sys/ofed/drivers/infiniband/hw/mthca/mthca_reset.c

   1 /*
   2  * Copyright (c) 2004 Topspin Communications.  All rights reserved.
   3  *
   4  * This software is available to you under a choice of one of two
   5  * licenses.  You may choose to be licensed under the terms of the GNU
   6  * General Public License (GPL) Version 2, available from the file
   7  * COPYING in the main directory of this source tree, or the
   8  * OpenIB.org BSD license below:
   9  *
  10  *     Redistribution and use in source and binary forms, with or
  11  *     without modification, are permitted provided that the following
  12  *     conditions are met:
  13  *
  14  *      - Redistributions of source code must retain the above
  15  *        copyright notice, this list of conditions and the following
  16  *        disclaimer.
  17  *
  18  *      - Redistributions in binary form must reproduce the above
  19  *        copyright notice, this list of conditions and the following
  20  *        disclaimer in the documentation and/or other materials
  21  *        provided with the distribution.
  22  *
  23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  24  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  25  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  26  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  27  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  28  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  29  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  30  * SOFTWARE.
  31  */
  32
  33 #include <linux/errno.h>
  34 #include <linux/pci.h>
  35 #include <linux/delay.h>
  36 #include <linux/slab.h>
  37
  38 #include "mthca_dev.h"
  39 #include "mthca_cmd.h"
  40
  41 int mthca_reset(struct mthca_dev *mdev)
  42 {
  43         int i;
  44         int err = 0;
  45         u32 *hca_header    = NULL;
  46 #ifdef __linux__
  47         u32 *bridge_header = NULL;
  48 #endif
  49         struct pci_dev *bridge = NULL;
  50 #ifdef __linux__
  51         int bridge_pcix_cap = 0;
  52 #endif
  53         int hca_pcie_cap = 0;
  54         int hca_pcix_cap = 0;
  55
  56         u16 devctl;
  57         u16 linkctl;
  58
  59 #define MTHCA_RESET_OFFSET 0xf0010
  60 #define MTHCA_RESET_VALUE  swab32(1)
  61
  62         /*
  63          * Reset the chip.  This is somewhat ugly because we have to
  64          * save off the PCI header before reset and then restore it
  65          * after the chip reboots.  We skip config space offsets 22
  66          * and 23 since those have a special meaning.
  67          *
  68          * To make matters worse, for Tavor (PCI-X HCA) we have to
  69          * find the associated bridge device and save off its PCI
  70          * header as well.
  71          */
  72
  73         if (!(mdev->mthca_flags & MTHCA_FLAG_PCIE)) {
  74                 /* Look for the bridge -- its device ID will be 2 more
  75                    than HCA's device ID. */
  76 #ifdef __linux__
  77                 while ((bridge = pci_get_device(mdev->pdev->vendor,
  78                                                 mdev->pdev->device + 2,
  79                                                 bridge)) != NULL) {
  80                         if (bridge->hdr_type    == PCI_HEADER_TYPE_BRIDGE &&
  81                             bridge->subordinate == mdev->pdev->bus) {
  82                                 mthca_dbg(mdev, "Found bridge: %s\n",
  83                                           pci_name(bridge));
  84                                 break;
  85                         }
  86                 }
  87
  88                 if (!bridge) {
  89                         /*
  90                          * Didn't find a bridge for a Tavor device --
  91                          * assume we're in no-bridge mode and hope for
  92                          * the best.
