1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Copyright (C) 2015 Imagination Technologies
4 * Author: Paul Burton <paul.burton@mips.com>
5 */
6
7 #include <asm/bcache.h>
8 #include <asm/debug.h>
9 #include <linux/uaccess.h>
10 #include <linux/debugfs.h>
11 #include <linux/init.h>
12
13 static ssize_t sc_prefetch_read(struct file *file, char __user *user_buf,
14 size_t count, loff_t *ppos)
15 {
16 bool enabled = bc_prefetch_is_enabled();
17 char buf[3];
18
19 buf[0] = enabled ? 'Y' : 'N';
20 buf[1] = '\n';
21 buf[2] = 0;
22
23 return simple_read_from_buffer(user_buf, count, ppos, buf, 2);
24 }
25
26 static ssize_t sc_prefetch_write(struct file *file,
27 const char __user *user_buf,
28 size_t count, loff_t *ppos)
29 {
30 bool enabled;
31 int err;
32
33 err = kstrtobool_from_user(user_buf, count, &enabled);
34 if (err)
35 return err;
36
37 if (enabled)
38 bc_prefetch_enable();
39 else
40 bc_prefetch_disable();
41
42 return count;
43 }
44
45 static const struct file_operations sc_prefetch_fops = {
46 .open = simple_open,
47 .llseek = default_llseek,
48 .read = sc_prefetch_read,
49 .write = sc_prefetch_write,
50 };
51
52 static int __init sc_debugfs_init(void)
53 {
54 struct dentry *dir;
55
56 dir = debugfs_create_dir("l2cache", mips_debugfs_dir);
57 debugfs_create_file("prefetch", S_IRUGO | S_IWUSR, dir, NULL,
58 &sc_prefetch_fops);
59 return 0;
60 }
61 late_initcall(sc_debugfs_init);
62
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