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/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 #ifdef __linux__
  74                 while ((bridge = pci_get_device(mdev->pdev->vendor,
  75                                                 mdev->pdev->device + 2,
  76                                                 bridge)) != NULL) {
  77                         if (bridge->hdr_type    == PCI_HEADER_TYPE_BRIDGE &&
  78                             bridge->subordinate == mdev->pdev->bus) {
  79                                 mthca_dbg(mdev, "Found bridge: %s\n",
  80                                           pci_name(bridge));
  81                                 break;
  82                         }
  83                 }
  84
  85                 if (!bridge) {
  86                         /*
  87                          * Didn't find a bridge for a Tavor device --
  88                          * assume we're in no-bridge mode and hope for
  89                          * the best.
  90                          */
  91                         mthca_warn(mdev, "No bridge found for %s\n",
  92                                   pci_name(mdev->pdev));
  93                 }
  94 #else
  95                 mthca_warn(mdev, "Reset on PCI-X is not supported.\n");
  96                 goto out;
  97
  98 #endif
  99         }
 100
 101         /* For Arbel do we need to save off the full 4K PCI Express header?? */
 102         hca_header = kmalloc(256, GFP_KERNEL);
 103         if (!hca_header) {
 104                 err = -ENOMEM;
 105                 mthca_err(mdev, "Couldn't allocate memory to save HCA "
 106                           "PCI header, aborting.\n");
 107                 goto out;
 108         }
 109
 110         for (i = 0; i < 64; ++i) {
 111                 if (i == 22 || i == 23)
 112                         continue;
 113                 if (pci_read_config_dword(mdev->pdev, i * 4, hca_header + i)) {
 114                         err = -ENODEV;
 115                         mthca_err(mdev, "Couldn't save HCA "
 116                                   "PCI header, aborting.\n");
 117                         goto out;
 118                 }
 119         }
 120
 121         hca_pcix_cap = pci_find_capability(mdev->pdev, PCI_CAP_ID_PCIX);
 122         hca_pcie_cap = pci_find_capability(mdev->pdev, PCI_CAP_ID_EXP);
 123
 124 #ifdef __linux__
 125         if (bridge) {
 126                 bridge_header = kmalloc(256, GFP_KERNEL);
 127                 if (!bridge_header) {
 128                         err = -ENOMEM;
 129                         mthca_err(mdev, "Couldn't allocate memory to save HCA "
 130                                   "bridge PCI header, aborting.\n");
 131                         goto out;
 132                 }
 133
 134                 for (i = 0; i < 64; ++i) {
 135                         if (i == 22 || i == 23)
 136                                 continue;
 137                         if (pci_read_config_dword(bridge, i * 4, bridge_header + i)) {
 138                                 err = -ENODEV;
 139                                 mthca_err(mdev, "Couldn't save HCA bridge "
 140                                           "PCI header, aborting.\n");
 141                                 goto out;
 142                         }
 143                 }
 144                 bridge_pcix_cap = pci_find_capability(bridge, PCI_CAP_ID_PCIX);
 145                 if (!bridge_pcix_cap) {
 146                                 err = -ENODEV;
 147                                 mthca_err(mdev, "Couldn't locate HCA bridge "
 148                                           "PCI-X capability, aborting.\n");
 149                                 goto out;
 150                 }
 151         }
 152 #endif
 153
 154         /* actually hit reset */
 155         {
 156                 void __iomem *reset = ioremap(pci_resource_start(mdev->pdev, 0) +
 157                                               MTHCA_RESET_OFFSET, 4);
 158
 159                 if (!reset) {
 160                         err = -ENOMEM;
 161                         mthca_err(mdev, "Couldn't map HCA reset register, "
 162                                   "aborting.\n");
 163                         goto out;
 164                 }
 165
 166                 writel(MTHCA_RESET_VALUE, reset);
 167                 iounmap(reset);
 168         }
 169
 170         /* Docs say to wait one second before accessing device */
 171         msleep(1000);
 172
 173         /* Now wait for PCI device to start responding again */
 174         {
 175                 u32 v;
 176                 int c = 0;
 177
 178                 for (c = 0; c < 100; ++c) {
 179                         if (pci_read_config_dword(bridge ? bridge : mdev->pdev, 0, &v)) {
 180                                 err = -ENODEV;
 181                                 mthca_err(mdev, "Couldn't access HCA after reset, "
 182                                           "aborting.\n");
 183                                 goto out;
 184                         }
 185
 186                         if (v != 0xffffffff)
 187                                 goto good;
 188
 189                         msleep(100);
 190                 }
 191
 192                 err = -ENODEV;
 193                 mthca_err(mdev, "PCI device did not come back after reset, "
 194                           "aborting.\n");
 195                 goto out;
 196         }
 197
 198 good:
 199         /* Now restore the PCI headers */
 200         if (bridge) {
 201                 if (pci_write_config_dword(bridge, bridge_pcix_cap + 0x8,
 202                                  bridge_header[(bridge_pcix_cap + 0x8) / 4])) {
 203                         err = -ENODEV;
 204                         mthca_err(mdev, "Couldn't restore HCA bridge Upstream "
 205                                   "split transaction control, aborting.\n");
 206                         goto out;
 207                 }
 208                 if (pci_write_config_dword(bridge, bridge_pcix_cap + 0xc,
 209                                  bridge_header[(bridge_pcix_cap + 0xc) / 4])) {
 210                         err = -ENODEV;
 211                         mthca_err(mdev, "Couldn't restore HCA bridge Downstream "
 212                                   "split transaction control, aborting.\n");
 213                         goto out;
 214                 }
 215                 /*
 216                  * Bridge control register is at 0x3e, so we'll
 217                  * naturally restore it last in this loop.
