&ism->pdev->dev, dmb->dmb_len,
 245                                            &dmb->dma_addr,
 246                                            GFP_KERNEL | __GFP_NOWARN | __GFP_NOMEMALLOC | __GFP_COMP | __GFP_NORETRY);
 247         if (!dmb->cpu_addr)
 248                 clear_bit(dmb->sba_idx, ism->sba_bitmap);
 249
 250         return dmb->cpu_addr ? 0 : -ENOMEM;
 251 }
 252
 253 static int ism_register_dmb(struct smcd_dev *smcd, struct smcd_dmb *dmb)
 254 {
 255         struct ism_dev *ism = smcd->priv;
 256         union ism_reg_dmb cmd;
 257         int ret;
 258
 259         ret = ism_alloc_dmb(ism, dmb);
 260         if (ret)
 261                 goto out;
 262
 263         memset(&cmd, 0, sizeof(cmd));
 264         cmd.request.hdr.cmd = ISM_REG_DMB;
 265         cmd.request.hdr.len = sizeof(cmd.request);
 266
 267         cmd.request.dmb = dmb->dma_addr;
 268         cmd.request.dmb_len = dmb->dmb_len;
 269         cmd.request.sba_idx = dmb->sba_idx;
 270         cmd.request.vlan_valid = dmb->vlan_valid;
 271         cmd.request.vlan_id = dmb->vlan_id;
 272         cmd.request.rgid = dmb->rgid;
 273
 274         ret = ism_cmd(ism, &cmd);
 275         if (ret) {
 276                 ism_free_dmb(ism, dmb);
 277                 goto out;
 278         }
 279         dmb->dmb_tok = cmd.response.dmb_tok;
 280 out:
 281         return ret;
 282 }
 283
 284 static int ism_unregister_dmb(struct smcd_dev *smcd, struct smcd_dmb *dmb)
 285 {
 286         struct ism_dev *ism = smcd->priv;
 287         union ism_unreg_dmb cmd;
 288         int ret;
 289
 290         memset(&cmd, 0, sizeof(cmd));
 291         cmd.request.hdr.cmd = ISM_UNREG_DMB;
 292         cmd.request.hdr.len = sizeof(cmd.request);
 293
 294         cmd.request.dmb_tok = dmb->dmb_tok;
 295
 296         ret = ism_cmd(ism, &cmd);
 297         if (ret && ret != ISM_ERROR)
 298                 goto out;
 299
 300         ism_free_dmb(ism, dmb);
 301 out:
 302         return ret;
 303 }
 304
 305 static int ism_add_vlan_id(struct smcd_dev *smcd, u64 vlan_id)
 306 {
 307         struct ism_dev *ism = smcd->priv;
 308         union ism_set_vlan_id cmd;
 309
 310         memset(&cmd, 0, sizeof(cmd));
 311         cmd.request.hdr.cmd = ISM_ADD_VLAN_ID;
 312         cmd.request.hdr.len = sizeof(cmd.request);
 313
 314         cmd.request.vlan_id = vlan_id;
 315
 316         return ism_cmd(ism, &cmd);
 317 }
 318
 319 static int ism_del_vlan_id(struct smcd_dev *smcd, u64 vlan_id)
 320 {
 321         struct ism_dev *ism = smcd->priv;
 322         union ism_set_vlan_id cmd;
 323
 324         memset(&cmd, 0, sizeof(cmd));
 325         cmd.request.hdr.cmd = ISM_DEL_VLAN_ID;
 326         cmd.request.hdr.len = sizeof(cmd.request);
 327
 328         cmd.request.vlan_id = vlan_id;
 329
 330         return ism_cmd(ism, &cmd);
 331 }
 332
 333 static int ism_set_vlan_required(struct smcd_dev *smcd)
 334 {
 335         return ism_cmd_simple(smcd->priv, ISM_SET_VLAN);
 336 }
 337
 338 static int ism_reset_vlan_required(struct smcd_dev *smcd)
 339 {
 340         return ism_cmd_simple(smcd->priv, ISM_RESET_VLAN);
 341 }
 342
 343 static int ism_signal_ieq(struct smcd_dev *smcd, u64 rgid, u32 trigger_irq,
 344                           u32 event_code, u64 info)
 345 {
 346         struct ism_dev *ism = smcd->priv;
 347         union ism_sig_ieq cmd;
 348
 349         memset(&cmd, 0, sizeof(cmd));
 350         cmd.request.hdr.cmd = ISM_SIGNAL_IEQ;
 351         cmd.request.hdr.len = sizeof(cmd.request);
 352
 353         cmd.request.rgid = rgid;
 354         cmd.request.trigger_irq = trigger_irq;
 355         cmd.request.event_code = event_code;
 356         cmd.request.info = info;
 357
 358         return ism_cmd(ism, &cmd);
 359 }
 360
 361 static unsigned int max_bytes(unsigned int start, unsigned int len,
 362                               unsigned int boundary)
 363 {
 364         return min(boundary - (start & (boundary - 1)), len);
 365 }
 366
 367 static int ism_move(struct smcd_dev *smcd, u64 dmb_tok, unsigned int idx,
 368                     bool sf, unsigned int offset, void *data, unsigned int size)
 369 {
 370         struct ism_dev *ism = smcd->priv;
 371         unsigned int bytes;
 372         u64 dmb_req;
 373         int ret;
 374
