Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Watchdog driver for the SA11x0/PXA2xx |
| 3 | * |
Wim Van Sebroeck | 143a2e5 | 2009-03-18 08:35:09 +0000 | [diff] [blame] | 4 | * (c) Copyright 2000 Oleg Drokin <green@crimea.edu> |
| 5 | * Based on SoftDog driver by Alan Cox <alan@lxorguk.ukuu.org.uk> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 6 | * |
| 7 | * This program is free software; you can redistribute it and/or |
| 8 | * modify it under the terms of the GNU General Public License |
| 9 | * as published by the Free Software Foundation; either version |
| 10 | * 2 of the License, or (at your option) any later version. |
| 11 | * |
| 12 | * Neither Oleg Drokin nor iXcelerator.com admit liability nor provide |
| 13 | * warranty for any of this software. This material is provided |
| 14 | * "AS-IS" and at no charge. |
| 15 | * |
| 16 | * (c) Copyright 2000 Oleg Drokin <green@crimea.edu> |
| 17 | * |
Wim Van Sebroeck | 143a2e5 | 2009-03-18 08:35:09 +0000 | [diff] [blame] | 18 | * 27/11/2000 Initial release |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 19 | */ |
Joe Perches | 27c766a | 2012-02-15 15:06:19 -0800 | [diff] [blame] | 20 | |
| 21 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| 22 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 23 | #include <linux/module.h> |
| 24 | #include <linux/moduleparam.h> |
| 25 | #include <linux/types.h> |
| 26 | #include <linux/kernel.h> |
| 27 | #include <linux/fs.h> |
| 28 | #include <linux/miscdevice.h> |
| 29 | #include <linux/watchdog.h> |
| 30 | #include <linux/init.h> |
Rob Herring | 23019a7 | 2012-03-20 14:33:19 -0500 | [diff] [blame] | 31 | #include <linux/io.h> |
Jiri Slaby | 1977f03 | 2007-10-18 23:40:25 -0700 | [diff] [blame] | 32 | #include <linux/bitops.h> |
Alan Cox | f19e031 | 2008-05-19 14:08:05 +0100 | [diff] [blame] | 33 | #include <linux/uaccess.h> |
Russell King | 87c5257 | 2008-11-29 17:35:51 +0000 | [diff] [blame] | 34 | #include <linux/timex.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 35 | |
| 36 | #ifdef CONFIG_ARCH_PXA |
Eric Miao | 5bf3df3 | 2009-01-20 11:04:16 +0800 | [diff] [blame] | 37 | #include <mach/regs-ost.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 38 | #endif |
| 39 | |
Russell King | afd2fc0 | 2008-08-07 11:05:25 +0100 | [diff] [blame] | 40 | #include <mach/reset.h> |
Russell King | a09e64f | 2008-08-05 16:14:15 +0100 | [diff] [blame] | 41 | #include <mach/hardware.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 42 | |
Eric Miao | 28a6238 | 2008-12-24 11:32:45 +0800 | [diff] [blame] | 43 | static unsigned long oscr_freq; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 44 | static unsigned long sa1100wdt_users; |
Raphael Assenat | a6f052e | 2009-06-29 13:56:52 -0400 | [diff] [blame] | 45 | static unsigned int pre_margin; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 46 | static int boot_status; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 47 | |
| 48 | /* |
| 49 | * Allow only one person to hold it open |
| 50 | */ |
| 51 | static int sa1100dog_open(struct inode *inode, struct file *file) |
| 52 | { |
Alan Cox | f19e031 | 2008-05-19 14:08:05 +0100 | [diff] [blame] | 53 | if (test_and_set_bit(1, &sa1100wdt_users)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 54 | return -EBUSY; |
| 55 | |
| 56 | /* Activate SA1100 Watchdog timer */ |
Russell King | 3169663 | 2012-06-06 11:42:36 +0100 | [diff] [blame] | 57 | writel_relaxed(readl_relaxed(OSCR) + pre_margin, OSMR3); |
| 58 | writel_relaxed(OSSR_M3, OSSR); |
| 59 | writel_relaxed(OWER_WME, OWER); |
| 60 | writel_relaxed(readl_relaxed(OIER) | OIER_E3, OIER); |
Wim Van Sebroeck | 6abe78b | 2007-07-24 21:38:37 +0000 | [diff] [blame] | 61 | return nonseekable_open(inode, file); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 62 | } |
