1 /* SPDX-License-Identifier: GPL-2.0 */ <<
2 #ifndef _LINUX_NVRAM_H 1 #ifndef _LINUX_NVRAM_H
3 #define _LINUX_NVRAM_H 2 #define _LINUX_NVRAM_H
4 3
5 #include <linux/errno.h> !! 4 #include <linux/ioctl.h>
6 #include <uapi/linux/nvram.h> <<
7 5
8 #ifdef CONFIG_PPC !! 6 /* /dev/nvram ioctls */
9 #include <asm/machdep.h> !! 7 #define NVRAM_INIT _IO('p', 0x40) /* initialize NVRAM and set checksum */
>> 8 #define NVRAM_SETCKS _IO('p', 0x41) /* recalculate checksum */
>> 9
>> 10 /* for all current systems, this is where NVRAM starts */
>> 11 #define NVRAM_FIRST_BYTE 14
>> 12 /* all these functions expect an NVRAM offset, not an absolute */
>> 13 #define NVRAM_OFFSET(x) ((x)-NVRAM_FIRST_BYTE)
>> 14
>> 15 #ifdef __KERNEL__
>> 16 /* __foo is foo without grabbing the rtc_lock - get it yourself */
>> 17 extern unsigned char __nvram_read_byte(int i);
>> 18 extern unsigned char nvram_read_byte(int i);
>> 19 extern void __nvram_write_byte(unsigned char c, int i);
>> 20 extern void nvram_write_byte(unsigned char c, int i);
>> 21 extern int __nvram_check_checksum(void);
>> 22 extern int nvram_check_checksum(void);
>> 23 extern void __nvram_set_checksum(void);
>> 24 extern void nvram_set_checksum(void);
10 #endif 25 #endif
11 <<
12 /** <<
13 * struct nvram_ops - NVRAM functionality made <<
14 * @read: validate checksum (if any) then load <<
15 * @write: store a range of bytes to NVRAM the <<
16 * @read_byte: load a single byte from NVRAM <<
17 * @write_byte: store a single byte to NVRAM <<
18 * @get_size: return the fixed number of bytes <<
19 * <<
20 * Architectures which provide an nvram ops st <<
21 * of these methods. If the NVRAM hardware can <<
22 * at a time then it may be sufficient to prov <<
23 * If the NVRAM has a checksum (and it is to b <<
24 * .write methods can be used to implement tha <<
25 * <<
26 * Portable drivers may use the wrapper functi <<
27 * The nvram_read() and nvram_write() function <<
28 * methods when available and fall back on the <<
29 * methods otherwise. <<
30 */ <<
31 <<
32 struct nvram_ops { <<
33 ssize_t (*get_size)(void); <<
34 unsigned char (*read_byte)(int); <<
35 void (*write_byte)(unsigned <<
36 ssize_t (*read)(char *, size_t <<
37 ssize_t (*write)(char *, size_ <<
38 #if defined(CONFIG_X86) || defined(CONFIG_M68K <<
39 long (*initialize)(void); <<
40 long (*set_checksum)(void); <<
41 #endif <<
42 }; <<
43 <<
44 extern const struct nvram_ops arch_nvram_ops; <<
45 <<
46 static inline ssize_t nvram_get_size(void) <<
47 { <<
48 #ifdef CONFIG_PPC <<
49 if (ppc_md.nvram_size) <<
50 return ppc_md.nvram_size(); <<
51 #else <<
52 if (arch_nvram_ops.get_size) <<
53 return arch_nvram_ops.get_size <<
54 #endif <<
55 return -ENODEV; <<
56 } <<
57 <<
58 static inline unsigned char nvram_read_byte(in <<
59 { <<
60 #ifdef CONFIG_PPC <<
61 if (ppc_md.nvram_read_val) <<
62 return ppc_md.nvram_read_val(a <<
63 #else <<
64 if (arch_nvram_ops.read_byte) <<
65 return arch_nvram_ops.read_byt <<
66 #endif <<
67 return 0xFF; <<
68 } <<
69 <<
70 static inline void nvram_write_byte(unsigned c <<
71 { <<
72 #ifdef CONFIG_PPC <<
73 if (ppc_md.nvram_write_val) <<
74 ppc_md.nvram_write_val(addr, v <<
75 #else <<
76 if (arch_nvram_ops.write_byte) <<
77 arch_nvram_ops.write_byte(val, <<
78 #endif <<
79 } <<
80 <<
81 static inline ssize_t nvram_read_bytes(char *b <<
82 { <<
83 ssize_t nvram_size = nvram_get_size(); <<
84 loff_t i; <<
85 char *p = buf; <<
86 <<
87 if (nvram_size < 0) <<
88 return nvram_size; <<
89 for (i = *ppos; count > 0 && i < nvram <<
90 *p = nvram_read_byte(i); <<
91 *ppos = i; <<
92 return p - buf; <<
93 } <<
94 <<
95 static inline ssize_t nvram_write_bytes(char * <<
96 { <<
97 ssize_t nvram_size = nvram_get_size(); <<
98 loff_t i; <<
99 char *p = buf; <<
100 <<
101 if (nvram_size < 0) <<
102 return nvram_size; <<
103 for (i = *ppos; count > 0 && i < nvram <<
104 nvram_write_byte(*p, i); <<
105 *ppos = i; <<
106 return p - buf; <<
107 } <<
108 <<
109 static inline ssize_t nvram_read(char *buf, si <<
110 { <<
111 #ifdef CONFIG_PPC <<
112 if (ppc_md.nvram_read) <<
113 return ppc_md.nvram_read(buf, <<
114 #else <<
115 if (arch_nvram_ops.read) <<
116 return arch_nvram_ops.read(buf <<
117 #endif <<
118 return nvram_read_bytes(buf, count, pp <<
119 } <<
120 <<
121 static inline ssize_t nvram_write(char *buf, s <<
122 { <<
123 #ifdef CONFIG_PPC <<
124 if (ppc_md.nvram_write) <<
125 return ppc_md.nvram_write(buf, <<
126 #else <<
127 if (arch_nvram_ops.write) <<
128 return arch_nvram_ops.write(bu <<
129 #endif <<
130 return nvram_write_bytes(buf, count, p <<
131 } <<
132 26
133 #endif /* _LINUX_NVRAM_H */ 27 #endif /* _LINUX_NVRAM_H */
134 28
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