drivers/scsi/csiostor/csio_isr.c

   1 /*
   2  * This file is part of the Chelsio FCoE driver for Linux.
   3  *
   4  * Copyright (c) 2008-2012 Chelsio Communications, Inc. All rights reserved.
   5  *
   6  * This software is available to you under a choice of one of two
   7  * licenses.  You may choose to be licensed under the terms of the GNU
   8  * General Public License (GPL) Version 2, available from the file
   9  * COPYING in the main directory of this source tree, or the
  10  * OpenIB.org BSD license below:
  11  *
  12  *     Redistribution and use in source and binary forms, with or
  13  *     without modification, are permitted provided that the following
  14  *     conditions are met:
  15  *
  16  *      - Redistributions of source code must retain the above
  17  *        copyright notice, this list of conditions and the following
  18  *        disclaimer.
  19  *
  20  *      - Redistributions in binary form must reproduce the above
  21  *        copyright notice, this list of conditions and the following
  22  *        disclaimer in the documentation and/or other materials
  23  *        provided with the distribution.
  24  *
  25  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  26  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  27  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  28  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  29  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  30  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  31  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  32  * SOFTWARE.
  33  */
  34
  35 #include <linux/kernel.h>
  36 #include <linux/pci.h>
  37 #include <linux/interrupt.h>
  38 #include <linux/cpumask.h>
  39 #include <linux/string.h>
  40
  41 #include "csio_init.h"
  42 #include "csio_hw.h"
  43
  44 static irqreturn_t
  45 csio_nondata_isr(int irq, void *dev_id)
  46 {
  47         struct csio_hw *hw = (struct csio_hw *) dev_id;
  48         int rv;
  49         unsigned long flags;
  50
  51         if (unlikely(!hw))
  52                 return IRQ_NONE;
  53
  54         if (unlikely(pci_channel_offline(hw->pdev))) {
  55                 CSIO_INC_STATS(hw, n_pcich_offline);
  56                 return IRQ_NONE;
  57         }
  58
  59         spin_lock_irqsave(&hw->lock, flags);
  60         csio_hw_slow_intr_handler(hw);
  61         rv = csio_mb_isr_handler(hw);
  62
  63         if (rv == 0 && !(hw->flags & CSIO_HWF_FWEVT_PENDING)) {
  64                 hw->flags |= CSIO_HWF_FWEVT_PENDING;
  65                 spin_unlock_irqrestore(&hw->lock, flags);
  66                 schedule_work(&hw->evtq_work);
  67                 return IRQ_HANDLED;
  68         }
  69         spin_unlock_irqrestore(&hw->lock, flags);
  70         return IRQ_HANDLED;
  71 }
  72
  73 /*
  74  * csio_fwevt_handler - Common FW event handler routine.
  75  * @hw: HW module.
  76  *
  77  * This is the ISR for FW events. It is shared b/w MSIX
  78  * and INTx handlers.
  79  */
  80 static void
  81 csio_fwevt_handler(struct csio_hw *hw)
  82 {
  83         int rv;
  84         unsigned long flags;
  85
  86         rv = csio_fwevtq_handler(hw);
  87
  88         spin_lock_irqsave(&hw->lock, flags);
  89         if (rv == 0 && !(hw->flags & CSIO_HWF_FWEVT_PENDING)) {
  90                 hw->flags |= CSIO_HWF_FWEVT_PENDING;
  91                 spin_unlock_irqrestore(&hw->lock, flags);
  92                 schedule_work(&hw->evtq_work);
  93                 return;
  94         }
  95         spin_unlock_irqrestore(&hw->lock, flags);
  96
  97 } /* csio_fwevt_handler */
  98
  99 /*
 100  * csio_fwevt_isr() - FW events MSIX ISR
 101  * @irq:
 102  * @dev_id:
 103  *
 104  * Process WRs on the FW event queue.
