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  * $Id: mthca_reset.c 1349 2004-12-16 21:09:43Z roland $
  33  */
  34
  35 #include <linux/init.h>
  36 #include <linux/errno.h>
  37 #include <linux/pci.h>
  38 #include <linux/delay.h>
  39 #include <linux/slab.h>
  40
  41 #include "mthca_dev.h"
  42 #include "mthca_cmd.h"
  43
  44 int mthca_reset(struct mthca_dev *mdev)
  45 {
  46         int i;
  47         int err = 0;
  48         u32 *hca_header    = NULL;
  49         u32 *bridge_header = NULL;
  50         struct pci_dev *bridge = NULL;
  51         int bridge_pcix_cap = 0;
  52         int hca_pcie_cap = 0;
  53         int hca_pcix_cap = 0;
  54
  55         u16 devctl;
  56         u16 linkctl;
  57
  58 #define MTHCA_RESET_OFFSET 0xf0010
  59 #define MTHCA_RESET_VALUE  swab32(1)
  60
  61         /*
  62          * Reset the chip.  This is somewhat ugly because we have to
  63          * save off the PCI header before reset and then restore it
  64          * after the chip reboots.  We skip config space offsets 22
  65          * and 23 since those have a special meaning.
  66          *
  67          * To make matters worse, for Tavor (PCI-X HCA) we have to
  68          * find the associated bridge device and save off its PCI
  69          * header as well.
  70          */
  71
  72         if (!(mdev->mthca_flags & MTHCA_FLAG_PCIE)) {
  73                 /* Look for the bridge -- its device ID will be 2 more
  74                    than HCA's device ID. */
  75                 while ((bridge = pci_get_device(mdev->pdev->vendor,
  76                                                 mdev->pdev->device + 2,
  77                                                 bridge)) != NULL) {
  78                         if (bridge->hdr_type    == PCI_HEADER_TYPE_BRIDGE &&
  79                             bridge->subordinate == mdev->pdev->bus) {
  80                                 mthca_dbg(mdev, "Found bridge: %s\n",
  81                                           pci_name(bridge));
  82                                 break;
  83                         }
  84                 }
  85
  86                 if (!bridge) {
  87                         /*
  88                          * Didn't find a bridge for a Tavor device --
  89                          * assume we're in no-bridge mode and hope for
  90                          * the best.
  91                          */
  92                         mthca_warn(mdev, "No bridge found for %s\n",
  93                                   pci_name(mdev->pdev));
  94                 }
  95
  96         }
  97
  98         /* For Arbel do we need to save off the full 4K PCI Express header?? */
  99         hca_header = kmalloc(256, GFP_KERNEL);
 100         if (!hca_header) {
 101                 err = -ENOMEM;
 102                 mthca_err(mdev, "Couldn't allocate memory to save HCA "
 103                           "PCI header, aborting.\n");
 104                 goto out;
 105         }
 106
 107         for (i = 0; i < 64; ++i) {
 108                 if (i == 22 || i == 23)
 109                         continue;
 110                 if (pci_read_config_dword(mdev->pdev, i * 4, hca_header + i)) {
 111                         err = -ENODEV;
 112                         mthca_err(mdev, "Couldn't save HCA "
 113                                   "PCI header, aborting.\n");
 114                         goto out;
 115                 }
 116         }
 117
 118         hca_pcix_cap = pci_find_capability(mdev->pdev, PCI_CAP_ID_PCIX);
 119         hca_pcie_cap = pci_find_capability(mdev->pdev, PCI_CAP_ID_EXP);
 120
 121         if (bridge) {
 122                 bridge_header = kmalloc(256, GFP_KERNEL);
 123                 if (!bridge_header) {
 124                         err = -ENOMEM;
 125                         mthca_err(mdev, "Couldn't allocate memory to save HCA "
 126                                   "bridge PCI header, aborting.\n");
 127                         goto out;
 128                 }
 129
 130                 for (i = 0; i < 64; ++i) {
 131                         if (i == 22 || i == 23)
 132                                 continue;
 133                         if (pci_read_config_dword(bridge, i * 4, bridge_header + i)) {
 134                                 err = -ENODEV;
 135                                 mthca_err(mdev, "Couldn't save HCA bridge "
 136                                           "PCI header, aborting.\n");
 137                                 goto out;
 138                         }
 139                 }
 140                 bridge_pcix_cap = pci_find_capability(bridge, PCI_CAP_ID_PCIX);
 141                 if (!bridge_pcix_cap) {
 142                                 err = -ENODEV;
 143                                 mthca_err(mdev, "Couldn't locate HCA bridge "
 144                                           "PCI-X capability, aborting.\n");
 145                                 goto out;
 146                 }
 147         }
 148
 149         /* actually hit reset */
 150         {
 151                 void __iomem *reset = ioremap(pci_resource_start(mdev->pdev, 0) +
 152                                               MTHCA_RESET_OFFSET, 4);
 153
 154                 if (!reset) {
 155                         err = -ENOMEM;
 156                         mthca_err(mdev, "Couldn't map HCA reset register, "
 157                                   "aborting.\n");
 158                         goto out;
 159                 }
 160
 161                 writel(MTHCA_RESET_VALUE, reset);
 162                 iounmap(reset);
 163         }
 164
