conf_space_quirks.c revision 402c5e15b44070461dcc2f41536c16d0cfbca9c3 
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);
15static inline const struct pci_device_id *
16match_one_device(const struct pci_device_id *id, const struct pci_dev *dev)
17{
18	if ((id->vendor == PCI_ANY_ID || id->vendor == dev->vendor) &&
19	    (id->device == PCI_ANY_ID || id->device == dev->device) &&
20	    (id->subvendor == PCI_ANY_ID ||
21				id->subvendor == dev->subsystem_vendor) &&
22	    (id->subdevice == PCI_ANY_ID ||
23				id->subdevice == dev->subsystem_device) &&
24	    !((id->class ^ dev->class) & id->class_mask))
25		return id;
26	return NULL;
27}
28
29static struct xen_pcibk_config_quirk *xen_pcibk_find_quirk(struct pci_dev *dev)
30{
31	struct xen_pcibk_config_quirk *tmp_quirk;
32
33	list_for_each_entry(tmp_quirk, &xen_pcibk_quirks, quirks_list)
34		if (match_one_device(&tmp_quirk->devid, dev) != NULL)
35			goto out;
36	tmp_quirk = NULL;
37	printk(KERN_DEBUG DRV_NAME
38	       ": quirk didn't match any device known\n");
39out:
40	return tmp_quirk;
41}
42
43static inline void register_quirk(struct xen_pcibk_config_quirk *quirk)
44{
45	list_add_tail(&quirk->quirks_list, &xen_pcibk_quirks);
46}
47
48int xen_pcibk_field_is_dup(struct pci_dev *dev, unsigned int reg)
49{
50	int ret = 0;
51	struct xen_pcibk_dev_data *dev_data = pci_get_drvdata(dev);
52	struct config_field_entry *cfg_entry;
53
54	list_for_each_entry(cfg_entry, &dev_data->config_fields, list) {
55		if (OFFSET(cfg_entry) == reg) {
56			ret = 1;
57			break;
58		}
59	}
60	return ret;
61}
62
63int xen_pcibk_config_quirks_add_field(struct pci_dev *dev, struct config_field
64				    *field)
65{
66	int err = 0;
67
68	switch (field->size) {
69	case 1:
70		field->u.b.read = xen_pcibk_read_config_byte;
71		field->u.b.write = xen_pcibk_write_config_byte;
72		break;
73	case 2:
74		field->u.w.read = xen_pcibk_read_config_word;
75		field->u.w.write = xen_pcibk_write_config_word;
76		break;
77	case 4:
78		field->u.dw.read = xen_pcibk_read_config_dword;
79		field->u.dw.write = xen_pcibk_write_config_dword;
80		break;
81	default:
82		err = -EINVAL;
83		goto out;
84	}
85
86	xen_pcibk_config_add_field(dev, field);
87
88out:
89	return err;
90}
91
92int xen_pcibk_config_quirks_init(struct pci_dev *dev)
93{
94	struct xen_pcibk_config_quirk *quirk;
95	int ret = 0;
96
97	quirk = kzalloc(sizeof(*quirk), GFP_ATOMIC);
98	if (!quirk) {
99		ret = -ENOMEM;
100		goto out;
101	}
102
103	quirk->devid.vendor = dev->vendor;
104	quirk->devid.device = dev->device;
105	quirk->devid.subvendor = dev->subsystem_vendor;
106	quirk->devid.subdevice = dev->subsystem_device;
107	quirk->devid.class = 0;
108	quirk->devid.class_mask = 0;
109	quirk->devid.driver_data = 0UL;
110
111	quirk->pdev = dev;
112
113	register_quirk(quirk);
114out:
115	return ret;
116}
117
118void xen_pcibk_config_field_free(struct config_field *field)
119{
120	kfree(field);
121}
122
123int xen_pcibk_config_quirk_release(struct pci_dev *dev)
124{
125	struct xen_pcibk_config_quirk *quirk;
126	int ret = 0;
127
128	quirk = xen_pcibk_find_quirk(dev);
129	if (!quirk) {
130		ret = -ENXIO;
131		goto out;
132	}
133
134	list_del(&quirk->quirks_list);
135	kfree(quirk);
136
137out:
138	return ret;
139}
140