^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0-or-later
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * Watchdog for the 7101 PMU version found in the ALi M1535 chipsets
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) #include <linux/module.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) #include <linux/moduleparam.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include <linux/types.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/miscdevice.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include <linux/watchdog.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #include <linux/ioport.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) #include <linux/notifier.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) #include <linux/reboot.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) #include <linux/init.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) #include <linux/fs.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) #include <linux/pci.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) #include <linux/uaccess.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) #include <linux/io.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) #define WATCHDOG_NAME "ALi_M1535"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) #define WATCHDOG_TIMEOUT 60 /* 60 sec default timeout */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) /* internal variables */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) static unsigned long ali_is_open;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) static char ali_expect_release;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) static struct pci_dev *ali_pci;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) static u32 ali_timeout_bits; /* stores the computed timeout */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) static DEFINE_SPINLOCK(ali_lock); /* Guards the hardware */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) /* module parameters */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) static int timeout = WATCHDOG_TIMEOUT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) module_param(timeout, int, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) MODULE_PARM_DESC(timeout,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) "Watchdog timeout in seconds. (0 < timeout < 18000, default="
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) __MODULE_STRING(WATCHDOG_TIMEOUT) ")");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) static bool nowayout = WATCHDOG_NOWAYOUT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) module_param(nowayout, bool, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) MODULE_PARM_DESC(nowayout,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) "Watchdog cannot be stopped once started (default="
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) * ali_start - start watchdog countdown
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) * Starts the timer running providing the timer has a counter
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) * configuration set.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) static void ali_start(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) u32 val;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) spin_lock(&ali_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) pci_read_config_dword(ali_pci, 0xCC, &val);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) val &= ~0x3F; /* Mask count */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) val |= (1 << 25) | ali_timeout_bits;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) pci_write_config_dword(ali_pci, 0xCC, val);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) spin_unlock(&ali_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) * ali_stop - stop the timer countdown
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) * Stop the ALi watchdog countdown
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) static void ali_stop(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) u32 val;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) spin_lock(&ali_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) pci_read_config_dword(ali_pci, 0xCC, &val);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) val &= ~0x3F; /* Mask count to zero (disabled) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) val &= ~(1 << 25); /* and for safety mask the reset enable */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) pci_write_config_dword(ali_pci, 0xCC, val);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) spin_unlock(&ali_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) * ali_keepalive - send a keepalive to the watchdog
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) * Send a keepalive to the timer (actually we restart the timer).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) static void ali_keepalive(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) ali_start();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) * ali_settimer - compute the timer reload value
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) * @t: time in seconds
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) * Computes the timeout values needed
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) static int ali_settimer(int t)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) if (t < 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) else if (t < 60)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) ali_timeout_bits = t|(1 << 6);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) else if (t < 3600)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) ali_timeout_bits = (t / 60)|(1 << 7);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) else if (t < 18000)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) ali_timeout_bits = (t / 300)|(1 << 6)|(1 << 7);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) timeout = t;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) * /dev/watchdog handling
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) * ali_write - writes to ALi watchdog
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) * @file: file from VFS
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) * @data: user address of data
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) * @len: length of data
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) * @ppos: pointer to the file offset
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) * Handle a write to the ALi watchdog. Writing to the file pings
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) * the watchdog and resets it. Writing the magic 'V' sequence allows
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) * the next close to turn off the watchdog.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) static ssize_t ali_write(struct file *file, const char __user *data,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) size_t len, loff_t *ppos)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) /* See if we got the magic character 'V' and reload the timer */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) if (len) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) if (!nowayout) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) size_t i;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) /* note: just in case someone wrote the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) magic character five months ago... */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) ali_expect_release = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) /* scan to see whether or not we got
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) the magic character */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) for (i = 0; i != len; i++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) char c;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) if (get_user(c, data + i))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) return -EFAULT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) if (c == 'V')
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) ali_expect_release = 42;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) /* someone wrote to us, we should reload the timer */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) ali_start();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) return len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) * ali_ioctl - handle watchdog ioctls
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) * @file: VFS file pointer
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) * @cmd: ioctl number
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) * @arg: arguments to the ioctl
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) * Handle the watchdog ioctls supported by the ALi driver. Really
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) * we want an extension to enable irq ack monitoring and the like
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) static long ali_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) void __user *argp = (void __user *)arg;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) int __user *p = argp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) static const struct watchdog_info ident = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) .options = WDIOF_KEEPALIVEPING |
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) WDIOF_SETTIMEOUT |
