xref: /openbmc/linux/include/linux/pstore_ram.h (revision ebd09753)
1 /*
2  * Copyright (C) 2010 Marco Stornelli <marco.stornelli@gmail.com>
3  * Copyright (C) 2011 Kees Cook <keescook@chromium.org>
4  * Copyright (C) 2011 Google, Inc.
5  *
6  * This software is licensed under the terms of the GNU General Public
7  * License version 2, as published by the Free Software Foundation, and
8  * may be copied, distributed, and modified under those terms.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  */
16 
17 #ifndef __LINUX_PSTORE_RAM_H__
18 #define __LINUX_PSTORE_RAM_H__
19 
20 #include <linux/compiler.h>
21 #include <linux/device.h>
22 #include <linux/init.h>
23 #include <linux/kernel.h>
24 #include <linux/list.h>
25 #include <linux/types.h>
26 
27 /*
28  * Choose whether access to the RAM zone requires locking or not.  If a zone
29  * can be written to from different CPUs like with ftrace for example, then
30  * PRZ_FLAG_NO_LOCK is used. For all other cases, locking is required.
31  */
32 #define PRZ_FLAG_NO_LOCK	BIT(0)
33 
34 struct persistent_ram_buffer;
35 struct rs_control;
36 
37 struct persistent_ram_ecc_info {
38 	int block_size;
39 	int ecc_size;
40 	int symsize;
41 	int poly;
42 	uint16_t *par;
43 };
44 
45 struct persistent_ram_zone {
46 	phys_addr_t paddr;
47 	size_t size;
48 	void *vaddr;
49 	char *label;
50 	struct persistent_ram_buffer *buffer;
51 	size_t buffer_size;
52 	u32 flags;
53 	raw_spinlock_t buffer_lock;
54 
55 	/* ECC correction */
56 	char *par_buffer;
57 	char *par_header;
58 	struct rs_control *rs_decoder;
59 	int corrected_bytes;
60 	int bad_blocks;
61 	struct persistent_ram_ecc_info ecc_info;
62 
63 	char *old_log;
64 	size_t old_log_size;
65 };
66 
67 struct persistent_ram_zone *persistent_ram_new(phys_addr_t start, size_t size,
68 			u32 sig, struct persistent_ram_ecc_info *ecc_info,
69 			unsigned int memtype, u32 flags, char *label);
70 void persistent_ram_free(struct persistent_ram_zone *prz);
71 void persistent_ram_zap(struct persistent_ram_zone *prz);
72 
73 int persistent_ram_write(struct persistent_ram_zone *prz, const void *s,
74 			 unsigned int count);
75 int persistent_ram_write_user(struct persistent_ram_zone *prz,
76 			      const void __user *s, unsigned int count);
77 
78 void persistent_ram_save_old(struct persistent_ram_zone *prz);
79 size_t persistent_ram_old_size(struct persistent_ram_zone *prz);
80 void *persistent_ram_old(struct persistent_ram_zone *prz);
81 void persistent_ram_free_old(struct persistent_ram_zone *prz);
82 ssize_t persistent_ram_ecc_string(struct persistent_ram_zone *prz,
83 	char *str, size_t len);
84 
85 /*
86  * Ramoops platform data
87  * @mem_size	memory size for ramoops
88  * @mem_address	physical memory address to contain ramoops
89  */
90 
91 #define RAMOOPS_FLAG_FTRACE_PER_CPU	BIT(0)
92 
93 struct ramoops_platform_data {
94 	unsigned long	mem_size;
95 	phys_addr_t	mem_address;
96 	unsigned int	mem_type;
97 	unsigned long	record_size;
98 	unsigned long	console_size;
99 	unsigned long	ftrace_size;
100 	unsigned long	pmsg_size;
101 	int		dump_oops;
102 	u32		flags;
103 	struct persistent_ram_ecc_info ecc_info;
104 };
105 
106 #endif
107