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/init.h>
  34 #include <linux/errno.h>
  35 #include <linux/pci.h>
  36 #include <linux/delay.h>
  37 #include <linux/slab.h>
  38
  39 #include "mthca_dev.h"
  40 #include "mthca_cmd.h"
  41
  42 int mthca_reset(struct mthca_dev *mdev)
  43 {
  44         int i;
  45         int err = 0;
  46         u32 *hca_header    = NULL;
  47         u32 *bridge_header = NULL;
  48         struct pci_dev *bridge = NULL;
  49         int bridge_pcix_cap = 0;
  50         int hca_pcie_cap = 0;
  51         int hca_pcix_cap = 0;
  52
  53         u16 devctl;
  54         u16 linkctl;
  55
  56 #define MTHCA_RESET_OFFSET 0xf0010
  57 #define MTHCA_RESET_VALUE  swab32(1)
  58
  59         /*
  60          * Reset the chip.  This is somewhat ugly because we have to
  61          * save off the PCI header before reset and then restore it
  62          * after the chip reboots.  We skip config space offsets 22
  63          * and 23 since those have a special meaning.
  64          *
  65          * To make matters worse, for Tavor (PCI-X HCA) we have to
  66          * find the associated bridge device and save off its PCI
  67          * header as well.
  68          */
  69
  70         if (!(mdev->mthca_flags & MTHCA_FLAG_PCIE)) {
  71                 /* Look for the bridge -- its device ID will be 2 more
  72                    than HCA's device ID. */
  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
  94         }
  95
  96         /* For Arbel do we need to save off the full 4K PCI Express header?? */
  97         hca_header = kmalloc(256, GFP_KERNEL);
  98         if (!hca_header) {
  99                 err = -ENOMEM;
 100                 mthca_err(mdev, "Couldn't allocate memory to save HCA "
 101                           "PCI header, aborting.\n");
 102                 goto out;
 103         }
 104
 105         for (i = 0; i < 64; ++i) {
 106                 if (i == 22 || i == 23)
 107                         continue;
 108                 if (pci_read_config_dword(mdev->pdev, i * 4, hca_header + i)) {
 109                         err = -ENODEV;
 110                         mthca_err(mdev, "Couldn't save HCA "
 111                                   "PCI header, aborting.\n");
 112                         goto out;
 113                 }
 114         }
 115
 116         hca_pcix_cap = pci_find_capability(mdev->pdev, PCI_CAP_ID_PCIX);
 117         hca_pcie_cap = pci_find_capability(mdev->pdev, PCI_CAP_ID_EXP);
 118
 119         if (bridge) {
 120                 bridge_header = kmalloc(256, GFP_KERNEL);
 121                 if (!bridge_header) {
 122                         err = -ENOMEM;
 123                         mthca_err(mdev, "Couldn't allocate memory to save HCA "
 124                                   "bridge PCI header, aborting.\n");
 125                         goto out;
 126                 }
 127
 128                 for (i = 0; i < 64; ++i) {
 129                         if (i == 22 || i == 23)
 130                                 continue;
 131                         if (pci_read_config_dword(bridge, i * 4, bridge_header + i)) {
 132                                 err = -ENODEV;
 133                                 mthca_err(mdev, "Couldn't save HCA bridge "
 134                                           "PCI header, aborting.\n");
 135                                 goto out;
 136                         }
 137                 }
 138                 bridge_pcix_cap = pci_find_capability(bridge, PCI_CAP_ID_PCIX);
 139                 if (!bridge_pcix_cap) {
 140                                 err = -ENODEV;
 141                                 mthca_err(mdev, "Couldn't locate HCA bridge "
 142                                           "PCI-X capability, aborting.\n");
 143                                 goto out;
 144                 }
 145         }
 146
 147         /* actually hit reset */
 148         {
 149                 void __iomem *reset = ioremap(pci_resource_start(mdev->pdev, 0) +
 150                                               MTHCA_RESET_OFFSET, 4);
 151
 152                 if (!reset) {
 153                         err = -ENOMEM;
 154                         mthca_err(mdev, "Couldn't map HCA reset register, "
 155                                   "aborting.\n");
 156                         goto out;
 157                 }
 158
 159                 writel(MTHCA_RESET_VALUE, reset);
 160                 iounmap(reset);
 161         }
 162
 163         /* Docs say to wait one second before accessing device */
 164         msleep(1000);
 165
 166         /* Now wait for PCI device to start responding again */
 167         {
 168                 u32 v;
 169                 int c = 0;
 170
 171                 for (c = 0; c < 100; ++c) {
 172                         if (pci_read_config_dword(bridge ? bridge : mdev->pdev, 0, &v)) {
 173                                 err = -ENODEV;
 174                                 mthca_err(mdev, "Couldn't access HCA after reset, "
 175                                           "aborting.\n");