| 63 | |
| 64 | /* |
Ian Campbell | 9bbd037 | 2005-08-03 20:34:52 +0100 | [diff] [blame] | 65 | * The watchdog cannot be disabled. |
| 66 | * |
| 67 | * Previous comments suggested that turning off the interrupt by |
| 68 | * clearing OIER[E3] would prevent the watchdog timing out but this |
| 69 | * does not appear to be true (at least on the PXA255). |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 70 | */ |
| 71 | static int sa1100dog_release(struct inode *inode, struct file *file) |
| 72 | { |
Joe Perches | 27c766a | 2012-02-15 15:06:19 -0800 | [diff] [blame] | 73 | pr_crit("Device closed - timer will not stop\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 74 | clear_bit(1, &sa1100wdt_users); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 75 | return 0; |
| 76 | } |
| 77 | |
Alan Cox | f19e031 | 2008-05-19 14:08:05 +0100 | [diff] [blame] | 78 | static ssize_t sa1100dog_write(struct file *file, const char __user *data, |
| 79 | size_t len, loff_t *ppos) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 80 | { |
Ian Campbell | 9bbd037 | 2005-08-03 20:34:52 +0100 | [diff] [blame] | 81 | if (len) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 82 | /* Refresh OSMR3 timer. */ |
Russell King | 3169663 | 2012-06-06 11:42:36 +0100 | [diff] [blame] | 83 | writel_relaxed(readl_relaxed(OSCR) + pre_margin, OSMR3); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 84 | return len; |
| 85 | } |
| 86 | |
Alan Cox | f19e031 | 2008-05-19 14:08:05 +0100 | [diff] [blame] | 87 | static const struct watchdog_info ident = { |
| 88 | .options = WDIOF_CARDRESET | WDIOF_SETTIMEOUT |
| 89 | | WDIOF_KEEPALIVEPING, |
Ian Campbell | 9bbd037 | 2005-08-03 20:34:52 +0100 | [diff] [blame] | 90 | .identity = "SA1100/PXA255 Watchdog", |
Raphael Assenat | a6f052e | 2009-06-29 13:56:52 -0400 | [diff] [blame] | 91 | .firmware_version = 1, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 92 | }; |
| 93 | |
Alan Cox | f19e031 | 2008-05-19 14:08:05 +0100 | [diff] [blame] | 94 | static long sa1100dog_ioctl(struct file *file, unsigned int cmd, |
| 95 | unsigned long arg) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 96 | { |
Samuel Tardieu | 795b89d | 2006-09-09 17:34:31 +0200 | [diff] [blame] | 97 | int ret = -ENOTTY; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 98 | int time; |
Ian Campbell | 3a69e57 | 2005-11-07 10:21:24 +0000 | [diff] [blame] | 99 | void __user *argp = (void __user *)arg; |
| 100 | int __user *p = argp; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 101 | |
| 102 | switch (cmd) { |
| 103 | case WDIOC_GETSUPPORT: |
Ian Campbell | 3a69e57 | 2005-11-07 10:21:24 +0000 | [diff] [blame] | 104 | ret = copy_to_user(argp, &ident, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 105 | sizeof(ident)) ? -EFAULT : 0; |
| 106 | break; |
| 107 | |
| 108 | case WDIOC_GETSTATUS: |
Ian Campbell | 3a69e57 | 2005-11-07 10:21:24 +0000 | [diff] [blame] | 109 | ret = put_user(0, p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 110 | break; |
| 111 | |
| 112 | case WDIOC_GETBOOTSTATUS: |
Ian Campbell | 3a69e57 | 2005-11-07 10:21:24 +0000 | [diff] [blame] | 113 | ret = put_user(boot_status, p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 114 | break; |
| 115 | |
Wim Van Sebroeck | 0c06090c | 2008-07-18 11:41:17 +0000 | [diff] [blame] | 116 | case WDIOC_KEEPALIVE: |
Russell King | 3169663 | 2012-06-06 11:42:36 +0100 | [diff] [blame] | 117 | writel_relaxed(readl_relaxed(OSCR) + pre_margin, OSMR3); |
Wim Van Sebroeck | 0c06090c | 2008-07-18 11:41:17 +0000 | [diff] [blame] | 118 | ret = 0; |
| 119 | break; |
| 120 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 121 | case WDIOC_SETTIMEOUT: |
