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