 165         /* Docs say to wait one second before accessing device */
 166         msleep(1000);
 167
 168         /* Now wait for PCI device to start responding again */
 169         {
 170                 u32 v;
 171                 int c = 0;
 172
 173                 for (c = 0; c < 100; ++c) {
 174                         if (pci_read_config_dword(bridge ? bridge : mdev->pdev, 0, &v)) {
 175                                 err = -ENODEV;
 176                                 mthca_err(mdev, "Couldn't access HCA after reset, "
 177                                           "aborting.\n");
 178                                 goto out;
 179                         }
 180
 181                         if (v != 0xffffffff)
 182                                 goto good;
 183
 184                         msleep(100);
 185                 }
 186
 187                 err = -ENODEV;
 188                 mthca_err(mdev, "PCI device did not come back after reset, "
 189                           "aborting.\n");
 190                 goto out;
 191         }
 192
 193 good:
 194         /* Now restore the PCI headers */
 195         if (bridge) {
 196                 if (pci_write_config_dword(bridge, bridge_pcix_cap + 0x8,
 197                                  bridge_header[(bridge_pcix_cap + 0x8) / 4])) {
 198                         err = -ENODEV;
 199                         mthca_err(mdev, "Couldn't restore HCA bridge Upstream "
 200                                   "split transaction control, aborting.\n");
 201                         goto out;
 202                 }
 203                 if (pci_write_config_dword(bridge, bridge_pcix_cap + 0xc,
 204                                  bridge_header[(bridge_pcix_cap + 0xc) / 4])) {
 205                         err = -ENODEV;
 206                         mthca_err(mdev, "Couldn't restore HCA bridge Downstream "
 207                                   "split transaction control, aborting.\n");
 208                         goto out;
 209                 }
 210                 /*
 211                  * Bridge control register is at 0x3e, so we'll
 212                  * naturally restore it last in this loop.
 213                  */
 214                 for (i = 0; i < 16; ++i) {
 215                         if (i * 4 == PCI_COMMAND)
 216                                 continue;
 217
 218                         if (pci_write_config_dword(bridge, i * 4, bridge_header[i])) {
 219                                 err = -ENODEV;
 220                                 mthca_err(mdev, "Couldn't restore HCA bridge reg %x, "
 221                                           "aborting.\n", i);
 222                                 goto out;
 223                         }
 224                 }
 225
 226                 if (pci_write_config_dword(bridge, PCI_COMMAND,
 227                                            bridge_header[PCI_COMMAND / 4])) {
 228                         err = -ENODEV;
 229                         mthca_err(mdev, "Couldn't restore HCA bridge COMMAND, "
 230                                   "aborting.\n");
 231                         goto out;
 232                 }
 233         }
 234
 235         if (hca_pcix_cap) {
 236                 if (pci_write_config_dword(mdev->pdev, hca_pcix_cap,
 237                                  hca_header[hca_pcix_cap / 4])) {
 238                         err = -ENODEV;
 239                         mthca_err(mdev, "Couldn't restore HCA PCI-X "
 240                                   "command register, aborting.\n");
 241                         goto out;
 242                 }
 243         }
 244
 245         if (hca_pcie_cap) {
 246                 devctl = hca_header[(hca_pcie_cap + PCI_EXP_DEVCTL) / 4];
 247                 if (pci_write_config_word(mdev->pdev, hca_pcie_cap + PCI_EXP_DEVCTL,
 248                                            devctl)) {
 249                         err = -ENODEV;
 250                         mthca_err(mdev, "Couldn't restore HCA PCI Express "
 251                                   "Device Control register, aborting.\n");
 252                         goto out;
 253                 }
 254                 linkctl = hca_header[(hca_pcie_cap + PCI_EXP_LNKCTL) / 4];
 255                 if (pci_write_config_word(mdev->pdev, hca_pcie_cap + PCI_EXP_LNKCTL,
 256                                            linkctl)) {
 257                         err = -ENODEV;
 258                         mthca_err(mdev, "Couldn't restore HCA PCI Express "
 259                                   "Link control register, aborting.\n");
 260                         goto out;
 261                 }
 262         }
 263
 264         for (i = 0; i < 16; ++i) {
 265                 if (i * 4 == PCI_COMMAND)
 266                         continue;
 267
 268                 if (pci_write_config_dword(mdev->pdev, i * 4, hca_header[i])) {
 269                         err = -ENODEV;
 270                         mthca_err(mdev, "Couldn't restore HCA reg %x, "
 271                                   "aborting.\n", i);
 272                         goto out;
 273                 }
 274         }
 275
 276         if (pci_write_config_dword(mdev->pdev, PCI_COMMAND,
 277                                    hca_header[PCI_COMMAND / 4])) {
 278                 err = -ENODEV;
 279                 mthca_err(mdev, "Couldn't restore HCA COMMAND, "
 280                           "aborting.\n");
 281                 goto out;
 282         }
 283
 284 out:
 285         if (bridge)
 286                 pci_dev_put(bridge);
 287         kfree(bridge_header);
 288         kfree(hca_header);
 289
 290         return err;
 291 }