aboutsummaryrefslogtreecommitdiff
path: root/drivers/net/mlx4/reset.c
blob: 11e7c1cb99bf30d001ad5127d9d1965f741d6d70 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
/*
 * Copyright (c) 2006, 2007 Cisco Systems, Inc.  All rights reserved.
 * Copyright (c) 2007, 2008 Mellanox Technologies. All rights reserved.
 *
 * This software is available to you under a choice of one of two
 * licenses.  You may choose to be licensed under the terms of the GNU
 * General Public License (GPL) Version 2, available from the file
 * COPYING in the main directory of this source tree, or the
 * OpenIB.org BSD license below:
 *
 *     Redistribution and use in source and binary forms, with or
 *     without modification, are permitted provided that the following
 *     conditions are met:
 *
 *      - Redistributions of source code must retain the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer.
 *
 *      - Redistributions in binary form must reproduce the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer in the documentation and/or other materials
 *        provided with the distribution.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#include <linux/errno.h>
#include <linux/pci.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/jiffies.h>

#include "mlx4.h"

int mlx4_reset(struct mlx4_dev *dev)
{
	void __iomem *reset;
	u32 *hca_header = NULL;
	int pcie_cap;
	u16 devctl;
	u16 linkctl;
	u16 vendor;
	unsigned long end;
	u32 sem;
	int i;
	int err = 0;

#define MLX4_RESET_BASE		0xf0000
#define MLX4_RESET_SIZE		  0x400
#define MLX4_SEM_OFFSET		  0x3fc
#define MLX4_RESET_OFFSET	   0x10
#define MLX4_RESET_VALUE	swab32(1)

#define MLX4_SEM_TIMEOUT_JIFFIES	(10 * HZ)
#define MLX4_RESET_TIMEOUT_JIFFIES	(2 * HZ)

	/*
	 * Reset the chip.  This is somewhat ugly because we have to
	 * save off the PCI header before reset and then restore it
	 * after the chip reboots.  We skip config space offsets 22
	 * and 23 since those have a special meaning.
	 */

	/* Do we need to save off the full 4K PCI Express header?? */
	hca_header = kmalloc(256, GFP_KERNEL);
	if (!hca_header) {
		err = -ENOMEM;
		mlx4_err(dev, "Couldn't allocate memory to save HCA "
			  "PCI header, aborting.\n");
		goto out;
	}

	pcie_cap = pci_pcie_cap(dev->pdev);

	for (i = 0; i < 64; ++i) {
		if (i == 22 || i == 23)
			continue;
		if (pci_read_config_dword(dev->pdev, i * 4, hca_header + i)) {
			err = -ENODEV;
			mlx4_err(dev, "Couldn't save HCA "
				  "PCI header, aborting.\n");
			goto out;
		}
	}

	reset = ioremap(pci_resource_start(dev->pdev, 0) + MLX4_RESET_BASE,
			MLX4_RESET_SIZE);
	if (!reset) {
		err = -ENOMEM;
		mlx4_err(dev, "Couldn't map HCA reset register, aborting.\n");
		goto out;
	}

	/* grab HW semaphore to lock out flash updates */
	end = jiffies + MLX4_SEM_TIMEOUT_JIFFIES;
	do {
		sem = readl(reset + MLX4_SEM_OFFSET);
		if (!sem)
			break;

		msleep(1);
	} while (time_before(jiffies, end));

	if (sem) {
		mlx4_err(dev, "Failed to obtain HW semaphore, aborting\n");
		err = -EAGAIN;
		iounmap(reset);
		goto out;
	}

	/* actually hit reset */
	writel(MLX4_RESET_VALUE, reset + MLX4_RESET_OFFSET);
	iounmap(reset);

	/* Docs say to wait one second before accessing device */
	msleep(1000);

	end = jiffies + MLX4_RESET_TIMEOUT_JIFFIES;
	do {
		if (!pci_read_config_word(dev->pdev, PCI_VENDOR_ID, &vendor) &&
		    vendor != 0xffff)
			break;

		msleep(1);
	} while (time_before(jiffies, end));

	if (vendor == 0xffff) {
		err = -ENODEV;
		mlx4_err(dev, "PCI device did not come back after reset, "
			  "aborting.\n");
		goto out;
	}

	/* Now restore the PCI headers */
	if (pcie_cap) {
		devctl = hca_header[(pcie_cap + PCI_EXP_DEVCTL) / 4];
		if (pci_write_config_word(dev->pdev, pcie_cap + PCI_EXP_DEVCTL,
					   devctl)) {
			err = -ENODEV;
			mlx4_err(dev, "Couldn't restore HCA PCI Express "
				 "Device Control register, aborting.\n");
			goto out;
		}
		linkctl = hca_header[(pcie_cap + PCI_EXP_LNKCTL) / 4];
		if (pci_write_config_word(dev->pdev, pcie_cap + PCI_EXP_LNKCTL,
					   linkctl)) {
			err = -ENODEV;
			mlx4_err(dev, "Couldn't restore HCA PCI Express "
				 "Link control register, aborting.\n");
			goto out;
		}
	}

	for (i = 0; i < 16; ++i) {
		if (i * 4 == PCI_COMMAND)
			continue;

		if (pci_write_config_dword(dev->pdev, i * 4, hca_header[i])) {
			err = -ENODEV;
			mlx4_err(dev, "Couldn't restore HCA reg %x, "
				  "aborting.\n", i);
			goto out;
		}
	}

	if (pci_write_config_dword(dev->pdev, PCI_COMMAND,
				   hca_header[PCI_COMMAND / 4])) {
		err = -ENODEV;
		mlx4_err(dev, "Couldn't restore HCA COMMAND, "
			  "aborting.\n");
		goto out;
	}

out:
	kfree(hca_header);

	return err;
}