1/* SPDX-License-Identifier: GPL-2.0-only */
  2/*
  3 * Copyright (C) 2010 Marco Stornelli <marco.stornelli@gmail.com>
  4 * Copyright (C) 2011 Kees Cook <keescook@chromium.org>
  5 * Copyright (C) 2011 Google, Inc.
  6 */
  7
  8#ifndef __LINUX_PSTORE_RAM_H__
  9#define __LINUX_PSTORE_RAM_H__
 10
 11#include <linux/compiler.h>
 12#include <linux/device.h>
 13#include <linux/init.h>
 14#include <linux/kernel.h>
 15#include <linux/list.h>
 16#include <linux/pstore.h>
 17#include <linux/types.h>
 18
 19/*
 20 * Choose whether access to the RAM zone requires locking or not.  If a zone
 21 * can be written to from different CPUs like with ftrace for example, then
 22 * PRZ_FLAG_NO_LOCK is used. For all other cases, locking is required.
 23 */
 24#define PRZ_FLAG_NO_LOCK	BIT(0)
 25/*
 26 * If a PRZ should only have a single-boot lifetime, this marks it as
 27 * getting wiped after its contents get copied out after boot.
 28 */
 29#define PRZ_FLAG_ZAP_OLD	BIT(1)
 30
 31struct persistent_ram_buffer;
 32struct rs_control;
 33
 34struct persistent_ram_ecc_info {
 35	int block_size;
 36	int ecc_size;
 37	int symsize;
 38	int poly;
 39	uint16_t *par;
 40};
 41
 42/**
 43 * struct persistent_ram_zone - Details of a persistent RAM zone (PRZ)
 44 *                              used as a pstore backend
 45 *
 46 * @paddr:	physical address of the mapped RAM area
 47 * @size:	size of mapping
 48 * @label:	unique name of this PRZ
 49 * @type:	frontend type for this PRZ
 50 * @flags:	holds PRZ_FLAGS_* bits
 51 *
 52 * @buffer_lock:
 53 *	locks access to @buffer "size" bytes and "start" offset
 54 * @buffer:
 55 *	pointer to actual RAM area managed by this PRZ
 56 * @buffer_size:
 57 *	bytes in @buffer->data (not including any trailing ECC bytes)
 58 *
 59 * @par_buffer:
 60 *	pointer into @buffer->data containing ECC bytes for @buffer->data
 61 * @par_header:
 62 *	pointer into @buffer->data containing ECC bytes for @buffer header
 63 *	(i.e. all fields up to @data)
 64 * @rs_decoder:
 65 *	RSLIB instance for doing ECC calculations
 66 * @corrected_bytes:
 67 *	ECC corrected bytes accounting since boot
 68 * @bad_blocks:
 69 *	ECC uncorrectable bytes accounting since boot
 70 * @ecc_info:
 71 *	ECC configuration details
 72 *
 73 * @old_log:
 74 *	saved copy of @buffer->data prior to most recent wipe
 75 * @old_log_size:
 76 *	bytes contained in @old_log
 77 *
 78 */
 79struct persistent_ram_zone {
 80	phys_addr_t paddr;
 81	size_t size;
 82	void *vaddr;
 83	char *label;
 84	enum pstore_type_id type;
 85	u32 flags;
 86
 87	raw_spinlock_t buffer_lock;
 88	struct persistent_ram_buffer *buffer;
 89	size_t buffer_size;
 90
 91	char *par_buffer;
 92	char *par_header;
 93	struct rs_control *rs_decoder;
 94	int corrected_bytes;
 95	int bad_blocks;
 96	struct persistent_ram_ecc_info ecc_info;
 97
 98	char *old_log;
 99	size_t old_log_size;
100};
101
102struct persistent_ram_zone *persistent_ram_new(phys_addr_t start, size_t size,
103			u32 sig, struct persistent_ram_ecc_info *ecc_info,
104			unsigned int memtype, u32 flags, char *label);
105void persistent_ram_free(struct persistent_ram_zone *prz);
106void persistent_ram_zap(struct persistent_ram_zone *prz);
107
108int persistent_ram_write(struct persistent_ram_zone *prz, const void *s,
109			 unsigned int count);
110int persistent_ram_write_user(struct persistent_ram_zone *prz,
111			      const void __user *s, unsigned int count);
112
113void persistent_ram_save_old(struct persistent_ram_zone *prz);
114size_t persistent_ram_old_size(struct persistent_ram_zone *prz);
115void *persistent_ram_old(struct persistent_ram_zone *prz);
116void persistent_ram_free_old(struct persistent_ram_zone *prz);
117ssize_t persistent_ram_ecc_string(struct persistent_ram_zone *prz,
118	char *str, size_t len);
119
120/*
121 * Ramoops platform data
122 * @mem_size	memory size for ramoops
123 * @mem_address	physical memory address to contain ramoops
124 */
125
126#define RAMOOPS_FLAG_FTRACE_PER_CPU	BIT(0)
127
128struct ramoops_platform_data {
129	unsigned long	mem_size;
130	phys_addr_t	mem_address;
131	unsigned int	mem_type;
132	unsigned long	record_size;
133	unsigned long	console_size;
134	unsigned long	ftrace_size;
135	unsigned long	pmsg_size;
136	int		max_reason;
137	u32		flags;
138	struct persistent_ram_ecc_info ecc_info;
139};
140
141#endif