 105  *
 106  */
 107 static irqreturn_t
 108 csio_fwevt_isr(int irq, void *dev_id)
 109 {
 110         struct csio_hw *hw = (struct csio_hw *) dev_id;
 111
 112         if (unlikely(!hw))
 113                 return IRQ_NONE;
 114
 115         if (unlikely(pci_channel_offline(hw->pdev))) {
 116                 CSIO_INC_STATS(hw, n_pcich_offline);
 117                 return IRQ_NONE;
 118         }
 119
 120         csio_fwevt_handler(hw);
 121
 122         return IRQ_HANDLED;
 123 }
 124
 125 /*
 126  * csio_fwevt_isr() - INTx wrapper for handling FW events.
 127  * @irq:
 128  * @dev_id:
 129  */
 130 void
 131 csio_fwevt_intx_handler(struct csio_hw *hw, void *wr, uint32_t len,
 132                            struct csio_fl_dma_buf *flb, void *priv)
 133 {
 134         csio_fwevt_handler(hw);
 135 } /* csio_fwevt_intx_handler */
 136
 137 /*
 138  * csio_process_scsi_cmpl - Process a SCSI WR completion.
 139  * @hw: HW module.
 140  * @wr: The completed WR from the ingress queue.
 141  * @len: Length of the WR.
 142  * @flb: Freelist buffer array.
 143  *
 144  */
 145 static void
 146 csio_process_scsi_cmpl(struct csio_hw *hw, void *wr, uint32_t len,
 147                         struct csio_fl_dma_buf *flb, void *cbfn_q)
 148 {
 149         struct csio_ioreq *ioreq;
 150         uint8_t *scsiwr;
 151         uint8_t subop;
 152         void *cmnd;
 153         unsigned long flags;
 154
 155         ioreq = csio_scsi_cmpl_handler(hw, wr, len, flb, NULL, &scsiwr);
 156         if (likely(ioreq)) {
 157                 if (unlikely(*scsiwr == FW_SCSI_ABRT_CLS_WR)) {
 158                         subop = FW_SCSI_ABRT_CLS_WR_SUB_OPCODE_GET(
 159                                         ((struct fw_scsi_abrt_cls_wr *)
 160                                             scsiwr)->sub_opcode_to_chk_all_io);
 161
 162                         csio_dbg(hw, "%s cmpl recvd ioreq:%p status:%d\n",
 163                                     subop ? "Close" : "Abort",
 164                                     ioreq, ioreq->wr_status);
 165
 166                         spin_lock_irqsave(&hw->lock, flags);
 167                         if (subop)
 168                                 csio_scsi_closed(ioreq,
 169                                                  (struct list_head *)cbfn_q);
 170                         else
 171                                 csio_scsi_aborted(ioreq,
 172                                                   (struct list_head *)cbfn_q);
 173                         /*
 174                          * We call scsi_done for I/Os that driver thinks aborts
 175                          * have timed out. If there is a race caused by FW
 176                          * completing abort at the exact same time that the
 177                          * driver has deteced the abort timeout, the following
 178                          * check prevents calling of scsi_done twice for the
 179                          * same command: once from the eh_abort_handler, another
 180                          * from csio_scsi_isr_handler(). This also avoids the
 181                          * need to check if csio_scsi_cmnd(req) is NULL in the
 182                          * fast path.
 183                          */
 184                         cmnd = csio_scsi_cmnd(ioreq);
 185                         if (unlikely(cmnd == NULL))
 186                                 list_del_init(&ioreq->sm.sm_list);
 187
 188                         spin_unlock_irqrestore(&hw->lock, flags);
 189
 190                         if (unlikely(cmnd == NULL))
 191                                 csio_put_scsi_ioreq_lock(hw,
 192                                                 csio_hw_to_scsim(hw), ioreq);
 193                 } else {
 194                         spin_lock_irqsave(&hw->lock, flags);
 195                         csio_scsi_completed(ioreq, (struct list_head *)cbfn_q);
 196                         spin_unlock_irqrestore(&hw->lock, flags);
 197                 }
 198         }
 199 }
 200
 201 /*
 202  * csio_scsi_isr_handler() - Common SCSI ISR handler.