 176                                 goto out;
 177                         }
 178
 179                         if (v != 0xffffffff)
 180                                 goto good;
 181
 182                         msleep(100);
 183                 }
 184
 185                 err = -ENODEV;
 186                 mthca_err(mdev, "PCI device did not come back after reset, "
 187                           "aborting.\n");
 188                 goto out;
 189         }
 190
 191 good:
 192         /* Now restore the PCI headers */
 193         if (bridge) {
 194                 if (pci_write_config_dword(bridge, bridge_pcix_cap + 0x8,
 195                                  bridge_header[(bridge_pcix_cap + 0x8) / 4])) {
 196                         err = -ENODEV;
 197                         mthca_err(mdev, "Couldn't restore HCA bridge Upstream "
 198                                   "split transaction control, aborting.\n");
 199                         goto out;
 200                 }
 201                 if (pci_write_config_dword(bridge, bridge_pcix_cap + 0xc,
 202                                  bridge_header[(bridge_pcix_cap + 0xc) / 4])) {
 203                         err = -ENODEV;
 204                         mthca_err(mdev, "Couldn't restore HCA bridge Downstream "
 205                                   "split transaction control, aborting.\n");
 206                         goto out;
 207                 }
 208                 /*
 209                  * Bridge control register is at 0x3e, so we'll
 210                  * naturally restore it last in this loop.
 211                  */
 212                 for (i = 0; i < 16; ++i) {
 213                         if (i * 4 == PCI_COMMAND)
 214                                 continue;
 215
 216                         if (pci_write_config_dword(bridge, i * 4, bridge_header[i])) {
 217                                 err = -ENODEV;
 218                                 mthca_err(mdev, "Couldn't restore HCA bridge reg %x, "
 219                                           "aborting.\n", i);
 220                                 goto out;
 221                         }
 222                 }
 223
 224                 if (pci_write_config_dword(bridge, PCI_COMMAND,
 225                                            bridge_header[PCI_COMMAND / 4])) {
 226                         err = -ENODEV;
 227                         mthca_err(mdev, "Couldn't restore HCA bridge COMMAND, "
 228                                   "aborting.\n");
 229                         goto out;
 230                 }
 231         }
 232
 233         if (hca_pcix_cap) {
 234                 if (pci_write_config_dword(mdev->pdev, hca_pcix_cap,
 235                                  hca_header[hca_pcix_cap / 4])) {
 236                         err = -ENODEV;
 237                         mthca_err(mdev, "Couldn't restore HCA PCI-X "
 238                                   "command register, aborting.\n");
 239                         goto out;
 240                 }
 241         }
 242
 243         if (hca_pcie_cap) {
 244                 devctl = hca_header[(hca_pcie_cap + PCI_EXP_DEVCTL) / 4];
 245                 if (pci_write_config_word(mdev->pdev, hca_pcie_cap + PCI_EXP_DEVCTL,
 246                                            devctl)) {
 247                         err = -ENODEV;
 248                         mthca_err(mdev, "Couldn't restore HCA PCI Express "
 249                                   "Device Control register, aborting.\n");
 250                         goto out;
 251                 }
 252                 linkctl = hca_header[(hca_pcie_cap + PCI_EXP_LNKCTL) / 4];
 253                 if (pci_write_config_word(mdev->pdev, hca_pcie_cap + PCI_EXP_LNKCTL,
 254                                            linkctl)) {
 255                         err = -ENODEV;
 256                         mthca_err(mdev, "Couldn't restore HCA PCI Express "
 257                                   "Link control register, aborting.\n");
 258                         goto out;
 259                 }
 260         }
 261
 262         for (i = 0; i < 16; ++i) {
 263                 if (i * 4 == PCI_COMMAND)
 264                         continue;
 265
 266                 if (pci_write_config_dword(mdev->pdev, i * 4, hca_header[i])) {
 267                         err = -ENODEV;
 268                         mthca_err(mdev, "Couldn't restore HCA reg %x, "
 269                                   "aborting.\n", i);
 270                         goto out;
 271                 }
 272         }
 273
 274         if (pci_write_config_dword(mdev->pdev, PCI_COMMAND,
 275                                    hca_header[PCI_COMMAND / 4])) {
 276                 err = -ENODEV;
 277                 mthca_err(mdev, "Couldn't restore HCA COMMAND, "
 278                           "aborting.\n");
 279                 goto out;
 280         }
 281
 282 out:
 283         if (bridge)
 284                 pci_dev_put(bridge);
 285         kfree(bridge_header);
 286         kfree(hca_header);
 287
 288         return err;
 289 }