xref: /linux/drivers/xen/xen-pciback/conf_space.h (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 /*
2  * PCI Backend - Common data structures for overriding the configuration space
3  *
4  * Author: Ryan Wilson <hap9@epoch.ncsc.mil>
5  */
6 
7 #ifndef __XEN_PCIBACK_CONF_SPACE_H__
8 #define __XEN_PCIBACK_CONF_SPACE_H__
9 
10 #include <linux/list.h>
11 #include <linux/err.h>
12 
13 /* conf_field_init can return an errno in a ptr with ERR_PTR() */
14 typedef void *(*conf_field_init) (struct pci_dev *dev, int offset);
15 typedef void (*conf_field_reset) (struct pci_dev *dev, int offset, void *data);
16 typedef void (*conf_field_free) (struct pci_dev *dev, int offset, void *data);
17 
18 typedef int (*conf_dword_write) (struct pci_dev *dev, int offset, u32 value,
19 				 void *data);
20 typedef int (*conf_word_write) (struct pci_dev *dev, int offset, u16 value,
21 				void *data);
22 typedef int (*conf_byte_write) (struct pci_dev *dev, int offset, u8 value,
23 				void *data);
24 typedef int (*conf_dword_read) (struct pci_dev *dev, int offset, u32 *value,
25 				void *data);
26 typedef int (*conf_word_read) (struct pci_dev *dev, int offset, u16 *value,
27 			       void *data);
28 typedef int (*conf_byte_read) (struct pci_dev *dev, int offset, u8 *value,
29 			       void *data);
30 
31 /* These are the fields within the configuration space which we
32  * are interested in intercepting reads/writes to and changing their
33  * values.
34  */
35 struct config_field {
36 	unsigned int offset;
37 	unsigned int size;
38 	unsigned int mask;
39 	conf_field_init init;
40 	conf_field_reset reset;
41 	conf_field_free release;
42 	void (*clean) (struct config_field *field);
43 	union {
44 		struct {
45 			conf_dword_write write;
46 			conf_dword_read read;
47 		} dw;
48 		struct {
49 			conf_word_write write;
50 			conf_word_read read;
51 		} w;
52 		struct {
53 			conf_byte_write write;
54 			conf_byte_read read;
55 		} b;
56 	} u;
57 	struct list_head list;
58 };
59 
60 struct config_field_entry {
61 	struct list_head list;
62 	const struct config_field *field;
63 	unsigned int base_offset;
64 	void *data;
65 };
66 
67 extern bool xen_pcibk_permissive;
68 
69 #define OFFSET(cfg_entry) ((cfg_entry)->base_offset+(cfg_entry)->field->offset)
70 
71 /* Add fields to a device - the add_fields macro expects to get a pointer to
72  * the first entry in an array (of which the ending is marked by size==0)
73  */
74 int xen_pcibk_config_add_field_offset(struct pci_dev *dev,
75 				    const struct config_field *field,
76 				    unsigned int offset);
77 
78 static inline int xen_pcibk_config_add_field(struct pci_dev *dev,
79 					   const struct config_field *field)
80 {
81 	return xen_pcibk_config_add_field_offset(dev, field, 0);
82 }
83 
84 static inline int xen_pcibk_config_add_fields(struct pci_dev *dev,
85 					    const struct config_field *field)
86 {
87 	int i, err = 0;
88 	for (i = 0; field[i].size != 0; i++) {
89 		err = xen_pcibk_config_add_field(dev, &field[i]);
90 		if (err)
91 			break;
92 	}
93 	return err;
94 }
95 
96 static inline int xen_pcibk_config_add_fields_offset(struct pci_dev *dev,
97 					const struct config_field *field,
98 					unsigned int offset)
99 {
100 	int i, err = 0;
101 	for (i = 0; field[i].size != 0; i++) {
102 		err = xen_pcibk_config_add_field_offset(dev, &field[i], offset);
103 		if (err)
104 			break;
105 	}
106 	return err;
107 }
108 
109 /* Read/Write the real configuration space */
110 int xen_pcibk_read_config_byte(struct pci_dev *dev, int offset, u8 *value,
111 			       void *data);
112 int xen_pcibk_read_config_word(struct pci_dev *dev, int offset, u16 *value,
113 			       void *data);
114 int xen_pcibk_read_config_dword(struct pci_dev *dev, int offset, u32 *value,
115 				void *data);
116 int xen_pcibk_write_config_byte(struct pci_dev *dev, int offset, u8 value,
117 				 void *data);
118 int xen_pcibk_write_config_word(struct pci_dev *dev, int offset, u16 value,
119 				void *data);
120 int xen_pcibk_write_config_dword(struct pci_dev *dev, int offset, u32 value,
121 				 void *data);
122 
123 int xen_pcibk_config_capability_init(void);
124 
125 int xen_pcibk_config_header_add_fields(struct pci_dev *dev);
126 int xen_pcibk_config_capability_add_fields(struct pci_dev *dev);
127 
128 #endif				/* __XEN_PCIBACK_CONF_SPACE_H__ */
129