  93                          */
  94                         mthca_warn(mdev, "No bridge found for %s\n",
  95                                   pci_name(mdev->pdev));
  96                 }
  97 #else
  98                 mthca_warn(mdev, "Reset on PCI-X is not supported.\n");
  99                 goto out;
 100
 101 #endif
 102         }
 103
 104         /* For Arbel do we need to save off the full 4K PCI Express header?? */
 105         hca_header = kmalloc(256, GFP_KERNEL);
 106         if (!hca_header) {
 107                 err = -ENOMEM;
 108                 mthca_err(mdev, "Couldn't allocate memory to save HCA "
 109                           "PCI header, aborting.\n");
 110                 goto out;
 111         }
 112
 113         for (i = 0; i < 64; ++i) {
 114                 if (i == 22 || i == 23)
 115                         continue;
 116                 if (pci_read_config_dword(mdev->pdev, i * 4, hca_header + i)) {
 117                         err = -ENODEV;
 118                         mthca_err(mdev, "Couldn't save HCA "
 119                                   "PCI header, aborting.\n");
 120                         goto out;
 121                 }
 122         }
 123
 124         hca_pcix_cap = pci_find_capability(mdev->pdev, PCI_CAP_ID_PCIX);
 125         hca_pcie_cap = pci_find_capability(mdev->pdev, PCI_CAP_ID_EXP);
 126
 127 #ifdef __linux__
 128         if (bridge) {
 129                 bridge_header = kmalloc(256, GFP_KERNEL);
 130                 if (!bridge_header) {
 131                         err = -ENOMEM;
 132                         mthca_err(mdev, "Couldn't allocate memory to save HCA "
 133                                   "bridge PCI header, aborting.\n");
 134                         goto out;
 135                 }
 136
 137                 for (i = 0; i < 64; ++i) {
 138                         if (i == 22 || i == 23)
 139                                 continue;
 140                         if (pci_read_config_dword(bridge, i * 4, bridge_header + i)) {
 141                                 err = -ENODEV;
 142                                 mthca_err(mdev, "Couldn't save HCA bridge "
 143                                           "PCI header, aborting.\n");
 144                                 goto out;
 145                         }
 146                 }
 147                 bridge_pcix_cap = pci_find_capability(bridge, PCI_CAP_ID_PCIX);
 148                 if (!bridge_pcix_cap) {
 149                                 err = -ENODEV;
 150                                 mthca_err(mdev, "Couldn't locate HCA bridge "
 151                                           "PCI-X capability, aborting.\n");
 152                                 goto out;
 153                 }
 154         }
 155 #endif
 156
 157         /* actually hit reset */
 158         {
 159                 void __iomem *reset = ioremap(pci_resource_start(mdev->pdev, 0) +
 160                                               MTHCA_RESET_OFFSET, 4);
 161
 162                 if (!reset) {
 163                         err = -ENOMEM;
 164                         mthca_err(mdev, "Couldn't map HCA reset register, "
 165                                   "aborting.\n");
 166                         goto out;
 167                 }
 168
 169                 writel(MTHCA_RESET_VALUE, reset);
 170                 iounmap(reset);
 171         }
 172
 173         /* Docs say to wait one second before accessing device */
 174         msleep(1000);
 175
 176         /* Now wait for PCI device to start responding again */
 177         {
 178                 u32 v;
 179                 int c = 0;
 180
 181                 for (c = 0; c < 100; ++c) {
 182                         if (pci_read_config_dword(bridge ? bridge : mdev->pdev, 0, &v)) {
 183                                 err = -ENODEV;
 184                                 mthca_err(mdev, "Couldn't access HCA after reset, "
 185                                           "aborting.\n");
 186                                 goto out;
 187                         }
 188
 189                         if (v != 0xffffffff)
 190                                 goto good;
 191
 192                         msleep(100);
 193                 }
 194
 195                 err = -ENODEV;
 196                 mthca_err(mdev, "PCI device did not come back after reset, "
 197                           "aborting.\n");
 198                 goto out;
 199         }
 200
 201 good:
 202 #ifdef __linux__
 203         /* Now restore the PCI headers */
 204         if (bridge) {
 205                 if (pci_write_config_dword(bridge, bridge_pcix_cap + 0x8,
 206                                  bridge_header[(bridge_pcix_cap + 0x8) / 4])) {
 207                         err = -ENODEV;
 208                         mthca_err(mdev, "Couldn't restore HCA bridge Upstream "
 209                                   "split transaction control, aborting.\n");
 210                         goto out;
 211                 }
 212                 if (pci_write_config_dword(bridge, bridge_pcix_cap + 0xc,
 213                                  bridge_header[(bridge_pcix_cap + 0xc) / 4])) {
 214                         err = -ENODEV;
 215                         mthca_err(mdev, "Couldn't restore HCA bridge Downstream "
 216                                   "split transaction control, aborting.\n");
 217                         goto out;
 218                 }
 219                 /*
 220                  * Bridge control register is at 0x3e, so we'll
 221                  * naturally restore it last in this loop.
