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
14 LIST_HEAD(xen_pcibk_quirks);
15 static inline const struct pci_device_id *
match_one_device(const struct pci_device_id * id,const struct pci_dev * dev)16 match_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
xen_pcibk_find_quirk(struct pci_dev * dev)29 static 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");
39 out:
40 return tmp_quirk;
41 }
42
register_quirk(struct xen_pcibk_config_quirk * quirk)43 static inline void register_quirk(struct xen_pcibk_config_quirk *quirk)
44 {
45 list_add_tail(&quirk->quirks_list, &xen_pcibk_quirks);
46 }
47
xen_pcibk_field_is_dup(struct pci_dev * dev,unsigned int reg)48 int 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
xen_pcibk_config_quirks_add_field(struct pci_dev * dev,struct config_field * field)63 int 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
88 out:
89 return err;
90 }
91
xen_pcibk_config_quirks_init(struct pci_dev * dev)92 int 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);
114 out:
115 return ret;
116 }
117
xen_pcibk_config_field_free(struct config_field * field)118 void xen_pcibk_config_field_free(struct config_field *field)
119 {
120 kfree(field);
121 }
122
xen_pcibk_config_quirk_release(struct pci_dev * dev)123 int 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
137 out:
138 return ret;
139 }
140