 375         while (size) {
 376                 bytes = max_bytes(offset, size, PAGE_SIZE);
 377                 dmb_req = ISM_CREATE_REQ(dmb_tok, idx, size == bytes ? sf : 0,
 378                                          offset);
 379
 380                 ret = __ism_move(ism, dmb_req, data, bytes);
 381                 if (ret)
 382                         return ret;
 383
 384                 size -= bytes;
 385                 data += bytes;
 386                 offset += bytes;
 387         }
 388
 389         return 0;
 390 }
 391
 392 static struct ism_systemeid SYSTEM_EID = {
 393         .seid_string = "IBM-SYSZ-ISMSEID00000000",
 394         .serial_number = "0000",
 395         .type = "0000",
 396 };
 397
 398 static void ism_create_system_eid(void)
 399 {
 400         struct cpuid id;
 401         u16 ident_tail;
 402         char tmp[5];
 403
 404         get_cpu_id(&id);
 405         ident_tail = (u16)(id.ident & ISM_IDENT_MASK);
 406         snprintf(tmp, 5, "%04X", ident_tail);
 407         memcpy(&SYSTEM_EID.serial_number, tmp, 4);
 408         snprintf(tmp, 5, "%04X", id.machine);
 409         memcpy(&SYSTEM_EID.type, tmp, 4);
 410 }
 411
 412 static void ism_get_system_eid(struct smcd_dev *smcd, u8 **eid)
 413 {
 414         *eid = &SYSTEM_EID.seid_string[0];
 415 }
 416
 417 static u16 ism_get_chid(struct smcd_dev *smcd)
 418 {
 419         struct ism_dev *ismdev;
 420
 421         ismdev = (struct ism_dev *)smcd->priv;
 422         if (!ismdev || !ismdev->pdev)
 423                 return 0;
 424
 425         return to_zpci(ismdev->pdev)->pchid;
 426 }
 427
 428 static void ism_handle_event(struct ism_dev *ism)
 429 {
 430         struct smcd_event *entry;
 431
 432         while ((ism->ieq_idx + 1) != READ_ONCE(ism->ieq->header.idx)) {
 433                 if (++(ism->ieq_idx) == ARRAY_SIZE(ism->ieq->entry))
 434                         ism->ieq_idx = 0;
 435
 436                 entry = &ism->ieq->entry[ism->ieq_idx];
 437                 debug_event(ism_debug_info, 2, entry, sizeof(*entry));
 438                 smcd_handle_event(ism->smcd, entry);
 439         }
 440 }
 441
 442 static irqreturn_t ism_handle_irq(int irq, void *data)
 443 {
 444         struct ism_dev *ism = data;
 445         unsigned long bit, end;
 446         unsigned long *bv;
 447
 448         bv = (void *) &ism->sba->dmb_bits[ISM_DMB_WORD_OFFSET];
 449         end = sizeof(ism->sba->dmb_bits) * BITS_PER_BYTE - ISM_DMB_BIT_OFFSET;
 450
 451         spin_lock(&ism->lock);
 452         ism->sba->s = 0;
 453         barrier();
 454         for (bit = 0;;) {
 455                 bit = find_next_bit_inv(bv, end, bit);
 456                 if (bit >= end)
 457                         break;
 458
 459                 clear_bit_inv(bit, bv);
 460                 ism->sba->dmbe_mask[bit + ISM_DMB_BIT_OFFSET] = 0;
 461                 barrier();
 462                 smcd_handle_irq(ism->smcd, bit + ISM_DMB_BIT_OFFSET);
 463         }
 464
 465         if (ism->sba->e) {
 466                 ism->sba->e = 0;
 467                 barrier();
 468                 ism_handle_event(ism);
 469         }
 470         spin_unlock(&ism->lock);
 471         return IRQ_HANDLED;
 472 }
 473
 474 static const struct smcd_ops ism_ops = {
 475         .query_remote_gid = ism_query_rgid,
 476         .register_dmb = ism_register_dmb,
 477         .unregister_dmb = ism_unregister_dmb,
 478         .add_vlan_id = ism_add_vlan_id,
 479         .del_vlan_id = ism_del_vlan_id,
 480         .set_vlan_required = ism_set_vlan_required,
 481         .reset_vlan_required = ism_reset_vlan_required,
 482         .signal_event = ism_signal_ieq,
 483         .move_data = ism_move,
 484         .get_system_eid = ism_get_system_eid,
 485         .get_chid = ism_get_chid,
 486 };
 487
 488 static int ism_dev_init(struct ism_dev *ism)
 489 {
 490         struct pci_dev *pdev = ism->pdev;
 491         int ret;
 492
 493         ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_MSI);
 494         if (ret <= 0)
 495                 goto out;
 496
 497         ret = request_irq(pci_irq_vector(pdev, 0), ism_handle_irq, 0,
 498                           pci_name(pdev), ism);
 499         if (ret)
 500                 goto free_vectors;
 501
