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