 222                  */
 223                 for (i = 0; i < 16; ++i) {
 224                         if (i * 4 == PCI_COMMAND)
 225                                 continue;
 226
 227                         if (pci_write_config_dword(bridge, i * 4, bridge_header[i])) {
 228                                 err = -ENODEV;
 229                                 mthca_err(mdev, "Couldn't restore HCA bridge reg %x, "
 230                                           "aborting.\n", i);
 231                                 goto out;
 232                         }
 233                 }
 234
 235                 if (pci_write_config_dword(bridge, PCI_COMMAND,
 236                                            bridge_header[PCI_COMMAND / 4])) {
 237                         err = -ENODEV;
 238                         mthca_err(mdev, "Couldn't restore HCA bridge COMMAND, "
 239                                   "aborting.\n");
 240                         goto out;
 241                 }
 242         }
 243 #endif
 244
 245         if (hca_pcix_cap) {
 246                 if (pci_write_config_dword(mdev->pdev, hca_pcix_cap,
 247                                  hca_header[hca_pcix_cap / 4])) {
 248                         err = -ENODEV;
 249                         mthca_err(mdev, "Couldn't restore HCA PCI-X "
 250                                   "command register, aborting.\n");
 251                         goto out;
 252                 }
 253         }
 254
 255         if (hca_pcie_cap) {
 256                 devctl = hca_header[(hca_pcie_cap + PCI_EXP_DEVCTL) / 4];
 257                 if (pci_write_config_word(mdev->pdev, hca_pcie_cap + PCI_EXP_DEVCTL,
 258                                            devctl)) {
 259                         err = -ENODEV;
 260                         mthca_err(mdev, "Couldn't restore HCA PCI Express "
 261                                   "Device Control register, aborting.\n");
 262                         goto out;
 263                 }
 264                 linkctl = hca_header[(hca_pcie_cap + PCI_EXP_LNKCTL) / 4];
 265                 if (pci_write_config_word(mdev->pdev, hca_pcie_cap + PCI_EXP_LNKCTL,
 266                                            linkctl)) {
 267                         err = -ENODEV;
 268                         mthca_err(mdev, "Couldn't restore HCA PCI Express "
 269                                   "Link control register, aborting.\n");
 270                         goto out;
 271                 }
 272         }
 273
 274         for (i = 0; i < 16; ++i) {
 275                 if (i * 4 == PCI_COMMAND)
 276                         continue;
 277
 278                 if (pci_write_config_dword(mdev->pdev, i * 4, hca_header[i])) {
 279                         err = -ENODEV;
 280                         mthca_err(mdev, "Couldn't restore HCA reg %x, "
 281                                   "aborting.\n", i);
 282                         goto out;
 283                 }
 284         }
 285
 286         if (pci_write_config_dword(mdev->pdev, PCI_COMMAND,
 287                                    hca_header[PCI_COMMAND / 4])) {
 288                 err = -ENODEV;
 289                 mthca_err(mdev, "Couldn't restore HCA COMMAND, "
 290                           "aborting.\n");
 291                 goto out;
 292         }
 293
 294 out:
 295 #ifdef __linux__
 296         if (bridge)
 297                 pci_dev_put(bridge);
 298         kfree(bridge_header);
 299 #endif
 300         kfree(hca_header);
 301
 302         return err;
 303 }