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 
sc_prefetch_read(struct file * file,char __user * user_buf,size_t count,loff_t * ppos)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 
sc_prefetch_write(struct file * file,const char __user * user_buf,size_t count,loff_t * ppos)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 
sc_debugfs_init(void)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