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/config.h>
  36 #include <linux/init.h>
  37 #include <linux/errno.h>
  38 #include <linux/pci.h>
  39 #include <linux/delay.h>
  40 #include <linux/slab.h>
  41
  42 #include "mthca_dev.h"
  43 #include "mthca_cmd.h"
  44
  45 int mthca_reset(struct mthca_dev *mdev)
  46 {
  47         int i;
  48         int err = 0;
  49         u32 *hca_header    = NULL;
  50         u32 *bridge_header = NULL;
  51         struct pci_dev *bridge = NULL;
  52         int bridge_pcix_cap = 0;
  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                 while ((bridge = pci_get_device(mdev->pdev->vendor,
  77                                                 mdev->pdev->device + 2,
  78                                                 bridge)) != NULL) {
  79                         if (bridge->hdr_type    == PCI_HEADER_TYPE_BRIDGE &&
  80                             bridge->subordinate == mdev->pdev->bus) {
  81                                 mthca_dbg(mdev, "Found bridge: %s\n",
  82                                           pci_name(bridge));
  83                                 break;
  84                         }
  85                 }
  86
  87                 if (!bridge) {
  88                         /*
  89                          * Didn't find a bridge for a Tavor device --
  90                          * assume we're in no-bridge mode and hope for
  91                          * the best.
  92                          */
  93                         mthca_warn(mdev, "No bridge found for %s\n",
  94                                   pci_name(mdev->pdev));
  95                 }
  96
  97         }
  98
  99         /* For Arbel do we need to save off the full 4K PCI Express header?? */
 100         hca_header = kmalloc(256, GFP_KERNEL);
 101         if (!hca_header) {
 102                 err = -ENOMEM;
 103                 mthca_err(mdev, "Couldn't allocate memory to save HCA "
 104                           "PCI header, aborting.\n");
 105                 goto out;
 106         }
 107
 108         for (i = 0; i < 64; ++i) {
 109                 if (i == 22 || i == 23)
 110                         continue;
 111                 if (pci_read_config_dword(mdev->pdev, i * 4, hca_header + i)) {
 112                         err = -ENODEV;
 113                         mthca_err(mdev, "Couldn't save HCA "
 114                                   "PCI header, aborting.\n");
 115                         goto out;
 116                 }
 117         }
 118
 119         hca_pcix_cap = pci_find_capability(mdev->pdev, PCI_CAP_ID_PCIX);
 120         hca_pcie_cap = pci_find_capability(mdev->pdev, PCI_CAP_ID_EXP);
 121
 122         if (bridge) {
 123                 bridge_header = kmalloc(256, GFP_KERNEL);
 124                 if (!bridge_header) {
 125                         err = -ENOMEM;
 126                         mthca_err(mdev, "Couldn't allocate memory to save HCA "
 127                                   "bridge PCI header, aborting.\n");
 128                         goto out;
 129                 }
 130
 131                 for (i = 0; i < 64; ++i) {
 132                         if (i == 22 || i == 23)
 133                                 continue;
 134                         if (pci_read_config_dword(bridge, i * 4, bridge_header + i)) {
 135                                 err = -ENODEV;
 136                                 mthca_err(mdev, "Couldn't save HCA bridge "
 137                                           "PCI header, aborting.\n");
 138                                 goto out;
 139                         }
 140                 }
 141                 bridge_pcix_cap = pci_find_capability(bridge, PCI_CAP_ID_PCIX);
 142                 if (!bridge_pcix_cap) {
 143                                 err = -ENODEV;
 144                                 mthca_err(mdev, "Couldn't locate HCA bridge "
 145                                           "PCI-X capability, aborting.\n");
 146                                 goto out;
 147                 }
 148         }
 149
 150         /* actually hit reset */
 151         {
 152                 void __iomem *reset = ioremap(pci_resource_start(mdev->pdev, 0) +
 153                                               MTHCA_RESET_OFFSET, 4);
 154
 155                 if (!reset) {
 156                         err = -ENOMEM;
 157                         mthca_err(mdev, "Couldn't map HCA reset register, "
 158                                   "aborting.\n");
 159                         goto out;
 160                 }
 161
 162                 writel(MTHCA_RESET_VALUE, reset);
 163                 iounmap(reset);
 164         }
 165
 166         /* Docs say to wait one second before accessing device */
 167         msleep(1000);
 168
 169         /* Now wait for PCI device to start responding again */
 170         {
 171                 u32 v;
 172                 int c = 0;
 173
 174                 for (c = 0; c < 100; ++c) {
 175                         if (pci_read_config_dword(bridge ? bridge : mdev->pdev, 0, &v)) {
 176                                 err = -ENODEV;
