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/init.h>
35 #include <linux/errno.h>
36 #include <linux/pci.h>
37 #include <linux/delay.h>
38 #include <linux/slab.h>
39 #include <linux/jiffies.h>
40
41 #include "mlx4.h"
42
mlx4_reset(struct mlx4_dev * dev)43 int mlx4_reset(struct mlx4_dev *dev)
44 {
45 void __iomem *reset;
46 u32 *hca_header = NULL;
47 int pcie_cap;
48 u16 devctl;
49 u16 linkctl;
50 u16 vendor;
51 unsigned long end;
52 u32 sem;
53 int i;
54 int err = 0;
55
56 #define MLX4_RESET_BASE 0xf0000
57 #define MLX4_RESET_SIZE 0x400
58 #define MLX4_SEM_OFFSET 0x3fc
59 #define MLX4_RESET_OFFSET 0x10
60 #define MLX4_RESET_VALUE swab32(1)
61
62 #define MLX4_SEM_TIMEOUT_JIFFIES (10 * HZ)
63 #define MLX4_RESET_TIMEOUT_JIFFIES (2 * HZ)
64
65 /*
66 * Reset the chip. This is somewhat ugly because we have to
67 * save off the PCI header before reset and then restore it
68 * after the chip reboots. We skip config space offsets 22
69 * and 23 since those have a special meaning.
70 */
71
72 /* Do we need to save off the full 4K PCI Express header?? */
73 hca_header = kmalloc(256, GFP_KERNEL);
74 if (!hca_header) {
75 err = -ENOMEM;
76 mlx4_err(dev, "Couldn't allocate memory to save HCA "
77 "PCI header, aborting.\n");
78 goto out;
79 }
80
81 pcie_cap = pci_find_capability(dev->pdev, PCI_CAP_ID_EXP);
82
83 for (i = 0; i < 64; ++i) {
84 if (i == 22 || i == 23)
85 continue;
86 if (pci_read_config_dword(dev->pdev, i * 4, hca_header + i)) {
87 err = -ENODEV;
88 mlx4_err(dev, "Couldn't save HCA "
89 "PCI header, aborting.\n");
90 goto out;
91 }
92 }
93
94 reset = ioremap(pci_resource_start(dev->pdev, 0) + MLX4_RESET_BASE,
95 MLX4_RESET_SIZE);
96 if (!reset) {
97 err = -ENOMEM;
98 mlx4_err(dev, "Couldn't map HCA reset register, aborting.\n");
99 goto out;
100 }
101
102 /* grab HW semaphore to lock out flash updates */
103 end = jiffies + MLX4_SEM_TIMEOUT_JIFFIES;
104 do {
105 sem = readl(reset + MLX4_SEM_OFFSET);
106 if (!sem)
107 break;
108
109 msleep(1);
110 } while (time_before(jiffies, end));
111
112 if (sem) {
113 mlx4_err(dev, "Failed to obtain HW semaphore, aborting\n");
114 err = -EAGAIN;
115 iounmap(reset);
116 goto out;
117 }
118
119 /* actually hit reset */
120 writel(MLX4_RESET_VALUE, reset + MLX4_RESET_OFFSET);
121 iounmap(reset);
122
123 /* Docs say to wait one second before accessing device */
124 msleep(1000);
125
126 end = jiffies + MLX4_RESET_TIMEOUT_JIFFIES;
127 do {
128 if (!pci_read_config_word(dev->pdev, PCI_VENDOR_ID, &vendor) &&
129 vendor != 0xffff)
130 break;
131
132 msleep(1);
133 } while (time_before(jiffies, end));
134
135 if (vendor == 0xffff) {
136 err = -ENODEV;
137 mlx4_err(dev, "PCI device did not come back after reset, "
138 "aborting.\n");
139 goto out;
140 }
141
142 /* Now restore the PCI headers */
143 if (pcie_cap) {
144 devctl = hca_header[(pcie_cap + PCI_EXP_DEVCTL) / 4];
145 if (pci_write_config_word(dev->pdev, pcie_cap + PCI_EXP_DEVCTL,
146 devctl)) {
147 err = -ENODEV;
148 mlx4_err(dev, "Couldn't restore HCA PCI Express "
149 "Device Control register, aborting.\n");
150 goto out;
151 }
152 linkctl = hca_header[(pcie_cap + PCI_EXP_LNKCTL) / 4];
153 if (pci_write_config_word(dev->pdev, pcie_cap + PCI_EXP_LNKCTL,
154 linkctl)) {
155 err = -ENODEV;
156 mlx4_err(dev, "Couldn't restore HCA PCI Express "
157 "Link control register, aborting.\n");
158 goto out;
159 }
160 }
161
162 for (i = 0; i < 16; ++i) {
163 if (i * 4 == PCI_COMMAND)
164 continue;
165
166 if (pci_write_config_dword(dev->pdev, i * 4, hca_header[i])) {
167 err = -ENODEV;
168 mlx4_err(dev, "Couldn't restore HCA reg %x, "
169 "aborting.\n", i);
170 goto out;
171 }
172 }
173
174 if (pci_write_config_dword(dev->pdev, PCI_COMMAND,
175 hca_header[PCI_COMMAND / 4])) {
176 err = -ENODEV;
177 mlx4_err(dev, "Couldn't restore HCA COMMAND, "
178 "aborting.\n");
179 goto out;
180 }
181
182 out:
183 kfree(hca_header);
184
185 return err;
186 }
187