 203  * @iq: Ingress queue pointer.
 204  *
 205  * Processes SCSI completions on the SCSI IQ indicated by scm->iq_idx
 206  * by calling csio_wr_process_iq_idx. If there are completions on the
 207  * isr_cbfn_q, yank them out into a local queue and call their io_cbfns.
 208  * Once done, add these completions onto the freelist.
 209  * This routine is shared b/w MSIX and INTx.
 210  */
 211 static inline irqreturn_t
 212 csio_scsi_isr_handler(struct csio_q *iq)
 213 {
 214         struct csio_hw *hw = (struct csio_hw *)iq->owner;
 215         LIST_HEAD(cbfn_q);
 216         struct list_head *tmp;
 217         struct csio_scsim *scm;
 218         struct csio_ioreq *ioreq;
 219         int isr_completions = 0;
 220
 221         scm = csio_hw_to_scsim(hw);
 222
 223         if (unlikely(csio_wr_process_iq(hw, iq, csio_process_scsi_cmpl,
 224                                         &cbfn_q) != 0))
 225                 return IRQ_NONE;
 226
 227         /* Call back the completion routines */
 228         list_for_each(tmp, &cbfn_q) {
 229                 ioreq = (struct csio_ioreq *)tmp;
 230                 isr_completions++;
 231                 ioreq->io_cbfn(hw, ioreq);
 232                 /* Release ddp buffer if used for this req */
 233                 if (unlikely(ioreq->dcopy))
 234                         csio_put_scsi_ddp_list_lock(hw, scm, &ioreq->gen_list,
 235                                                     ioreq->nsge);
 236         }
 237
 238         if (isr_completions) {
 239                 /* Return the ioreqs back to ioreq->freelist */
 240                 csio_put_scsi_ioreq_list_lock(hw, scm, &cbfn_q,
 241                                               isr_completions);
 242         }
 243
 244         return IRQ_HANDLED;
 245 }
 246
 247 /*
 248  * csio_scsi_isr() - SCSI MSIX handler
 249  * @irq:
 250  * @dev_id:
 251  *
 252  * This is the top level SCSI MSIX handler. Calls csio_scsi_isr_handler()
 253  * for handling SCSI completions.
 254  */
 255 static irqreturn_t
 256 csio_scsi_isr(int irq, void *dev_id)
 257 {
 258         struct csio_q *iq = (struct csio_q *) dev_id;
 259         struct csio_hw *hw;
 260
 261         if (unlikely(!iq))
 262                 return IRQ_NONE;
 263
 264         hw = (struct csio_hw *)iq->owner;
 265
 266         if (unlikely(pci_channel_offline(hw->pdev))) {
 267                 CSIO_INC_STATS(hw, n_pcich_offline);
 268                 return IRQ_NONE;
 269         }
 270
 271         csio_scsi_isr_handler(iq);
 272
 273         return IRQ_HANDLED;
 274 }
 275
 276 /*
 277  * csio_scsi_intx_handler() - SCSI INTx handler
 278  * @irq:
 279  * @dev_id:
 280  *
 281  * This is the top level SCSI INTx handler. Calls csio_scsi_isr_handler()
 282  * for handling SCSI completions.
 283  */
 284 void
 285 csio_scsi_intx_handler(struct csio_hw *hw, void *wr, uint32_t len,
 286                         struct csio_fl_dma_buf *flb, void *priv)
 287 {
 288         struct csio_q *iq = priv;
 289
 290         csio_scsi_isr_handler(iq);
 291
 292 } /* csio_scsi_intx_handler */
 293
 294 /*
 295  * csio_fcoe_isr() - INTx/MSI interrupt service routine for FCoE.
