xref: /openbmc/linux/drivers/xen/platform-pci.c (revision 2d96b44f)
1 /******************************************************************************
2  * platform-pci.c
3  *
4  * Xen platform PCI device driver
5  *
6  * Authors: ssmith@xensource.com and stefano.stabellini@eu.citrix.com
7  *
8  * Copyright (c) 2005, Intel Corporation.
9  * Copyright (c) 2007, XenSource Inc.
10  * Copyright (c) 2010, Citrix
11  *
12  * This program is free software; you can redistribute it and/or modify it
13  * under the terms and conditions of the GNU General Public License,
14  * version 2, as published by the Free Software Foundation.
15  *
16  * This program is distributed in the hope it will be useful, but WITHOUT
17  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
18  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
19  * more details.
20  *
21  * You should have received a copy of the GNU General Public License along with
22  * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
23  * Place - Suite 330, Boston, MA 02111-1307 USA.
24  *
25  */
26 
27 
28 #include <linux/interrupt.h>
29 #include <linux/io.h>
30 #include <linux/init.h>
31 #include <linux/pci.h>
32 
33 #include <xen/platform_pci.h>
34 #include <xen/grant_table.h>
35 #include <xen/xenbus.h>
36 #include <xen/events.h>
37 #include <xen/hvm.h>
38 #include <xen/xen-ops.h>
39 
40 #define DRV_NAME    "xen-platform-pci"
41 
42 static unsigned long platform_mmio;
43 static unsigned long platform_mmio_alloc;
44 static unsigned long platform_mmiolen;
45 
46 static unsigned long alloc_xen_mmio(unsigned long len)
47 {
48 	unsigned long addr;
49 
50 	addr = platform_mmio + platform_mmio_alloc;
51 	platform_mmio_alloc += len;
52 	BUG_ON(platform_mmio_alloc > platform_mmiolen);
53 
54 	return addr;
55 }
56 
57 static int platform_pci_probe(struct pci_dev *pdev,
58 			      const struct pci_device_id *ent)
59 {
60 	int i, ret;
61 	long ioaddr;
62 	long mmio_addr, mmio_len;
63 	unsigned int max_nr_gframes;
64 	unsigned long grant_frames;
65 
66 	if (!xen_domain())
67 		return -ENODEV;
68 
69 	i = pci_enable_device(pdev);
70 	if (i)
71 		return i;
72 
73 	ioaddr = pci_resource_start(pdev, 0);
74 
75 	mmio_addr = pci_resource_start(pdev, 1);
76 	mmio_len = pci_resource_len(pdev, 1);
77 
78 	if (mmio_addr == 0 || ioaddr == 0) {
79 		dev_err(&pdev->dev, "no resources found\n");
80 		ret = -ENOENT;
81 		goto pci_out;
82 	}
83 
84 	ret = pci_request_region(pdev, 1, DRV_NAME);
85 	if (ret < 0)
86 		goto pci_out;
87 
88 	ret = pci_request_region(pdev, 0, DRV_NAME);
89 	if (ret < 0)
90 		goto mem_out;
91 
92 	platform_mmio = mmio_addr;
93 	platform_mmiolen = mmio_len;
94 
95 	max_nr_gframes = gnttab_max_grant_frames();
96 	grant_frames = alloc_xen_mmio(PAGE_SIZE * max_nr_gframes);
97 	ret = gnttab_setup_auto_xlat_frames(grant_frames);
98 	if (ret)
99 		goto out;
100 	ret = gnttab_init();
101 	if (ret)
102 		goto grant_out;
103 	xenbus_probe(NULL);
104 	return 0;
105 grant_out:
106 	gnttab_free_auto_xlat_frames();
107 out:
108 	pci_release_region(pdev, 0);
109 mem_out:
110 	pci_release_region(pdev, 1);
111 pci_out:
112 	pci_disable_device(pdev);
113 	return ret;
114 }
115 
116 static struct pci_device_id platform_pci_tbl[] = {
117 	{PCI_VENDOR_ID_XEN, PCI_DEVICE_ID_XEN_PLATFORM,
118 		PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0},
119 	{0,}
120 };
121 
122 static struct pci_driver platform_driver = {
123 	.name =           DRV_NAME,
124 	.probe =          platform_pci_probe,
125 	.id_table =       platform_pci_tbl,
126 };
127 
128 static int __init platform_pci_init(void)
129 {
130 	return pci_register_driver(&platform_driver);
131 }
132 device_initcall(platform_pci_init);
133