drivers/scsi/bfa/bfad_intr.c

   1 /*
   2  * Copyright (c) 2005-2009 Brocade Communications Systems, Inc.
   3  * All rights reserved
   4  * www.brocade.com
   5  *
   6  * Linux driver for Brocade Fibre Channel Host Bus Adapter.
   7  *
   8  * This program is free software; you can redistribute it and/or modify it
   9  * under the terms of the GNU General Public License (GPL) Version 2 as
  10  * published by the Free Software Foundation
  11  *
  12  * This program is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * General Public License for more details.
  16  */
  17
  18 #include "bfad_drv.h"
  19 #include "bfad_trcmod.h"
  20
  21 BFA_TRC_FILE(LDRV, INTR);
  22
  23 /**
  24  *  bfa_isr BFA driver interrupt functions
  25  */
  26 static int msix_disable_cb;
  27 static int msix_disable_ct;
  28 module_param(msix_disable_cb, int, S_IRUGO | S_IWUSR);
  29 module_param(msix_disable_ct, int, S_IRUGO | S_IWUSR);
  30 /**
  31  * Line based interrupt handler.
  32  */
  33 static irqreturn_t
  34 bfad_intx(int irq, void *dev_id)
  35 {
  36         struct bfad_s         *bfad = dev_id;
  37         struct list_head         doneq;
  38         unsigned long   flags;
  39         bfa_boolean_t rc;
  40
  41         spin_lock_irqsave(&bfad->bfad_lock, flags);
  42         rc = bfa_intx(&bfad->bfa);
  43         if (!rc) {
  44                 spin_unlock_irqrestore(&bfad->bfad_lock, flags);
  45                 return IRQ_NONE;
  46         }
  47
  48         bfa_comp_deq(&bfad->bfa, &doneq);
  49         spin_unlock_irqrestore(&bfad->bfad_lock, flags);
  50
  51         if (!list_empty(&doneq)) {
  52                 bfa_comp_process(&bfad->bfa, &doneq);
  53
  54                 spin_lock_irqsave(&bfad->bfad_lock, flags);
  55                 bfa_comp_free(&bfad->bfa, &doneq);
  56                 spin_unlock_irqrestore(&bfad->bfad_lock, flags);
  57                 bfa_trc_fp(bfad, irq);
  58         }
  59
  60         return IRQ_HANDLED;
  61
  62 }
  63
  64 static irqreturn_t
  65 bfad_msix(int irq, void *dev_id)
  66 {
  67         struct bfad_msix_s *vec = dev_id;
  68         struct bfad_s *bfad = vec->bfad;
  69         struct list_head doneq;
  70         unsigned long   flags;
  71
  72         spin_lock_irqsave(&bfad->bfad_lock, flags);
  73
  74         bfa_msix(&bfad->bfa, vec->msix.entry);
  75         bfa_comp_deq(&bfad->bfa, &doneq);
  76         spin_unlock_irqrestore(&bfad->bfad_lock, flags);
  77
  78         if (!list_empty(&doneq)) {
  79                 bfa_comp_process(&bfad->bfa, &doneq);
  80
  81                 spin_lock_irqsave(&bfad->bfad_lock, flags);
  82                 bfa_comp_free(&bfad->bfa, &doneq);
  83                 spin_unlock_irqrestore(&bfad->bfad_lock, flags);
  84         }
  85
  86         return IRQ_HANDLED;
  87 }
  88
  89 /**
  90  * Initialize the MSIX entry table.
