1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
|
/*
* Copyright (C) 2015 Spreadtrum Communications Inc.
*
* This software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
* may be copied, distributed, and modified under those terms.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/module.h>
#include <linux/memblock.h>
#include <linux/io.h>
#include <linux/proc_fs.h>
#define PROC_DUMP_PARENT "bootloader"
#define PROC_DUMP "log_buf"
static unsigned int log_start = ~0x1;
static unsigned int log_size = ~0x1;
static int __init set_ram_range(char *str)
{
if (get_option(&str, &log_start) == 2)
get_option(&str, &log_size);
return 1;
}
__setup("boot_ram_log=", set_ram_range);
static int log_buf_open(struct inode *inode, struct file *filp)
{
void *base;
/* determine the ram area is valid or not. */
if (!valid_phys_addr_range(log_start, log_size)
|| !memblock_is_region_reserved(log_start, log_size)) {
pr_err("%s: check memory range failed!\n", __func__);
return -EINVAL;
}
base = ioremap(log_start, log_size);
filp->private_data = base;
if (!base) {
pr_err("%s: remap error!\n", __func__);
return -ENOMEM;
}
return 0;
}
static int log_buf_release(struct inode *inode, struct file *filp)
{
void *base = filp->private_data;
if (base)
iounmap(base);
return 0;
}
static ssize_t log_buf_read(struct file *filp, char __user *buffer,
size_t len, loff_t *offset)
{
void *base = filp->private_data;
if (!base)
return -ENOMEM;
return simple_read_from_buffer(buffer, len, offset, base, log_size);
}
static int log_buf_mmap(struct file *filp, struct vm_area_struct *vma)
{
vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
return vm_iomap_memory(vma, log_start, log_size);
}
static const struct file_operations log_buf_fops = {
.owner = THIS_MODULE,
.read = log_buf_read,
.open = log_buf_open,
.mmap = log_buf_mmap,
.release = log_buf_release,
};
static int __init uboot_log_dump(void)
{
int err;
struct proc_dir_entry *entry_parent, *entry_dump;
entry_parent = proc_mkdir("bootloader", NULL);
if (!entry_parent) {
pr_err("u-boot log dump: create proc file failed\n");
return -ENOMEM;
}
/* other user is NOT permitted to dump buffer */
entry_dump = proc_create_data(PROC_DUMP, S_IRUSR, entry_parent,
&log_buf_fops, NULL);
err = entry_dump ? 0 : -ENOMEM;
return err;
}
module_init(uboot_log_dump);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Spreadtrum U-boot log dump support");
|