 177                                 mthca_err(mdev, "Couldn't access HCA after reset, "
 178                                           "aborting.\n");
 179                                 goto out;
 180                         }
 181
 182                         if (v != 0xffffffff)
 183                                 goto good;
 184
 185                         msleep(100);
 186                 }
 187
 188                 err = -ENODEV;
 189                 mthca_err(mdev, "PCI device did not come back after reset, "
 190                           "aborting.\n");
 191                 goto out;
 192         }
 193
 194 good:
 195         /* Now restore the PCI headers */
 196         if (bridge) {
 197                 if (pci_write_config_dword(bridge, bridge_pcix_cap + 0x8,
 198                                  bridge_header[(bridge_pcix_cap + 0x8) / 4])) {
 199                         err = -ENODEV;
 200                         mthca_err(mdev, "Couldn't restore HCA bridge Upstream "
 201                                   "split transaction control, aborting.\n");
 202                         goto out;
 203                 }
 204                 if (pci_write_config_dword(bridge, bridge_pcix_cap + 0xc,
 205                                  bridge_header[(bridge_pcix_cap + 0xc) / 4])) {
 206                         err = -ENODEV;
 207                         mthca_err(mdev, "Couldn't restore HCA bridge Downstream "
 208                                   "split transaction control, aborting.\n");
 209                         goto out;
 210                 }
 211                 /*
 212                  * Bridge control register is at 0x3e, so we'll
 213                  * naturally restore it last in this loop.
 214                  */
 215                 for (i = 0; i < 16; ++i) {
 216                         if (i * 4 == PCI_COMMAND)
 217                                 continue;
 218
 219                         if (pci_write_config_dword(bridge, i * 4, bridge_header[i])) {
 220                                 err = -ENODEV;
 221                                 mthca_err(mdev, "Couldn't restore HCA bridge reg %x, "
 222                                           "aborting.\n", i);
 223                                 goto out;
 224                         }
 225                 }
 226
 227                 if (pci_write_config_dword(bridge, PCI_COMMAND,
 228                                            bridge_header[PCI_COMMAND / 4])) {
 229                         err = -ENODEV;
 230                         mthca_err(mdev, "Couldn't restore HCA bridge COMMAND, "
 231                                   "aborting.\n");
 232                         goto out;
 233                 }
 234         }
 235
 236         if (hca_pcix_cap) {
 237                 if (pci_write_config_dword(mdev->pdev, hca_pcix_cap,
 238                                  hca_header[hca_pcix_cap / 4])) {
 239                         err = -ENODEV;
 240                         mthca_err(mdev, "Couldn't restore HCA PCI-X "
 241                                   "command register, aborting.\n");
 242                         goto out;
 243                 }
 244         }
 245
 246         if (hca_pcie_cap) {
 247                 devctl = hca_header[(hca_pcie_cap + PCI_EXP_DEVCTL) / 4];
 248                 if (pci_write_config_word(mdev->pdev, hca_pcie_cap + PCI_EXP_DEVCTL,
 249                                            devctl)) {
 250                         err = -ENODEV;
 251                         mthca_err(mdev, "Couldn't restore HCA PCI Express "
 252                                   "Device Control register, aborting.\n");
 253                         goto out;
 254                 }
 255                 linkctl = hca_header[(hca_pcie_cap + PCI_EXP_LNKCTL) / 4];
 256                 if (pci_write_config_word(mdev->pdev, hca_pcie_cap + PCI_EXP_LNKCTL,
 257                                            linkctl)) {
 258                         err = -ENODEV;
 259                         mthca_err(mdev, "Couldn't restore HCA PCI Express "
 260                                   "Link control register, aborting.\n");
 261                         goto out;
 262                 }
 263         }
 264
 265         for (i = 0; i < 16; ++i) {
 266                 if (i * 4 == PCI_COMMAND)
 267                         continue;
 268
 269                 if (pci_write_config_dword(mdev->pdev, i * 4, hca_header[i])) {
 270                         err = -ENODEV;
 271                         mthca_err(mdev, "Couldn't restore HCA reg %x, "
 272                                   "aborting.\n", i);
 273                         goto out;
 274                 }
 275         }
 276
 277         if (pci_write_config_dword(mdev->pdev, PCI_COMMAND,
 278                                    hca_header[PCI_COMMAND / 4])) {
 279                 err = -ENODEV;
 280                 mthca_err(mdev, "Couldn't restore HCA COMMAND, "
 281                           "aborting.\n");
 282                 goto out;
 283         }
 284
 285 out:
 286         if (bridge)
 287                 pci_dev_put(bridge);
 288         kfree(bridge_header);
 289         kfree(hca_header);
 290
 291         return err;
 292 }