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
42int 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(size: 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: 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: dev->persist->pdev, where: i * 4,
85 val: 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(addr: reset + MLX4_SEM_OFFSET);
105 if (!sem)
106 break;
107
108 msleep(msecs: 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(addr: reset);
115 goto out;
116 }
117
118 /* actually hit reset */
119 writel(MLX4_RESET_VALUE, addr: reset + MLX4_RESET_OFFSET);
120 iounmap(addr: reset);
121
122 /* Docs say to wait one second before accessing device */
123 msleep(msecs: 1000);
124
125 end = jiffies + MLX4_RESET_TIMEOUT_JIFFIES;
126 do {
127 if (!pci_read_config_word(dev: dev->persist->pdev, PCI_VENDOR_ID,
128 val: &vendor) && vendor != 0xffff)
129 break;
130
131 msleep(msecs: 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: dev->persist->pdev,
144 PCI_EXP_DEVCTL,
145 val: 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: dev->persist->pdev,
152 PCI_EXP_LNKCTL,
153 val: 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: dev->persist->pdev, where: i * 4,
165 val: 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: dev->persist->pdev, PCI_COMMAND,
174 val: hca_header[PCI_COMMAND / 4])) {
175 err = -ENODEV;
176 mlx4_err(dev, "Couldn't restore HCA COMMAND, aborting\n");
177 goto out;
178 }
179
180out:
181 kfree(objp: hca_header);
182
183 return err;
184}
185

source code of linux/drivers/net/ethernet/mellanox/mlx4/reset.c