 296  * @irq:
 297  * @dev_id:
 298  *
 299  *
 300  */
 301 static irqreturn_t
 302 csio_fcoe_isr(int irq, void *dev_id)
 303 {
 304         struct csio_hw *hw = (struct csio_hw *) dev_id;
 305         struct csio_q *intx_q = NULL;
 306         int rv;
 307         irqreturn_t ret = IRQ_NONE;
 308         unsigned long flags;
 309
 310         if (unlikely(!hw))
 311                 return IRQ_NONE;
 312
 313         if (unlikely(pci_channel_offline(hw->pdev))) {
 314                 CSIO_INC_STATS(hw, n_pcich_offline);
 315                 return IRQ_NONE;
 316         }
 317
 318         /* Disable the interrupt for this PCI function. */
 319         if (hw->intr_mode == CSIO_IM_INTX)
 320                 csio_wr_reg32(hw, 0, MYPF_REG(PCIE_PF_CLI_A));
 321
 322         /*
 323          * The read in the following function will flush the
 324          * above write.
 325          */
 326         if (csio_hw_slow_intr_handler(hw))
 327                 ret = IRQ_HANDLED;
 328
 329         /* Get the INTx Forward interrupt IQ. */
 330         intx_q = csio_get_q(hw, hw->intr_iq_idx);
 331
 332         CSIO_DB_ASSERT(intx_q);
 333
 334         /* IQ handler is not possible for intx_q, hence pass in NULL */
 335         if (likely(csio_wr_process_iq(hw, intx_q, NULL, NULL) == 0))
 336                 ret = IRQ_HANDLED;
 337
 338         spin_lock_irqsave(&hw->lock, flags);
 339         rv = csio_mb_isr_handler(hw);
 340         if (rv == 0 && !(hw->flags & CSIO_HWF_FWEVT_PENDING)) {
 341                 hw->flags |= CSIO_HWF_FWEVT_PENDING;
 342                 spin_unlock_irqrestore(&hw->lock, flags);
 343                 schedule_work(&hw->evtq_work);
 344                 return IRQ_HANDLED;
 345         }
 346         spin_unlock_irqrestore(&hw->lock, flags);
 347
 348         return ret;
 349 }
 350
 351 static void
 352 csio_add_msix_desc(struct csio_hw *hw)
 353 {
 354         int i;
 355         struct csio_msix_entries *entryp = &hw->msix_entries[0];
 356         int k = CSIO_EXTRA_VECS;
 357         int len = sizeof(entryp->desc) - 1;
 358         int cnt = hw->num_sqsets + k;
 359
 360         /* Non-data vector */
 361         memset(entryp->desc, 0, len + 1);
 362         snprintf(entryp->desc, len, "csio-%02x:%02x:%x-nondata",
 363                  CSIO_PCI_BUS(hw), CSIO_PCI_DEV(hw), CSIO_PCI_FUNC(hw));
 364
 365         entryp++;
 366         memset(entryp->desc, 0, len + 1);
 367         snprintf(entryp->desc, len, "csio-%02x:%02x:%x-fwevt",
 368                  CSIO_PCI_BUS(hw), CSIO_PCI_DEV(hw), CSIO_PCI_FUNC(hw));
 369         entryp++;
 370
 371         /* Name SCSI vecs */
 372         for (i = k; i < cnt; i++, entryp++) {
 373                 memset(entryp->desc, 0, len + 1);
 374                 snprintf(entryp->desc, len, "csio-%02x:%02x:%x-scsi%d",
 375                          CSIO_PCI_BUS(hw), CSIO_PCI_DEV(hw),
 376                          CSIO_PCI_FUNC(hw), i - CSIO_EXTRA_VECS);
 377         }
 378 }
 379
 380 int
 381 csio_request_irqs(struct csio_hw *hw)
 382 {
 383         int rv, i, j, k = 0;
 384         struct csio_msix_entries *entryp = &hw->msix_entries[0];
 385         struct csio_scsi_cpu_info *info;
 386         struct pci_dev *pdev = hw->pdev;
 387
 388         if (hw->intr_mode != CSIO_IM_MSIX) {
 389                 rv = request_irq(pci_irq_vector(pdev, 0), csio_fcoe_isr,
 390                                 hw->intr_mode == CSIO_IM_MSI ? 0 : IRQF_SHARED,
 391                                 KBUILD_MODNAME, hw);
 392                 if (rv) {
 393                         csio_err(hw, "Failed to allocate interrupt line.\n");
