summaryrefslogtreecommitdiffstats
path: root/drivers/dma/ioat.c
blob: a45872f32d505f138efffca1a27ea8256874db2d (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
186
187
188
189
190
191
192
193
194
195
196
197
198
199
/*
 * Intel I/OAT DMA Linux driver
 * Copyright(c) 2007 Intel Corporation.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * The full GNU General Public License is included in this distribution in
 * the file called "COPYING".
 *
 */

/*
 * This driver supports an Intel I/OAT DMA engine, which does asynchronous
 * copy operations.
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/interrupt.h>
#include <linux/dca.h>
#include "ioatdma.h"
#include "ioatdma_registers.h"
#include "ioatdma_hw.h"

MODULE_VERSION("1.24");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Intel Corporation");

static struct pci_device_id ioat_pci_tbl[] = {
	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT) },
	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT_CNB)  },
	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT_SCNB) },
	{ PCI_DEVICE(PCI_VENDOR_ID_UNISYS, PCI_DEVICE_ID_UNISYS_DMA_DIRECTOR) },
	{ 0, }
};

struct ioat_device {
	struct pci_dev		*pdev;
	void __iomem		*iobase;
	struct ioatdma_device	*dma;
	struct dca_provider	*dca;
};

static int __devinit ioat_probe(struct pci_dev *pdev,
				const struct pci_device_id *id);
static void __devexit ioat_remove(struct pci_dev *pdev);

static int ioat_dca_enabled = 1;
module_param(ioat_dca_enabled, int, 0644);
MODULE_PARM_DESC(ioat_dca_enabled, "control support of dca service (default: 1)");

static int ioat_setup_functionality(struct pci_dev *pdev, void __iomem *iobase)
{
	struct ioat_device *device = pci_get_drvdata(pdev);
	u8 version;
	int err = 0;

	version = readb(iobase + IOAT_VER_OFFSET);
	switch (version) {
	case IOAT_VER_1_2:
		device->dma = ioat_dma_probe(pdev, iobase);
		if (device->dma && ioat_dca_enabled)
			device->dca = ioat_dca_init(pdev, iobase);
		break;
	default:
		err = -ENODEV;
		break;
	}
	return err;
}

static void ioat_shutdown_functionality(struct pci_dev *pdev)
{
	struct ioat_device *device = pci_get_drvdata(pdev);

	if (device->dca) {
		unregister_dca_provider(device->dca);
		free_dca_provider(device->dca);
		device->dca = NULL;
	}

	if (device->dma) {
		ioat_dma_remove(device->dma);
		device->dma = NULL;
	}
}

static struct pci_driver ioat_pci_driver = {
	.name		= "ioatdma",
	.id_table	= ioat_pci_tbl,
	.probe		= ioat_probe,
	.shutdown	= ioat_shutdown_functionality,
	.remove		= __devexit_p(ioat_remove),
};

static int __devinit ioat_probe(struct pci_dev *pdev,
				const struct pci_device_id *id)
{
	void __iomem *iobase;
	struct ioat_device *device;
	unsigned long mmio_start, mmio_len;
	int err;

	err = pci_enable_device(pdev);
	if (err)
		goto err_enable_device;

	err = pci_request_regions(pdev, ioat_pci_driver.name);
	if (err)
		goto err_request_regions;

	err = pci_set_dma_mask(pdev, DMA_64BIT_MASK);
	if (err)
		err = pci_set_dma_mask(pdev, DMA_32BIT_MASK);
	if (err)
		goto err_set_dma_mask;

	err = pci_set_consistent_dma_mask(pdev, DMA_64BIT_MASK);
	if (err)
		err = pci_set_consistent_dma_mask(pdev, DMA_32BIT_MASK);
	if (err)
		goto err_set_dma_mask;

	mmio_start = pci_resource_start(pdev, 0);
	mmio_len = pci_resource_len(pdev, 0);
	iobase = ioremap(mmio_start, mmio_len);
	if (!iobase) {
		err = -ENOMEM;
		goto err_ioremap;
	}

	device = kzalloc(sizeof(*device), GFP_KERNEL);
	if (!device) {
		err = -ENOMEM;
		goto err_kzalloc;
	}
	device->pdev = pdev;
	pci_set_drvdata(pdev, device);
	device->iobase = iobase;

	pci_set_master(pdev);

	err = ioat_setup_functionality(pdev, iobase);
	if (err)
		goto err_version;

	return 0;

err_version:
	kfree(device);
err_kzalloc:
	iounmap(iobase);
err_ioremap:
err_set_dma_mask:
	pci_release_regions(pdev);
	pci_disable_device(pdev);
err_request_regions:
err_enable_device:
	return err;
}

/*
 * It is unsafe to remove this module: if removed while a requested
 * dma is outstanding, esp. from tcp, it is possible to hang while
 * waiting for something that will never finish.  However, if you're
 * feeling lucky, this usually works just fine.
 */
static void __devexit ioat_remove(struct pci_dev *pdev)
{
	struct ioat_device *device = pci_get_drvdata(pdev);

	ioat_shutdown_functionality(pdev);

	kfree(device);
}

static int __init ioat_init_module(void)
{
	return pci_register_driver(&ioat_pci_driver);
}
module_init(ioat_init_module);

static void __exit ioat_exit_module(void)
{
	pci_unregister_driver(&ioat_pci_driver);
}
module_exit(ioat_exit_module);
OpenPOWER on IntegriCloud