drivers/net/mlx4/reset.c

   1 /*
   2  * Copyright (c) 2006, 2007 Cisco Systems, Inc.  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 "mlx4.h"
  40
  41 int mlx4_reset(struct mlx4_dev *dev)
  42 {
  43         void __iomem *reset;
  44         u32 *hca_header = NULL;
  45         int pcie_cap;
  46         u16 devctl;
  47         u16 linkctl;
  48         u16 vendor;
  49         unsigned long end;
  50         u32 sem;
  51         int i;
  52         int err = 0;
  53
  54 #define MLX4_RESET_BASE         0xf0000
  55 #define MLX4_RESET_SIZE           0x400
  56 #define MLX4_SEM_OFFSET           0x3fc
  57 #define MLX4_RESET_OFFSET          0x10
  58 #define MLX4_RESET_VALUE        swab32(1)
  59
  60 #define MLX4_SEM_TIMEOUT_JIFFIES        (10 * HZ)
  61 #define MLX4_RESET_TIMEOUT_JIFFIES      (2 * HZ)
  62
  63         /*
  64          * Reset the chip.  This is somewhat ugly because we have to
  65          * save off the PCI header before reset and then restore it
  66          * after the chip reboots.  We skip config space offsets 22
  67          * and 23 since those have a special meaning.
  68          */
  69
  70         /* Do we need to save off the full 4K PCI Express header?? */
  71         hca_header = kmalloc(256, GFP_KERNEL);
  72         if (!hca_header) {
  73                 err = -ENOMEM;
  74                 mlx4_err(dev, "Couldn't allocate memory to save HCA "
  75                           "PCI header, aborting.\n");
  76                 goto out;
  77         }
  78
  79         pcie_cap = pci_find_capability(dev->pdev, PCI_CAP_ID_EXP);
  80
  81         for (i = 0; i < 64; ++i) {
  82                 if (i == 22 || i == 23)
  83                         continue;
  84                 if (pci_read_config_dword(dev->pdev, i * 4, hca_header + i)) {
  85                         err = -ENODEV;
  86                         mlx4_err(dev, "Couldn't save HCA "
  87                                   "PCI header, aborting.\n");
  88                         goto out;
  89                 }
  90         }
  91
  92         reset = ioremap(pci_resource_start(dev->pdev, 0) + MLX4_RESET_BASE,
  93                         MLX4_RESET_SIZE);
  94         if (!reset) {
  95                 err = -ENOMEM;
  96                 mlx4_err(dev, "Couldn't map HCA reset register, aborting.\n");
  97                 goto out;
  98         }
  99
 100         /* grab HW semaphore to lock out flash updates */
 101         end = jiffies + MLX4_SEM_TIMEOUT_JIFFIES;
 102         do {
 103                 sem = readl(reset + MLX4_SEM_OFFSET);
 104                 if (!sem)
 105                         break;
 106
 107                 msleep(1);
 108         } while (time_before(jiffies, end));
 109
 110         if (sem) {
 111                 mlx4_err(dev, "Failed to obtain HW semaphore, aborting\n");
 112                 err = -EAGAIN;
 113                 iounmap(reset);
 114                 goto out;
 115         }
 116
 117         /* actually hit reset */
 118         writel(MLX4_RESET_VALUE, reset + MLX4_RESET_OFFSET);
 119         iounmap(reset);
 120
 121         end = jiffies + MLX4_RESET_TIMEOUT_JIFFIES;
 122         do {
 123                 if (!pci_read_config_word(dev->pdev, PCI_VENDOR_ID, &vendor) &&
 124                     vendor != 0xffff)
 125                         break;
 126
 127                 msleep(1);
 128         } while (time_before(jiffies, end));
 129
 130         if (vendor == 0xffff) {
 131                 err = -ENODEV;
 132                 mlx4_err(dev, "PCI device did not come back after reset, "
 133                           "aborting.\n");
 134                 goto out;
 135         }
 136
 137         /* Now restore the PCI headers */
 138         if (pcie_cap) {
 139                 devctl = hca_header[(pcie_cap + PCI_EXP_DEVCTL) / 4];
 140                 if (pci_write_config_word(dev->pdev, pcie_cap + PCI_EXP_DEVCTL,
 141                                            devctl)) {
 142                         err = -ENODEV;
 143                         mlx4_err(dev, "Couldn't restore HCA PCI Express "
 144                                  "Device Control register, aborting.\n");
 145                         goto out;
 146                 }
 147                 linkctl = hca_header[(pcie_cap + PCI_EXP_LNKCTL) / 4];
 148                 if (pci_write_config_word(dev->pdev, pcie_cap + PCI_EXP_LNKCTL,
 149                                            linkctl)) {
 150                         err = -ENODEV;
 151                         mlx4_err(dev, "Couldn't restore HCA PCI Express "
 152                                  "Link control register, aborting.\n");
 153                         goto out;
 154                 }
 155         }
 156
 157         for (i = 0; i < 16; ++i) {
 158                 if (i * 4 == PCI_COMMAND)
 159                         continue;
 160
 161                 if (pci_write_config_dword(dev->pdev, i * 4, hca_header[i])) {
 162                         err = -ENODEV;
 163                         mlx4_err(dev, "Couldn't restore HCA reg %x, "
 164                                   "aborting.\n", i);
 165                         goto out;
 166                 }
 167         }
 168
 169         if (pci_write_config_dword(dev->pdev, PCI_COMMAND,
 170                                    hca_header[PCI_COMMAND / 4])) {
 171                 err = -ENODEV;
 172                 mlx4_err(dev, "Couldn't restore HCA COMMAND, "
 173                           "aborting.\n");
 174                 goto out;
 175         }
 176
 177 out:
 178         kfree(hca_header);
 179
 180         return err;
 181 }