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
  53 #define MTHCA_RESET_OFFSET 0xf0010
  54 #define MTHCA_RESET_VALUE  swab32(1)
  55
  56         /*
  57          * Reset the chip.  This is somewhat ugly because we have to
  58          * save off the PCI header before reset and then restore it
  59          * after the chip reboots.  We skip config space offsets 22
  60          * and 23 since those have a special meaning.
  61          *
  62          * To make matters worse, for Tavor (PCI-X HCA) we have to
  63          * find the associated bridge device and save off its PCI
  64          * header as well.
  65          */
  66
  67         if (!(mdev->mthca_flags & MTHCA_FLAG_PCIE)) {
  68                 /* Look for the bridge -- its device ID will be 2 more
  69                    than HCA's device ID. */
  70                 while ((bridge = pci_get_device(mdev->pdev->vendor,
  71                                                 mdev->pdev->device + 2,
  72                                                 bridge)) != NULL) {
  73                         if (bridge->hdr_type    == PCI_HEADER_TYPE_BRIDGE &&
  74                             bridge->subordinate == mdev->pdev->bus) {
  75                                 mthca_dbg(mdev, "Found bridge: %s\n",
  76                                           pci_name(bridge));
  77                                 break;
  78                         }
  79                 }
  80
  81                 if (!bridge) {
  82                         /*
  83                          * Didn't find a bridge for a Tavor device --
  84                          * assume we're in no-bridge mode and hope for
  85                          * the best.
  86                          */
  87                         mthca_warn(mdev, "No bridge found for %s\n",
  88                                   pci_name(mdev->pdev));
  89                 }
  90
  91         }
  92
  93         /* For Arbel do we need to save off the full 4K PCI Express header?? */
  94         hca_header = kmalloc(256, GFP_KERNEL);
  95         if (!hca_header) {
  96                 err = -ENOMEM;
  97                 mthca_err(mdev, "Couldn't allocate memory to save HCA "
  98                           "PCI header, aborting.\n");
  99                 goto out;
 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 out;
 110                 }
 111         }
 112
 113         if (bridge) {
 114                 bridge_header = kmalloc(256, GFP_KERNEL);
 115                 if (!bridge_header) {
 116                         err = -ENOMEM;
 117                         mthca_err(mdev, "Couldn't allocate memory to save HCA "
 118                                   "bridge PCI header, aborting.\n");
 119                         goto out;
 120                 }
 121
 122                 for (i = 0; i < 64; ++i) {
 123                         if (i == 22 || i == 23)
 124                                 continue;
 125                         if (pci_read_config_dword(bridge, i * 4, bridge_header + i)) {
 126                                 err = -ENODEV;
 127                                 mthca_err(mdev, "Couldn't save HCA bridge "
 128                                           "PCI header, aborting.\n");
 129                                 goto out;
 130                         }
 131                 }
 132         }
 133
 134         /* actually hit reset */
 135         {
 136                 void __iomem *reset = ioremap(pci_resource_start(mdev->pdev, 0) +
 137                                               MTHCA_RESET_OFFSET, 4);
 138
 139                 if (!reset) {
 140                         err = -ENOMEM;
 141                         mthca_err(mdev, "Couldn't map HCA reset register, "
 142                                   "aborting.\n");
 143                         goto out;
 144                 }
 145
 146                 writel(MTHCA_RESET_VALUE, reset);
 147                 iounmap(reset);
 148         }
 149
 150         /* Docs say to wait one second before accessing device */
 151         msleep(1000);
 152
 153         /* Now wait for PCI device to start responding again */
 154         {
 155                 u32 v;
 156                 int c = 0;
 157
 158                 for (c = 0; c < 100; ++c) {
 159                         if (pci_read_config_dword(bridge ? bridge : mdev->pdev, 0, &v)) {
 160                                 err = -ENODEV;
 161                                 mthca_err(mdev, "Couldn't access HCA after reset, "
 162                                           "aborting.\n");
 163                                 goto out;
 164                         }
 165
 166                         if (v != 0xffffffff)
 167                                 goto good;
 168
 169                         msleep(100);
 170                 }
 171
 172                 err = -ENODEV;
 173                 mthca_err(mdev, "PCI device did not come back after reset, "
 174                           "aborting.\n");
 175                 goto out;
 176         }
 177
 178 good:
 179         /* Now restore the PCI headers */
 180         if (bridge) {
 181                 /*
 182                  * Bridge control register is at 0x3e, so we'll
 183                  * naturally restore it last in this loop.
 184                  */
 185                 for (i = 0; i < 16; ++i) {
 186                         if (i * 4 == PCI_COMMAND)
 187                                 continue;
 188
 189                         if (pci_write_config_dword(bridge, i * 4, bridge_header[i])) {
 190                                 err = -ENODEV;
 191                                 mthca_err(mdev, "Couldn't restore HCA bridge reg %x, "
 192                                           "aborting.\n", i);
 193                                 goto out;
 194                         }
 195                 }
 196
 197                 if (pci_write_config_dword(bridge, PCI_COMMAND,
 198                                            bridge_header[PCI_COMMAND / 4])) {
 199                         err = -ENODEV;
 200                         mthca_err(mdev, "Couldn't restore HCA bridge COMMAND, "
 201                                   "aborting.\n");
 202                         goto out;
 203                 }
 204         }
 205
 206         for (i = 0; i < 16; ++i) {
 207                 if (i * 4 == PCI_COMMAND)
 208                         continue;
 209
 210                 if (pci_write_config_dword(mdev->pdev, i * 4, hca_header[i])) {
 211                         err = -ENODEV;
 212                         mthca_err(mdev, "Couldn't restore HCA reg %x, "
 213                                   "aborting.\n", i);
 214                         goto out;
 215                 }
 216         }
 217
 218         if (pci_write_config_dword(mdev->pdev, PCI_COMMAND,
 219                                    hca_header[PCI_COMMAND / 4])) {
 220                 err = -ENODEV;
 221                 mthca_err(mdev, "Couldn't restore HCA COMMAND, "
 222                           "aborting.\n");
 223                 goto out;
 224         }
 225
 226 out:
 227         if (bridge)
 228                 pci_dev_put(bridge);
 229         kfree(bridge_header);
 230         kfree(hca_header);
 231
 232         return err;
 233 }