 218                  */
 219                 for (i = 0; i < 16; ++i) {
 220                         if (i * 4 == PCI_COMMAND)
 221                                 continue;
 222
 223                         if (pci_write_config_dword(bridge, i * 4, bridge_header[i])) {
 224                                 err = -ENODEV;
 225                                 mthca_err(mdev, "Couldn't restore HCA bridge reg %x, "
 226                                           "aborting.\n", i);
 227                                 goto out;
 228                         }
 229                 }
 230
 231                 if (pci_write_config_dword(bridge, PCI_COMMAND,
 232                                            bridge_header[PCI_COMMAND / 4])) {
 233                         err = -ENODEV;
 234                         mthca_err(mdev, "Couldn't restore HCA bridge COMMAND, "
 235                                   "aborting.\n");
 236                         goto out;
 237                 }
 238         }
 239
 240         if (hca_pcix_cap) {
 241                 if (pci_write_config_dword(mdev->pdev, hca_pcix_cap,
 242                                  hca_header[hca_pcix_cap / 4])) {
 243                         err = -ENODEV;
 244                         mthca_err(mdev, "Couldn't restore HCA PCI-X "
 245                                   "command register, aborting.\n");
 246                         goto out;
 247                 }
 248         }
 249
 250         if (hca_pcie_cap) {
 251                 devctl = hca_header[(hca_pcie_cap + PCI_EXP_DEVCTL) / 4];
 252                 if (pci_write_config_word(mdev->pdev, hca_pcie_cap + PCI_EXP_DEVCTL,
 253                                            devctl)) {
 254                         err = -ENODEV;
 255                         mthca_err(mdev, "Couldn't restore HCA PCI Express "
 256                                   "Device Control register, aborting.\n");
 257                         goto out;
 258                 }
 259                 linkctl = hca_header[(hca_pcie_cap + PCI_EXP_LNKCTL) / 4];
 260                 if (pci_write_config_word(mdev->pdev, hca_pcie_cap + PCI_EXP_LNKCTL,
 261                                            linkctl)) {
 262                         err = -ENODEV;
 263                         mthca_err(mdev, "Couldn't restore HCA PCI Express "
 264                                   "Link control register, aborting.\n");
 265                         goto out;
 266                 }
 267         }
 268
 269         for (i = 0; i < 16; ++i) {
 270                 if (i * 4 == PCI_COMMAND)
 271                         continue;
 272
 273                 if (pci_write_config_dword(mdev->pdev, i * 4, hca_header[i])) {
 274                         err = -ENODEV;
 275                         mthca_err(mdev, "Couldn't restore HCA reg %x, "
 276                                   "aborting.\n", i);
 277                         goto out;
 278                 }
 279         }
 280
 281         if (pci_write_config_dword(mdev->pdev, PCI_COMMAND,
 282                                    hca_header[PCI_COMMAND / 4])) {
 283                 err = -ENODEV;
 284                 mthca_err(mdev, "Couldn't restore HCA COMMAND, "
 285                           "aborting.\n");
 286                 goto out;
 287         }
 288
 289 out:
 290 #ifdef __linux__
 291         if (bridge)
 292                 pci_dev_put(bridge);
 293 #endif
 294         kfree(bridge_header);
 295         kfree(hca_header);
 296
 297         return err;
 298 }