 394                         goto out_free_irqs;
 395                 }
 396
 397                 goto out;
 398         }
 399
 400         /* Add the MSIX vector descriptions */
 401         csio_add_msix_desc(hw);
 402
 403         rv = request_irq(pci_irq_vector(pdev, k), csio_nondata_isr, 0,
 404                          entryp[k].desc, hw);
 405         if (rv) {
 406                 csio_err(hw, "IRQ request failed for vec %d err:%d\n",
 407                          pci_irq_vector(pdev, k), rv);
 408                 goto out_free_irqs;
 409         }
 410
 411         entryp[k++].dev_id = hw;
 412
 413         rv = request_irq(pci_irq_vector(pdev, k), csio_fwevt_isr, 0,
 414                          entryp[k].desc, hw);
 415         if (rv) {
 416                 csio_err(hw, "IRQ request failed for vec %d err:%d\n",
 417                          pci_irq_vector(pdev, k), rv);
 418                 goto out_free_irqs;
 419         }
 420
 421         entryp[k++].dev_id = (void *)hw;
 422
 423         /* Allocate IRQs for SCSI */
 424         for (i = 0; i < hw->num_pports; i++) {
 425                 info = &hw->scsi_cpu_info[i];
 426                 for (j = 0; j < info->max_cpus; j++, k++) {
 427                         struct csio_scsi_qset *sqset = &hw->sqset[i][j];
 428                         struct csio_q *q = hw->wrm.q_arr[sqset->iq_idx];
 429
 430                         rv = request_irq(pci_irq_vector(pdev, k), csio_scsi_isr, 0,
 431                                          entryp[k].desc, q);
 432                         if (rv) {
 433                                 csio_err(hw,
 434                                        "IRQ request failed for vec %d err:%d\n",
 435                                        pci_irq_vector(pdev, k), rv);
 436                                 goto out_free_irqs;
 437                         }
 438
 439                         entryp[k].dev_id = q;
 440
 441                 } /* for all scsi cpus */
 442         } /* for all ports */
 443
 444 out:
 445         hw->flags |= CSIO_HWF_HOST_INTR_ENABLED;
 446         return 0;
 447
 448 out_free_irqs:
 449         for (i = 0; i < k; i++)
 450                 free_irq(pci_irq_vector(pdev, i), hw->msix_entries[i].dev_id);
 451         pci_free_irq_vectors(hw->pdev);
 452         return -EINVAL;
 453 }
 454
 455 /* Reduce per-port max possible CPUs */
 456 static void
 457 csio_reduce_sqsets(struct csio_hw *hw, int cnt)
 458 {
 459         int i;
 460         struct csio_scsi_cpu_info *info;
 461
 462         while (cnt < hw->num_sqsets) {
 463                 for (i = 0; i < hw->num_pports; i++) {
 464                         info = &hw->scsi_cpu_info[i];
 465                         if (info->max_cpus > 1) {
 466                                 info->max_cpus--;
 467                                 hw->num_sqsets--;
 468                                 if (hw->num_sqsets <= cnt)
 469                                         break;
 470                         }
 471                 }
 472         }
 473
 474         csio_dbg(hw, "Reduced sqsets to %d\n", hw->num_sqsets);
 475 }
 476
 477 static int
 478 csio_enable_msix(struct csio_hw *hw)
 479 {
 480         int i, j, k, n, min, cnt;
 481         int extra = CSIO_EXTRA_VECS;
 482         struct csio_scsi_cpu_info *info;
 483         struct irq_affinity desc = { .pre_vectors = 2 };
 484
 485         min = hw->num_pports + extra;
 486         cnt = hw->num_sqsets + extra;
 487
 488         /* Max vectors required based on #niqs configured in fw */
 489         if (hw->flags & CSIO_HWF_USING_SOFT_PARAMS || !csio_is_hw_master(hw))
