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         u32 *bridge_header = NULL;
  47         struct pci_dev *bridge = NULL;
  48         int bridge_pcix_cap = 0;
  49         int hca_pcie_cap = 0;
  50         int hca_pcix_cap = 0;
  51
  52         u16 devctl;
  53         u16 linkctl;
  54
  55 #define MTHCA_RESET_OFFSET 0xf0010
  56 #define MTHCA_RESET_VALUE  swab32(1)
  57
  58         /*
  59          * Reset the chip.  This is somewhat ugly because we have to
  60          * save off the PCI header before reset and then restore it
  61          * after the chip reboots.  We skip config space offsets 22
  62          * and 23 since those have a special meaning.
  63          *
  64          * To make matters worse, for Tavor (PCI-X HCA) we have to
  65          * find the associated bridge device and save off its PCI
  66          * header as well.
  67          */
  68
  69         if (!(mdev->mthca_flags & MTHCA_FLAG_PCIE)) {
  70                 /* Look for the bridge -- its device ID will be 2 more
  71                    than HCA's device ID. */
  72 #ifdef __linux__
  73                 while ((bridge = pci_get_device(mdev->pdev->vendor,
  74                                                 mdev->pdev->device + 2,
  75                                                 bridge)) != NULL) {
  76                         if (bridge->hdr_type    == PCI_HEADER_TYPE_BRIDGE &&
  77                             bridge->subordinate == mdev->pdev->bus) {
  78                                 mthca_dbg(mdev, "Found bridge: %s\n",
  79                                           pci_name(bridge));
  80                                 break;
  81                         }
  82                 }
  83
  84                 if (!bridge) {
  85                         /*
  86                          * Didn't find a bridge for a Tavor device --
  87                          * assume we're in no-bridge mode and hope for
  88                          * the best.
  89                          */
  90                         mthca_warn(mdev, "No bridge found for %s\n",
  91                                   pci_name(mdev->pdev));
  92                 }
  93 #else
  94                 mthca_warn(mdev, "Reset on PCI-X is not supported.\n");
  95                 goto out;
  96
  97 #endif
  98         }
  99
 100         /* For Arbel do we need to save off the full 4K PCI Express header?? */
 101         hca_header = kmalloc(256, GFP_KERNEL);
 102         if (!hca_header) {
 103                 err = -ENOMEM;
 104                 mthca_err(mdev, "Couldn't allocate memory to save HCA "
 105                           "PCI header, aborting.\n");
 106                 goto out;
 107         }
 108
 109         for (i = 0; i < 64; ++i) {
 110                 if (i == 22 || i == 23)
 111                         continue;
 112                 if (pci_read_config_dword(mdev->pdev, i * 4, hca_header + i)) {
 113                         err = -ENODEV;
 114                         mthca_err(mdev, "Couldn't save HCA "
 115                                   "PCI header, aborting.\n");
 116                         goto out;
 117                 }
 118         }
 119
 120         hca_pcix_cap = pci_find_capability(mdev->pdev, PCI_CAP_ID_PCIX);
 121         hca_pcie_cap = pci_find_capability(mdev->pdev, PCI_CAP_ID_EXP);
 122
 123 #ifdef __linux__
 124         if (bridge) {
 125                 bridge_header = kmalloc(256, GFP_KERNEL);
 126                 if (!bridge_header) {
 127                         err = -ENOMEM;
 128                         mthca_err(mdev, "Couldn't allocate memory to save HCA "
 129                                   "bridge PCI header, aborting.\n");
 130                         goto out;
 131                 }
 132
 133                 for (i = 0; i < 64; ++i) {
 134                         if (i == 22 || i == 23)
 135                                 continue;
 136                         if (pci_read_config_dword(bridge, i * 4, bridge_header + i)) {
 137                                 err = -ENODEV;
 138                                 mthca_err(mdev, "Couldn't save HCA bridge "
 139                                           "PCI header, aborting.\n");
 140                                 goto out;
 141                         }
 142                 }
 143                 bridge_pcix_cap = pci_find_capability(bridge, PCI_CAP_ID_PCIX);
 144                 if (!bridge_pcix_cap) {
 145                                 err = -ENODEV;
 146                                 mthca_err(mdev, "Couldn't locate HCA bridge "
 147                                           "PCI-X capability, aborting.\n");
 148                                 goto out;
 149                 }
 150         }
 151 #endif
 152
 153         /* actually hit reset */
 154         {
 155                 void __iomem *reset = ioremap(pci_resource_start(mdev->pdev, 0) +
 156                                               MTHCA_RESET_OFFSET, 4);
 157
 158                 if (!reset) {
 159                         err = -ENOMEM;
 160                         mthca_err(mdev, "Couldn't map HCA reset register, "
 161                                   "aborting.\n");
 162                         goto out;
 163                 }
 164
 165                 writel(MTHCA_RESET_VALUE, reset);
 166                 iounmap(reset);
 167         }
 168
 169         /* Docs say to wait one second before accessing device */
 170         msleep(1000);
 171
 172         /* Now wait for PCI device to start responding again */