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) WDIOF_MAGICCLOSE,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) .firmware_version = 0,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) .identity = "ALi M1535 WatchDog Timer",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) switch (cmd) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) case WDIOC_GETSUPPORT:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) case WDIOC_GETSTATUS:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) case WDIOC_GETBOOTSTATUS:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) return put_user(0, p);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) case WDIOC_SETOPTIONS:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) int new_options, retval = -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) if (get_user(new_options, p))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) return -EFAULT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201) if (new_options & WDIOS_DISABLECARD) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) ali_stop();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) retval = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205) if (new_options & WDIOS_ENABLECARD) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) ali_start();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207) retval = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209) return retval;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211) case WDIOC_KEEPALIVE:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212) ali_keepalive();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) case WDIOC_SETTIMEOUT:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216) int new_timeout;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217) if (get_user(new_timeout, p))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218) return -EFAULT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219) if (ali_settimer(new_timeout))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 220) return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 221) ali_keepalive();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 222) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 223) fallthrough;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 224) case WDIOC_GETTIMEOUT:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 225) return put_user(timeout, p);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 226) default:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 227) return -ENOTTY;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 228) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 229) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 230)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 231) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 232) * ali_open - handle open of ali watchdog
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 233) * @inode: inode from VFS
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 234) * @file: file from VFS
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 235) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 236) * Open the ALi watchdog device. Ensure only one person opens it
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 237) * at a time. Also start the watchdog running.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 238) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 239)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 240) static int ali_open(struct inode *inode, struct file *file)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 241) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 242) /* /dev/watchdog can only be opened once */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 243) if (test_and_set_bit(0, &ali_is_open))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 244) return -EBUSY;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 245)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 246) /* Activate */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 247) ali_start();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 248) return stream_open(inode, file);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 249) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 250)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 251) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 252) * ali_release - close an ALi watchdog
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 253) * @inode: inode from VFS
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 254) * @file: file from VFS
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 255) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 256) * Close the ALi watchdog device. Actual shutdown of the timer
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 257) * only occurs if the magic sequence has been set.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 258) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 259)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 260) static int ali_release(struct inode *inode, struct file *file)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 261) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 262) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 263) * Shut off the timer.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 264) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 265) if (ali_expect_release == 42)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 266) ali_stop();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 267) else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 268) pr_crit("Unexpected close, not stopping watchdog!\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 269) ali_keepalive();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 270) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 271) clear_bit(0, &ali_is_open);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 272) ali_expect_release = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 273) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 274) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 275)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 276) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 277) * ali_notify_sys - System down notifier
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 278) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 279) * Notifier for system down
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 280) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 281)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 282)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 283) static int ali_notify_sys(struct notifier_block *this,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 284) unsigned long code, void *unused)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 285) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 286) if (code == SYS_DOWN || code == SYS_HALT)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 287) ali_stop(); /* Turn the WDT off */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 288) return NOTIFY_DONE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 289) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 290)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 291) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 292) * Data for PCI driver interface
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 293) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 294) * This data only exists for exporting the supported
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 295) * PCI ids via MODULE_DEVICE_TABLE. We do not actually
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 296) * register a pci_driver, because someone else might one day
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 297) * want to register another driver on the same PCI id.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 298) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 299)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 300) static const struct pci_device_id ali_pci_tbl[] __used = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 301) { PCI_VENDOR_ID_AL, 0x1533, PCI_ANY_ID, PCI_ANY_ID,},
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 302) { PCI_VENDOR_ID_AL, 0x1535, PCI_ANY_ID, PCI_ANY_ID,},
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 303) { 0, },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 304) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 305) MODULE_DEVICE_TABLE(pci, ali_pci_tbl);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 306)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 307) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 308) * ali_find_watchdog - find a 1535 and 7101
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 309) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 310) * Scans the PCI hardware for a 1535 series bridge and matching 7101
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 311) * watchdog device. This may be overtight but it is better to be safe