 502         ret = register_sba(ism);
 503         if (ret)
 504                 goto free_irq;
 505
 506         ret = register_ieq(ism);
 507         if (ret)
 508                 goto unreg_sba;
 509
 510         ret = ism_read_local_gid(ism);
 511         if (ret)
 512                 goto unreg_ieq;
 513
 514         if (!ism_add_vlan_id(ism->smcd, ISM_RESERVED_VLANID))
 515                 /* hardware is V2 capable */
 516                 ism_create_system_eid();
 517
 518         ret = smcd_register_dev(ism->smcd);
 519         if (ret)
 520                 goto unreg_ieq;
 521
 522         query_info(ism);
 523         return 0;
 524
 525 unreg_ieq:
 526         unregister_ieq(ism);
 527 unreg_sba:
 528         unregister_sba(ism);
 529 free_irq:
 530         free_irq(pci_irq_vector(pdev, 0), ism);
 531 free_vectors:
 532         pci_free_irq_vectors(pdev);
 533 out:
 534         return ret;
 535 }
 536
 537 static int ism_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 538 {
 539         struct ism_dev *ism;
 540         int ret;
 541
 542         ism = kzalloc(sizeof(*ism), GFP_KERNEL);
 543         if (!ism)
 544                 return -ENOMEM;
 545
 546         spin_lock_init(&ism->lock);
 547         dev_set_drvdata(&pdev->dev, ism);
 548         ism->pdev = pdev;
 549
 550         ret = pci_enable_device_mem(pdev);
 551         if (ret)
 552                 goto err;
 553
 554         ret = pci_request_mem_regions(pdev, DRV_NAME);
 555         if (ret)
 556                 goto err_disable;
 557
 558         ret = pci_set_dma_mask(pdev, DMA_BIT_MASK(64));
 559         if (ret)
 560                 goto err_resource;
 561
 562         dma_set_seg_boundary(&pdev->dev, SZ_1M - 1);
 563         dma_set_max_seg_size(&pdev->dev, SZ_1M);
 564         pci_set_master(pdev);
 565
 566         ism->smcd = smcd_alloc_dev(&pdev->dev, dev_name(&pdev->dev), &ism_ops,
 567                                    ISM_NR_DMBS);
 568         if (!ism->smcd) {
 569                 ret = -ENOMEM;
 570                 goto err_resource;
 571         }
 572
 573         ism->smcd->priv = ism;
 574         ret = ism_dev_init(ism);
 575         if (ret)
 576                 goto err_free;
 577
 578         return 0;
 579
 580 err_free:
 581         smcd_free_dev(ism->smcd);
 582 err_resource:
 583         pci_release_mem_regions(pdev);
 584 err_disable:
 585         pci_disable_device(pdev);
 586 err:
 587         kfree(ism);
 588         dev_set_drvdata(&pdev->dev, NULL);
 589         return ret;
 590 }
 591
 592 static void ism_dev_exit(struct ism_dev *ism)
 593 {
 594         struct pci_dev *pdev = ism->pdev;
 595
 596         smcd_unregister_dev(ism->smcd);
 597         if (SYSTEM_EID.serial_number[0] != '0' ||
 598             SYSTEM_EID.type[0] != '0')
 599                 ism_del_vlan_id(ism->smcd, ISM_RESERVED_VLANID);
 600         unregister_ieq(ism);
 601         unregister_sba(ism);
 602         free_irq(pci_irq_vector(pdev, 0), ism);
 603         pci_free_irq_vectors(pdev);
 604 }
 605
 606 static void ism_remove(struct pci_dev *pdev)
 607 {
 608         struct ism_dev *ism = dev_get_drvdata(&pdev->dev);
 609
 610         ism_dev_exit(ism);
 611
 612         smcd_free_dev(ism->smcd);
 613         pci_release_mem_regions(pdev);
 614         pci_disable_device(pdev);
 615         dev_set_drvdata(&pdev->dev, NULL);
 616         kfree(ism);
 617 }
 618
 619 static struct pci_driver ism_driver = {
 620         .name     = DRV_NAME,
 621         .id_table = ism_device_table,
 622         .probe    = ism_probe,
 623         .remove   = ism_remove,
 624 };
 625
 626 static int __init ism_init(void)
 627 {
 628         int ret;
 629
 630         ism_debug_info = debug_register("ism", 2, 1, 16);
 631         if (!ism_debug_info)
 632                 return -ENODEV;
 633
 634         debug_register_view(ism_debug_info, &debug_hex_ascii_view);
 635         ret = pci_register_driver(&ism_driver);
 636         if (ret)
 637                 debug_unregister(ism_debug_info);
 638
 639         return ret;
 640 }
 641
 642 static void __exit ism_exit(void)
 643 {
 644         pci_unregister_driver(&ism_driver);
 645         debug_unregister(ism_debug_info);
 646 }
 647
 648 module_init(ism_init);
 649 module_exit(ism_exit);