1 /* 2 * Copyright (c) 2006, 2007 Cisco Systems, Inc. All rights reserved. 3 * Copyright (c) 2007, 2008, 2014 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 " 76 "PCI header, aborting.\n"); 77 goto out; 78 } 79 80 pcie_cap = pci_pcie_cap(dev->pdev); 81 82 for (i = 0; i < 64; ++i) { 83 if (i == 22 || i == 23) 84 continue; 85 if (pci_read_config_dword(dev->pdev, i * 4, hca_header + i)) { 86 err = -ENODEV; 87 mlx4_err(dev, "Couldn't save HCA " 88 "PCI header, aborting.\n"); 89 goto out; 90 } 91 } 92 93 reset = ioremap(pci_resource_start(dev->pdev, 0) + 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 /* wait half a second before accessing device */ 123 msleep(500); 124 125 end = jiffies + MLX4_RESET_TIMEOUT_JIFFIES; 126 do { 127 if (!pci_read_config_word(dev->pdev, PCI_VENDOR_ID, &vendor) && 128 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, " 137 "aborting.\n"); 138 goto out; 139 } 140 141 /* Now restore the PCI headers */ 142 if (pcie_cap) { 143 devctl = hca_header[(pcie_cap + PCI_EXP_DEVCTL) / 4]; 144 if (pcie_capability_write_word(dev->pdev, PCI_EXP_DEVCTL, 145 devctl)) { 146 err = -ENODEV; 147 mlx4_err(dev, "Couldn't restore HCA PCI Express " 148 "Device Control register, aborting.\n"); 149 goto out; 150 } 151 linkctl = hca_header[(pcie_cap + PCI_EXP_LNKCTL) / 4]; 152 if (pcie_capability_write_word(dev->pdev, PCI_EXP_LNKCTL, 153 linkctl)) { 154 err = -ENODEV; 155 mlx4_err(dev, "Couldn't restore HCA PCI Express " 156 "Link control register, aborting.\n"); 157 goto out; 158 } 159 } 160 161 for (i = 0; i < 16; ++i) { 162 if (i * 4 == PCI_COMMAND) 163 continue; 164 165 if (pci_write_config_dword(dev->pdev, i * 4, hca_header[i])) { 166 err = -ENODEV; 167 mlx4_err(dev, "Couldn't restore HCA reg %x, " 168 "aborting.\n", i); 169 goto out; 170 } 171 } 172 173 if (pci_write_config_dword(dev->pdev, PCI_COMMAND, 174 hca_header[PCI_COMMAND / 4])) { 175 err = -ENODEV; 176 mlx4_err(dev, "Couldn't restore HCA COMMAND, " 177 "aborting.\n"); 178 goto out; 179 } 180 181 out: 182 kfree(hca_header); 183 184 return err; 185 } 186