 173         {
 174                 u32 v;
 175                 int c = 0;
 176
 177                 for (c = 0; c < 100; ++c) {
 178                         if (pci_read_config_dword(bridge ? bridge : mdev->pdev, 0, &v)) {
 179                                 err = -ENODEV;
 180                                 mthca_err(mdev, "Couldn't access HCA after reset, "
 181                                           "aborting.\n");
 182                                 goto out;
 183                         }
 184
 185                         if (v != 0xffffffff)
 186                                 goto good;
 187
 188                         msleep(100);
 189                 }
 190
 191                 err = -ENODEV;
 192                 mthca_err(mdev, "PCI device did not come back after reset, "
 193                           "aborting.\n");
 194                 goto out;
 195         }
 196
 197 good:
 198         /* Now restore the PCI headers */
 199         if (bridge) {
 200                 if (pci_write_config_dword(bridge, bridge_pcix_cap + 0x8,
 201                                  bridge_header[(bridge_pcix_cap + 0x8) / 4])) {
 202                         err = -ENODEV;
 203                         mthca_err(mdev, "Couldn't restore HCA bridge Upstream "
 204                                   "split transaction control, aborting.\n");
 205                         goto out;
 206                 }
 207                 if (pci_write_config_dword(bridge, bridge_pcix_cap + 0xc,
 208                                  bridge_header[(bridge_pcix_cap + 0xc) / 4])) {
 209                         err = -ENODEV;
 210                         mthca_err(mdev, "Couldn't restore HCA bridge Downstream "
 211                                   "split transaction control, aborting.\n");
 212                         goto out;
 213                 }
 214                 /*
 215                  * Bridge control register is at 0x3e, so we'll
 216                  * naturally restore it last in this loop.
 217                  */
 218                 for (i = 0; i < 16; ++i) {
 219                         if (i * 4 == PCI_COMMAND)
 220                                 continue;
 221
 222                         if (pci_write_config_dword(bridge, i * 4, bridge_header[i])) {
 223                                 err = -ENODEV;
 224                                 mthca_err(mdev, "Couldn't restore HCA bridge reg %x, "
 225                                           "aborting.\n", i);
 226                                 goto out;
 227                         }
 228                 }
 229
 230                 if (pci_write_config_dword(bridge, PCI_COMMAND,
 231                                            bridge_header[PCI_COMMAND / 4])) {
 232                         err = -ENODEV;
 233                         mthca_err(mdev, "Couldn't restore HCA bridge COMMAND, "
 234                                   "aborting.\n");
 235                         goto out;
 236                 }
 237         }
 238
 239         if (hca_pcix_cap) {
 240                 if (pci_write_config_dword(mdev->pdev, hca_pcix_cap,
 241                                  hca_header[hca_pcix_cap / 4])) {
 242                         err = -ENODEV;
 243                         mthca_err(mdev, "Couldn't restore HCA PCI-X "
 244                                   "command register, aborting.\n");
 245                         goto out;
 246                 }
 247         }
 248
 249         if (hca_pcie_cap) {
 250                 devctl = hca_header[(hca_pcie_cap + PCI_EXP_DEVCTL) / 4];
 251                 if (pci_write_config_word(mdev->pdev, hca_pcie_cap + PCI_EXP_DEVCTL,
 252                                            devctl)) {
 253                         err = -ENODEV;
 254                         mthca_err(mdev, "Couldn't restore HCA PCI Express "
 255                                   "Device Control register, aborting.\n");
 256                         goto out;
 257                 }
 258                 linkctl = hca_header[(hca_pcie_cap + PCI_EXP_LNKCTL) / 4];
 259                 if (pci_write_config_word(mdev->pdev, hca_pcie_cap + PCI_EXP_LNKCTL,
 260                                            linkctl)) {
 261                         err = -ENODEV;
 262                         mthca_err(mdev, "Couldn't restore HCA PCI Express "
 263                                   "Link control register, aborting.\n");
 264                         goto out;
 265                 }
 266         }
 267
 268         for (i = 0; i < 16; ++i) {
 269                 if (i * 4 == PCI_COMMAND)
 270                         continue;
 271
 272                 if (pci_write_config_dword(mdev->pdev, i * 4, hca_header[i])) {
 273                         err = -ENODEV;
 274                         mthca_err(mdev, "Couldn't restore HCA reg %x, "
 275                                   "aborting.\n", i);
 276                         goto out;
 277                 }
 278         }
 279
 280         if (pci_write_config_dword(mdev->pdev, PCI_COMMAND,
 281                                    hca_header[PCI_COMMAND / 4])) {
 282                 err = -ENODEV;
 283                 mthca_err(mdev, "Couldn't restore HCA COMMAND, "
 284                           "aborting.\n");
 285                 goto out;
 286         }
 287
 288 out:
 289 #ifdef __linux__
 290         if (bridge)
 291                 pci_dev_put(bridge);
 292 #endif
 293         kfree(bridge_header);
 294         kfree(hca_header);
 295
 296         return err;
 297 }