Ian Campbell | 3a69e57 | 2005-11-07 10:21:24 +0000 | [diff] [blame] | 122 | ret = get_user(time, p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 123 | if (ret) |
| 124 | break; |
| 125 | |
Raphael Assenat | a6f052e | 2009-06-29 13:56:52 -0400 | [diff] [blame] | 126 | if (time <= 0 || (oscr_freq * (long long)time >= 0xffffffff)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 127 | ret = -EINVAL; |
| 128 | break; |
| 129 | } |
| 130 | |
Eric Miao | 28a6238 | 2008-12-24 11:32:45 +0800 | [diff] [blame] | 131 | pre_margin = oscr_freq * time; |
Russell King | 3169663 | 2012-06-06 11:42:36 +0100 | [diff] [blame] | 132 | writel_relaxed(readl_relaxed(OSCR) + pre_margin, OSMR3); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 133 | /*fall through*/ |
| 134 | |
| 135 | case WDIOC_GETTIMEOUT: |
Eric Miao | 28a6238 | 2008-12-24 11:32:45 +0800 | [diff] [blame] | 136 | ret = put_user(pre_margin / oscr_freq, p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 137 | break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 138 | } |
| 139 | return ret; |
| 140 | } |
| 141 | |
Alan Cox | f19e031 | 2008-05-19 14:08:05 +0100 | [diff] [blame] | 142 | static const struct file_operations sa1100dog_fops = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 143 | .owner = THIS_MODULE, |
| 144 | .llseek = no_llseek, |
| 145 | .write = sa1100dog_write, |
Alan Cox | f19e031 | 2008-05-19 14:08:05 +0100 | [diff] [blame] | 146 | .unlocked_ioctl = sa1100dog_ioctl, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 147 | .open = sa1100dog_open, |
| 148 | .release = sa1100dog_release, |
| 149 | }; |
| 150 | |
Alan Cox | f19e031 | 2008-05-19 14:08:05 +0100 | [diff] [blame] | 151 | static struct miscdevice sa1100dog_miscdev = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 152 | .minor = WATCHDOG_MINOR, |
Ian Campbell | 9bbd037 | 2005-08-03 20:34:52 +0100 | [diff] [blame] | 153 | .name = "watchdog", |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 154 | .fops = &sa1100dog_fops, |
| 155 | }; |
| 156 | |
| 157 | static int margin __initdata = 60; /* (secs) Default is 1 minute */ |
| 158 | |
| 159 | static int __init sa1100dog_init(void) |
| 160 | { |
| 161 | int ret; |
| 162 | |
Eric Miao | 28a6238 | 2008-12-24 11:32:45 +0800 | [diff] [blame] | 163 | oscr_freq = get_clock_tick_rate(); |
| 164 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 165 | /* |
| 166 | * Read the reset status, and save it for later. If |
| 167 | * we suspend, RCSR will be cleared, and the watchdog |
| 168 | * reset reason will be lost. |
| 169 | */ |
Eric Miao | 214c6a7 | 2008-07-29 14:39:34 +0800 | [diff] [blame] | 170 | boot_status = (reset_status & RESET_STATUS_WATCHDOG) ? |
| 171 | WDIOF_CARDRESET : 0; |
Eric Miao | 28a6238 | 2008-12-24 11:32:45 +0800 | [diff] [blame] | 172 | pre_margin = oscr_freq * margin; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 173 | |
| 174 | ret = misc_register(&sa1100dog_miscdev); |
| 175 | if (ret == 0) |
Joe Perches | 27c766a | 2012-02-15 15:06:19 -0800 | [diff] [blame] | 176 | pr_info("SA1100/PXA2xx Watchdog Timer: timer margin %d sec\n", |
| 177 | margin); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 178 | return ret; |
| 179 | } |
| 180 | |
| 181 | static void __exit sa1100dog_exit(void) |
| 182 | { |
| 183 | misc_deregister(&sa1100dog_miscdev); |
| 184 | } |
| 185 | |
| 186 | module_init(sa1100dog_init); |
| 187 | module_exit(sa1100dog_exit); |
| 188 | |
| 189 | MODULE_AUTHOR("Oleg Drokin <green@crimea.edu>"); |
| 190 | MODULE_DESCRIPTION("SA1100/PXA2xx Watchdog"); |
| 191 | |
| 192 | module_param(margin, int, 0); |
| 193 | MODULE_PARM_DESC(margin, "Watchdog margin in seconds (default 60s)"); |
| 194 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 195 | MODULE_LICENSE("GPL"); |
| 196 | MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); |