 490                 cnt = min_t(uint8_t, hw->cfg_niq, cnt);
 491
 492         csio_dbg(hw, "FW supp #niq:%d, trying %d msix's\n", hw->cfg_niq, cnt);
 493
 494         cnt = pci_alloc_irq_vectors_affinity(hw->pdev, min, cnt,
 495                         PCI_IRQ_MSIX | PCI_IRQ_AFFINITY, &desc);
 496         if (cnt < 0)
 497                 return cnt;
 498
 499         if (cnt < (hw->num_sqsets + extra)) {
 500                 csio_dbg(hw, "Reducing sqsets to %d\n", cnt - extra);
 501                 csio_reduce_sqsets(hw, cnt - extra);
 502         }
 503
 504         /* Distribute vectors */
 505         k = 0;
 506         csio_set_nondata_intr_idx(hw, k);
 507         csio_set_mb_intr_idx(csio_hw_to_mbm(hw), k++);
 508         csio_set_fwevt_intr_idx(hw, k++);
 509
 510         for (i = 0; i < hw->num_pports; i++) {
 511                 info = &hw->scsi_cpu_info[i];
 512
 513                 for (j = 0; j < hw->num_scsi_msix_cpus; j++) {
 514                         n = (j % info->max_cpus) +  k;
 515                         hw->sqset[i][j].intr_idx = n;
 516                 }
 517
 518                 k += info->max_cpus;
 519         }
 520
 521         return 0;
 522 }
 523
 524 void
 525 csio_intr_enable(struct csio_hw *hw)
 526 {
 527         hw->intr_mode = CSIO_IM_NONE;
 528         hw->flags &= ~CSIO_HWF_HOST_INTR_ENABLED;
 529
 530         /* Try MSIX, then MSI or fall back to INTx */
 531         if ((csio_msi == 2) && !csio_enable_msix(hw))
 532                 hw->intr_mode = CSIO_IM_MSIX;
 533         else {
 534                 /* Max iqs required based on #niqs configured in fw */
 535                 if (hw->flags & CSIO_HWF_USING_SOFT_PARAMS ||
 536                         !csio_is_hw_master(hw)) {
 537                         int extra = CSIO_EXTRA_MSI_IQS;
 538
 539                         if (hw->cfg_niq < (hw->num_sqsets + extra)) {
 540                                 csio_dbg(hw, "Reducing sqsets to %d\n",
 541                                          hw->cfg_niq - extra);
 542                                 csio_reduce_sqsets(hw, hw->cfg_niq - extra);
 543                         }
 544                 }
 545
 546                 if ((csio_msi == 1) && !pci_enable_msi(hw->pdev))
 547                         hw->intr_mode = CSIO_IM_MSI;
 548                 else
 549                         hw->intr_mode = CSIO_IM_INTX;
 550         }
 551
 552         csio_dbg(hw, "Using %s interrupt mode.\n",
 553                 (hw->intr_mode == CSIO_IM_MSIX) ? "MSIX" :
 554                 ((hw->intr_mode == CSIO_IM_MSI) ? "MSI" : "INTx"));
 555 }
 556
 557 void
 558 csio_intr_disable(struct csio_hw *hw, bool free)
 559 {
 560         csio_hw_intr_disable(hw);
 561
 562         if (free) {
 563                 int i;
 564
 565                 switch (hw->intr_mode) {
 566                 case CSIO_IM_MSIX:
 567                         for (i = 0; i < hw->num_sqsets + CSIO_EXTRA_VECS; i++) {
 568                                 free_irq(pci_irq_vector(hw->pdev, i),
 569                                          hw->msix_entries[i].dev_id);
 570                         }
 571                         break;
 572                 case CSIO_IM_MSI:
 573                 case CSIO_IM_INTX:
 574                         free_irq(pci_irq_vector(hw->pdev, 0), hw);
 575                         break;
 576                 default:
 577                         break;
 578                 }
 579         }
 580
 581         pci_free_irq_vectors(hw->pdev);
 582         hw->intr_mode = CSIO_IM_NONE;
 583         hw->flags &= ~CSIO_HWF_HOST_INTR_ENABLED;
 584 }