conf_space_quirks.c revision a92336a1176b2119eaa990a1e8bf3109665fdbc6 
1/*
2 * PCI Backend - Handle special overlays for broken devices.
3 *
4 * Author: Ryan Wilson <hap9@epoch.ncsc.mil>
5 * Author: Chris Bookholt <hap10@epoch.ncsc.mil>
6 */
7
8#include <linux/kernel.h>
9#include <linux/pci.h>
10#include "pciback.h"
11#include "conf_space.h"
12#include "conf_space_quirks.h"
13
14LIST_HEAD(xen_pcibk_quirks);
15#define	DRV_NAME	"xen-pciback"
16static inline const struct pci_device_id *
17match_one_device(const struct pci_device_id *id, const struct pci_dev *dev)
18{
19	if ((id->vendor == PCI_ANY_ID || id->vendor == dev->vendor) &&
20	    (id->device == PCI_ANY_ID || id->device == dev->device) &&
21	    (id->subvendor == PCI_ANY_ID ||
22				id->subvendor == dev->subsystem_vendor) &&
23	    (id->subdevice == PCI_ANY_ID ||
24				id->subdevice == dev->subsystem_device) &&
25	    !((id->class ^ dev->class) & id->class_mask))
26		return id;
27	return NULL;
28}
29
30static struct xen_pcibk_config_quirk *xen_pcibk_find_quirk(struct pci_dev *dev)
31{
32	struct xen_pcibk_config_quirk *tmp_quirk;
33
34	list_for_each_entry(tmp_quirk, &xen_pcibk_quirks, quirks_list)
35		if (match_one_device(&tmp_quirk->devid, dev) != NULL)
36			goto out;
37	tmp_quirk = NULL;
38	printk(KERN_DEBUG DRV_NAME
39	       ":quirk didn't match any device xen_pciback knows about\n");
40out:
41	return tmp_quirk;
42}
43
44static inline void register_quirk(struct xen_pcibk_config_quirk *quirk)
45{
46	list_add_tail(&quirk->quirks_list, &xen_pcibk_quirks);
47}
48
49int xen_pcibk_field_is_dup(struct pci_dev *dev, unsigned int reg)
50{
51	int ret = 0;
52	struct xen_pcibk_dev_data *dev_data = pci_get_drvdata(dev);
53	struct config_field_entry *cfg_entry;
54
55	list_for_each_entry(cfg_entry, &dev_data->config_fields, list) {
56		if (OFFSET(cfg_entry) == reg) {
57			ret = 1;
58			break;
59		}
60	}
61	return ret;
62}
63
64int xen_pcibk_config_quirks_add_field(struct pci_dev *dev, struct config_field
65				    *field)
66{
67	int err = 0;
68
69	switch (field->size) {
70	case 1:
71		field->u.b.read = xen_pcibk_read_config_byte;
72		field->u.b.write = xen_pcibk_write_config_byte;
73		break;
74	case 2:
75		field->u.w.read = xen_pcibk_read_config_word;
76		field->u.w.write = xen_pcibk_write_config_word;
77		break;
78	case 4:
79		field->u.dw.read = xen_pcibk_read_config_dword;
80		field->u.dw.write = xen_pcibk_write_config_dword;
81		break;
82	default:
83		err = -EINVAL;
84		goto out;
85	}
86
87	xen_pcibk_config_add_field(dev, field);
88
89out:
90	return err;
91}
92
93int xen_pcibk_config_quirks_init(struct pci_dev *dev)
94{
95	struct xen_pcibk_config_quirk *quirk;
96	int ret = 0;
97
98	quirk = kzalloc(sizeof(*quirk), GFP_ATOMIC);
99	if (!quirk) {
100		ret = -ENOMEM;
101		goto out;
102	}
103
104	quirk->devid.vendor = dev->vendor;
105	quirk->devid.device = dev->device;
106	quirk->devid.subvendor = dev->subsystem_vendor;
107	quirk->devid.subdevice = dev->subsystem_device;
108	quirk->devid.class = 0;
109	quirk->devid.class_mask = 0;
110	quirk->devid.driver_data = 0UL;
111
112	quirk->pdev = dev;
113
114	register_quirk(quirk);
115out:
116	return ret;
117}
118
119void xen_pcibk_config_field_free(struct config_field *field)
120{
121	kfree(field);
122}
123
124int xen_pcibk_config_quirk_release(struct pci_dev *dev)
125{
126	struct xen_pcibk_config_quirk *quirk;
127	int ret = 0;
128
129	quirk = xen_pcibk_find_quirk(dev);
130	if (!quirk) {
131		ret = -ENXIO;
132		goto out;
133	}
134
135	list_del(&quirk->quirks_list);
136	kfree(quirk);
137
138out:
139	return ret;
140}
141