drivers/net/ethernet/mellanox/mlx4/reset.c

   1 /*
   2  * Copyright (c) 2006, 2007 Cisco Systems, Inc.  All rights reserved.
   3  * Copyright (c) 2007, 2008 Mellanox Technologies. All rights reserved.
   4  *
   5  * This software is available to you under a choice of one of two
   6  * licenses.  You may choose to be licensed under the terms of the GNU
   7  * General Public License (GPL) Version 2, available from the file
   8  * COPYING in the main directory of this source tree, or the
   9  * OpenIB.org BSD license below:
  10  *
  11  *     Redistribution and use in source and binary forms, with or
  12  *     without modification, are permitted provided that the following
  13  *     conditions are met:
  14  *
  15  *      - Redistributions of source code must retain the above
  16  *        copyright notice, this list of conditions and the following
  17  *        disclaimer.
  18  *
  19  *      - Redistributions in binary form must reproduce the above
  20  *        copyright notice, this list of conditions and the following
  21  *        disclaimer in the documentation and/or other materials
  22  *        provided with the distribution.
  23  *
  24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  25  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  26  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  27  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  28  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  29  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  30  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  31  * SOFTWARE.
  32  */
  33
  34 #include <linux/errno.h>
  35 #include <linux/pci.h>
  36 #include <linux/delay.h>
  37 #include <linux/slab.h>
  38 #include <linux/jiffies.h>
  39
  40 #include "mlx4.h"
  41
  42 int mlx4_reset(struct mlx4_dev *dev)
  43 {
  44         void __iomem *reset;
  45         u32 *hca_header = NULL;
  46         int pcie_cap;
  47         u16 devctl;
  48         u16 linkctl;
  49         u16 vendor;
  50         unsigned long end;
  51         u32 sem;
  52         int i;
  53         int err = 0;
  54
  55 #define MLX4_RESET_BASE         0xf0000
  56 #define MLX4_RESET_SIZE           0x400
  57 #define MLX4_SEM_OFFSET           0x3fc
  58 #define MLX4_RESET_OFFSET          0x10
  59 #define MLX4_RESET_VALUE        swab32(1)
  60
  61 #define MLX4_SEM_TIMEOUT_JIFFIES        (10 * HZ)
  62 #define MLX4_RESET_TIMEOUT_JIFFIES      (2 * HZ)
  63
  64         /*
  65          * Reset the chip.  This is somewhat ugly because we have to
  66          * save off the PCI header before reset and then restore it
  67          * after the chip reboots.  We skip config space offsets 22
  68          * and 23 since those have a special meaning.
  69          */
  70
  71         /* Do we need to save off the full 4K PCI Express header?? */
  72         hca_header = kmalloc(256, GFP_KERNEL);
  73         if (!hca_header) {
  74                 err = -ENOMEM;
  75                 mlx4_err(dev, "Couldn't allocate memory to save HCA PCI header, aborting\n");
  76                 goto out;
  77         }
  78
  79         pcie_cap = pci_pcie_cap(dev->persist->pdev);
  80
  81         for (i = 0; i < 64; ++i) {
  82                 if (i == 22 || i == 23)
  83                         continue;
  84                 if (pci_read_config_dword(dev->persist->pdev, i * 4,
  85                                           hca_header + i)) {
  86                         err = -ENODEV;
  87                         mlx4_err(dev, "Couldn't save HCA PCI header, aborting\n");
  88                         goto out;
  89                 }
  90         }
  91
  92         reset = ioremap(pci_resource_start(dev->persist->pdev, 0) +
  93                         MLX4_RESET_BASE,
  94                         MLX4_RESET_SIZE);
  95         if (!reset) {
  96                 err = -ENOMEM;
  97                 mlx4_err(dev, "Couldn't map HCA reset register, aborting\n");
  98                 goto out;
  99         }
 100
 101         /* grab HW semaphore to lock out flash updates */
 102         end = jiffies + MLX4_SEM_TIMEOUT_JIFFIES;
 103         do {
 104                 sem = readl(reset + MLX4_SEM_OFFSET);
 105                 if (!sem)
 106                         break;
 107
 108                 msleep(1);
 109         } while (time_before(jiffies, end));
 110
 111         if (sem) {
 112                 mlx4_err(dev, "Failed to obtain HW semaphore, aborting\n");
 113                 err = -EAGAIN;
 114                 iounmap(reset);
 115                 goto out;
 116         }
 117
 118         /* actually hit reset */
 119         writel(MLX4_RESET_VALUE, reset + MLX4_RESET_OFFSET);
 120         iounmap(reset);
 121
 122         /* Docs say to wait one second before accessing device */
 123         msleep(1000);
 124
 125         end = jiffies + MLX4_RESET_TIMEOUT_JIFFIES;
 126         do {
 127                 if (!pci_read_config_word(dev->persist->pdev, PCI_VENDOR_ID,
 128                                           &vendor) && vendor != 0xffff)
 129                         break;
 130
 131                 msleep(1);
 132         } while (time_before(jiffies, end));
 133
 134         if (vendor == 0xffff) {
 135                 err = -ENODEV;
 136                 mlx4_err(dev, "PCI device did not come back after reset, aborting\n");
 137                 goto out;
 138         }
 139
 140         /* Now restore the PCI headers */
 141         if (pcie_cap) {
 142                 devctl = hca_header[(pcie_cap + PCI_EXP_DEVCTL) / 4];
 143                 if (pcie_capability_write_word(dev->persist->pdev,
 144                                                PCI_EXP_DEVCTL,
 145                                                devctl)) {
 146                         err = -ENODEV;
 147                         mlx4_err(dev, "Couldn't restore HCA PCI Express Device Control register, aborting\n");
 148                         goto out;
 149                 }
 150                 linkctl = hca_header[(pcie_cap + PCI_EXP_LNKCTL) / 4];
 151                 if (pcie_capability_write_word(dev->persist->pdev,
 152                                                PCI_EXP_LNKCTL,
 153                                                linkctl)) {
 154                         err = -ENODEV;
 155                         mlx4_err(dev, "Couldn't restore HCA PCI Express Link control register, aborting\n");
 156                         goto out;
 157                 }
 158         }
 159
 160         for (i = 0; i < 16; ++i) {
 161                 if (i * 4 == PCI_COMMAND)
 162                         continue;
 163
 164                 if (pci_write_config_dword(dev->persist->pdev, i * 4,
 165                                            hca_header[i])) {
 166                         err = -ENODEV;
 167                         mlx4_err(dev, "Couldn't restore HCA reg %x, aborting\n",
 168                                  i);
 169                         goto out;
 170                 }
 171         }
 172
 173         if (pci_write_config_dword(dev->persist->pdev, PCI_COMMAND,
 174                                    hca_header[PCI_COMMAND / 4])) {
 175                 err = -ENODEV;
 176                 mlx4_err(dev, "Couldn't restore HCA COMMAND, aborting\n");
 177                 goto out;
 178         }
 179
 180 out:
 181         kfree(hca_header);
 182
 183         return err;
 184 }