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 312) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 313)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 314) static int __init ali_find_watchdog(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 315) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 316) struct pci_dev *pdev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 317) u32 wdog;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 318)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 319) /* Check for a 1533/1535 series bridge */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 320) pdev = pci_get_device(PCI_VENDOR_ID_AL, 0x1535, NULL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 321) if (pdev == NULL)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 322) pdev = pci_get_device(PCI_VENDOR_ID_AL, 0x1533, NULL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 323) if (pdev == NULL)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 324) return -ENODEV;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 325) pci_dev_put(pdev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 326)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 327) /* Check for the a 7101 PMU */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 328) pdev = pci_get_device(PCI_VENDOR_ID_AL, 0x7101, NULL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 329) if (pdev == NULL)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 330) return -ENODEV;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 331)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 332) if (pci_enable_device(pdev)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 333) pci_dev_put(pdev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 334) return -EIO;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 335) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 336)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 337) ali_pci = pdev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 338)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 339) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 340) * Initialize the timer bits
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 341) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 342) pci_read_config_dword(pdev, 0xCC, &wdog);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 343)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 344) /* Timer bits */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 345) wdog &= ~0x3F;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 346) /* Issued events */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 347) wdog &= ~((1 << 27)|(1 << 26)|(1 << 25)|(1 << 24));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 348) /* No monitor bits */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 349) wdog &= ~((1 << 16)|(1 << 13)|(1 << 12)|(1 << 11)|(1 << 10)|(1 << 9));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 350)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 351) pci_write_config_dword(pdev, 0xCC, wdog);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 352)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 353) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 354) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 355)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 356) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 357) * Kernel Interfaces
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 358) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 359)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 360) static const struct file_operations ali_fops = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 361) .owner = THIS_MODULE,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 362) .llseek = no_llseek,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 363) .write = ali_write,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 364) .unlocked_ioctl = ali_ioctl,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 365) .compat_ioctl = compat_ptr_ioctl,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 366) .open = ali_open,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 367) .release = ali_release,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 368) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 369)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 370) static struct miscdevice ali_miscdev = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 371) .minor = WATCHDOG_MINOR,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 372) .name = "watchdog",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 373) .fops = &ali_fops,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 374) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 375)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 376) static struct notifier_block ali_notifier = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 377) .notifier_call = ali_notify_sys,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 378) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 379)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 380) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 381) * watchdog_init - module initialiser
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 382) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 383) * Scan for a suitable watchdog and if so initialize it. Return an error
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 384) * if we cannot, the error causes the module to unload
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 385) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 386)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 387) static int __init watchdog_init(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 388) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 389) int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 390)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 391) /* Check whether or not the hardware watchdog is there */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 392) if (ali_find_watchdog() != 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 393) return -ENODEV;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 394)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 395) /* Check that the timeout value is within it's range;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 396) if not reset to the default */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 397) if (timeout < 1 || timeout >= 18000) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 398) timeout = WATCHDOG_TIMEOUT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 399) pr_info("timeout value must be 0 < timeout < 18000, using %d\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 400) timeout);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 401) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 402)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 403) /* Calculate the watchdog's timeout */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 404) ali_settimer(timeout);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 405)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 406) ret = register_reboot_notifier(&ali_notifier);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 407) if (ret != 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 408) pr_err("cannot register reboot notifier (err=%d)\n", ret);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 409) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 410) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 411)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 412) ret = misc_register(&ali_miscdev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 413) if (ret != 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 414) pr_err("cannot register miscdev on minor=%d (err=%d)\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 415) WATCHDOG_MINOR, ret);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 416) goto unreg_reboot;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 417) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 418)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 419) pr_info("initialized. timeout=%d sec (nowayout=%d)\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 420) timeout, nowayout);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 421)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 422) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 423) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 424) unreg_reboot:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 425) unregister_reboot_notifier(&ali_notifier);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 426) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 427) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 428)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 429) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 430) * watchdog_exit - module de-initialiser
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 431) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 432) * Called while unloading a successfully installed watchdog module.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 433) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 434)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 435) static void __exit watchdog_exit(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 436) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 437) /* Stop the timer before we leave */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 438) ali_stop();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 439)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 440) /* Deregister */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 441) misc_deregister(&ali_miscdev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 442) unregister_reboot_notifier(&ali_notifier);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 443) pci_dev_put(ali_pci);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 444) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 445)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 446) module_init(watchdog_init);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 447) module_exit(watchdog_exit);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 448)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 449) MODULE_AUTHOR("Alan Cox");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 450) MODULE_DESCRIPTION("ALi M1535 PMU Watchdog Timer driver");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 451) MODULE_LICENSE("GPL");
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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