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
mlx4_reset(struct mlx4_dev * dev)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_find_capability(dev->pdev, PCI_CAP_ID_EXP);
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 /* 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->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 (pci_write_config_word(dev->pdev, pcie_cap + 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 (pci_write_config_word(dev->pdev, pcie_cap + 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