  91  */
  92 static void
  93 bfad_init_msix_entry(struct bfad_s *bfad, struct msix_entry *msix_entries,
  94                          int mask, int max_bit)
  95 {
  96         int             i;
  97         int             match = 0x00000001;
  98
  99         for (i = 0, bfad->nvec = 0; i < MAX_MSIX_ENTRY; i++) {
 100                 if (mask & match) {
 101                         bfad->msix_tab[bfad->nvec].msix.entry = i;
 102                         bfad->msix_tab[bfad->nvec].bfad = bfad;
 103                         msix_entries[bfad->nvec].entry = i;
 104                         bfad->nvec++;
 105                 }
 106
 107                 match <<= 1;
 108         }
 109
 110 }
 111
 112 int
 113 bfad_install_msix_handler(struct bfad_s *bfad)
 114 {
 115         int             i, error = 0;
 116
 117         for (i = 0; i < bfad->nvec; i++) {
 118                 error = request_irq(bfad->msix_tab[i].msix.vector,
 119                                     (irq_handler_t) bfad_msix, 0,
 120                                     BFAD_DRIVER_NAME, &bfad->msix_tab[i]);
 121                 bfa_trc(bfad, i);
 122                 bfa_trc(bfad, bfad->msix_tab[i].msix.vector);
 123                 if (error) {
 124                         int             j;
 125
 126                         for (j = 0; j < i; j++)
 127                                 free_irq(bfad->msix_tab[j].msix.vector,
 128                                                 &bfad->msix_tab[j]);
 129
 130                         return 1;
 131                 }
 132         }
 133
 134         return 0;
 135 }
 136
 137 /**
 138  * Setup MSIX based interrupt.
 139  */
 140 int
 141 bfad_setup_intr(struct bfad_s *bfad)
 142 {
 143         int error = 0;
 144         u32 mask = 0, i, num_bit = 0, max_bit = 0;
 145         struct msix_entry msix_entries[MAX_MSIX_ENTRY];
 146         struct pci_dev *pdev = bfad->pcidev;
 147
 148         /* Call BFA to get the msix map for this PCI function.  */
 149         bfa_msix_getvecs(&bfad->bfa, &mask, &num_bit, &max_bit);
 150
 151         /* Set up the msix entry table */
 152         bfad_init_msix_entry(bfad, msix_entries, mask, max_bit);
 153
 154         if ((pdev->device == BFA_PCI_DEVICE_ID_CT && !msix_disable_ct) ||
 155             (pdev->device != BFA_PCI_DEVICE_ID_CT && !msix_disable_cb)) {
 156
 157                 error = pci_enable_msix(bfad->pcidev, msix_entries, bfad->nvec);
 158                 if (error) {
 159                         /*
 160                          * Only error number of vector is available.
 161                          * We don't have a mechanism to map multiple
 162                          * interrupts into one vector, so even if we
 163                          * can try to request less vectors, we don't
 164                          * know how to associate interrupt events to
 165                          *  vectors. Linux doesn't dupicate vectors
 166                          * in the MSIX table for this case.
 167                          */
 168
 169                         printk(KERN_WARNING "bfad%d: "
 170                                 "pci_enable_msix failed (%d),"
 171                                 " use line based.\n", bfad->inst_no, error);
 172
 173                         goto line_based;
 174                 }
 175
 176                 /* Save the vectors */
 177                 for (i = 0; i < bfad->nvec; i++) {
 178                         bfa_trc(bfad, msix_entries[i].vector);
 179                         bfad->msix_tab[i].msix.vector = msix_entries[i].vector;
 180                 }
 181
 182                 bfa_msix_init(&bfad->bfa, bfad->nvec);
 183
 184                 bfad->bfad_flags |= BFAD_MSIX_ON;
 185
 186                 return error;
 187         }
 188
 189 line_based:
 190         error = 0;
 191         if (request_irq
 192             (bfad->pcidev->irq, (irq_handler_t) bfad_intx, BFAD_IRQ_FLAGS,
 193              BFAD_DRIVER_NAME, bfad) != 0) {
 194                 /* Enable interrupt handler failed */
 195                 return 1;
 196         }
 197
 198         return error;
 199 }
 200
 201 void
 202 bfad_remove_intr(struct bfad_s *bfad)
 203 {
 204         int             i;
 205
 206         if (bfad->bfad_flags & BFAD_MSIX_ON) {
 207                 for (i = 0; i < bfad->nvec; i++)
 208                         free_irq(bfad->msix_tab[i].msix.vector,
 209                                         &bfad->msix_tab[i]);
 210
 211                 pci_disable_msix(bfad->pcidev);
 212                 bfad->bfad_flags &= ~BFAD_MSIX_ON;
 213         } else {
 214                 free_irq(bfad->pcidev->irq, bfad);
 215         }
 216 }
 217
 218