xref: /openbmc/linux/arch/powerpc/include/asm/nvram.h (revision d9fd5a71)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * NVRAM definitions and access functions.
4  */
5 #ifndef _ASM_POWERPC_NVRAM_H
6 #define _ASM_POWERPC_NVRAM_H
7 
8 #include <linux/types.h>
9 #include <linux/errno.h>
10 #include <linux/list.h>
11 #include <uapi/asm/nvram.h>
12 
13 /*
14  * Set oops header version to distinguish between old and new format header.
15  * lnx,oops-log partition max size is 4000, header version > 4000 will
16  * help in identifying new header.
17  */
18 #define OOPS_HDR_VERSION 5000
19 
20 struct err_log_info {
21 	__be32 error_type;
22 	__be32 seq_num;
23 };
24 
25 struct nvram_os_partition {
26 	const char *name;
27 	int req_size;	/* desired size, in bytes */
28 	int min_size;	/* minimum acceptable size (0 means req_size) */
29 	long size;	/* size of data portion (excluding err_log_info) */
30 	long index;	/* offset of data portion of partition */
31 	bool os_partition; /* partition initialized by OS, not FW */
32 };
33 
34 struct oops_log_info {
35 	__be16 version;
36 	__be16 report_length;
37 	__be64 timestamp;
38 } __attribute__((packed));
39 
40 extern struct nvram_os_partition oops_log_partition;
41 
42 #ifdef CONFIG_PPC_PSERIES
43 extern struct nvram_os_partition rtas_log_partition;
44 
45 extern int nvram_write_error_log(char * buff, int length,
46 					 unsigned int err_type, unsigned int err_seq);
47 extern int nvram_read_error_log(char * buff, int length,
48 					 unsigned int * err_type, unsigned int *err_seq);
49 extern int nvram_clear_error_log(void);
50 extern int pSeries_nvram_init(void);
51 #endif /* CONFIG_PPC_PSERIES */
52 
53 #ifdef CONFIG_MMIO_NVRAM
54 extern int mmio_nvram_init(void);
55 #else
56 static inline int mmio_nvram_init(void)
57 {
58 	return -ENODEV;
59 }
60 #endif
61 
62 extern int __init nvram_scan_partitions(void);
63 extern loff_t nvram_create_partition(const char *name, int sig,
64 				     int req_size, int min_size);
65 extern int nvram_remove_partition(const char *name, int sig,
66 					const char *exceptions[]);
67 extern int nvram_get_partition_size(loff_t data_index);
68 extern loff_t nvram_find_partition(const char *name, int sig, int *out_size);
69 
70 /* Return partition offset in nvram */
71 extern int	pmac_get_partition(int partition);
72 
73 /* Direct access to XPRAM on PowerMacs */
74 extern u8	pmac_xpram_read(int xpaddr);
75 extern void	pmac_xpram_write(int xpaddr, u8 data);
76 
77 /* Initialize NVRAM OS partition */
78 extern int __init nvram_init_os_partition(struct nvram_os_partition *part);
79 
80 /* Initialize NVRAM oops partition */
81 extern void __init nvram_init_oops_partition(int rtas_partition_exists);
82 
83 /* Read a NVRAM partition */
84 extern int nvram_read_partition(struct nvram_os_partition *part, char *buff,
85 				int length, unsigned int *err_type,
86 				unsigned int *error_log_cnt);
87 
88 /* Write to NVRAM OS partition */
89 extern int nvram_write_os_partition(struct nvram_os_partition *part,
90 				    char *buff, int length,
91 				    unsigned int err_type,
92 				    unsigned int error_log_cnt);
93 
94 #endif /* _ASM_POWERPC_NVRAM_H */
95