2
0
mirror of https://github.com/edk2-porting/linux-next.git synced 2024-12-25 21:54:06 +08:00
linux-next/drivers/watchdog/alim7101_wdt.c
Linus Torvalds 0195c00244 Disintegrate and delete asm/system.h
-----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1.4.12 (GNU/Linux)
 
 iQIVAwUAT3NKzROxKuMESys7AQKElw/+JyDxJSlj+g+nymkx8IVVuU8CsEwNLgRk
 8KEnRfLhGtkXFLSJYWO6jzGo16F8Uqli1PdMFte/wagSv0285/HZaKlkkBVHdJ/m
 u40oSjgT013bBh6MQ0Oaf8pFezFUiQB5zPOA9QGaLVGDLXCmgqUgd7exaD5wRIwB
 ZmyItjZeAVnDfk1R+ZiNYytHAi8A5wSB+eFDCIQYgyulA1Igd1UnRtx+dRKbvc/m
 rWQ6KWbZHIdvP1ksd8wHHkrlUD2pEeJ8glJLsZUhMm/5oMf/8RmOCvmo8rvE/qwl
 eDQ1h4cGYlfjobxXZMHqAN9m7Jg2bI946HZjdb7/7oCeO6VW3FwPZ/Ic75p+wp45
 HXJTItufERYk6QxShiOKvA+QexnYwY0IT5oRP4DrhdVB/X9cl2MoaZHC+RbYLQy+
 /5VNZKi38iK4F9AbFamS7kd0i5QszA/ZzEzKZ6VMuOp3W/fagpn4ZJT1LIA3m4A9
 Q0cj24mqeyCfjysu0TMbPtaN+Yjeu1o1OFRvM8XffbZsp5bNzuTDEvviJ2NXw4vK
 4qUHulhYSEWcu9YgAZXvEWDEM78FXCkg2v/CrZXH5tyc95kUkMPcgG+QZBB5wElR
 FaOKpiC/BuNIGEf02IZQ4nfDxE90QwnDeoYeV+FvNj9UEOopJ5z5bMPoTHxm4cCD
 NypQthI85pc=
 =G9mT
 -----END PGP SIGNATURE-----

Merge tag 'split-asm_system_h-for-linus-20120328' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-asm_system

Pull "Disintegrate and delete asm/system.h" from David Howells:
 "Here are a bunch of patches to disintegrate asm/system.h into a set of
  separate bits to relieve the problem of circular inclusion
  dependencies.

  I've built all the working defconfigs from all the arches that I can
  and made sure that they don't break.

  The reason for these patches is that I recently encountered a circular
  dependency problem that came about when I produced some patches to
  optimise get_order() by rewriting it to use ilog2().

  This uses bitops - and on the SH arch asm/bitops.h drags in
  asm-generic/get_order.h by a circuituous route involving asm/system.h.

  The main difficulty seems to be asm/system.h.  It holds a number of
  low level bits with no/few dependencies that are commonly used (eg.
  memory barriers) and a number of bits with more dependencies that
  aren't used in many places (eg.  switch_to()).

  These patches break asm/system.h up into the following core pieces:

    (1) asm/barrier.h

        Move memory barriers here.  This already done for MIPS and Alpha.

    (2) asm/switch_to.h

        Move switch_to() and related stuff here.

    (3) asm/exec.h

        Move arch_align_stack() here.  Other process execution related bits
        could perhaps go here from asm/processor.h.

    (4) asm/cmpxchg.h

        Move xchg() and cmpxchg() here as they're full word atomic ops and
        frequently used by atomic_xchg() and atomic_cmpxchg().

    (5) asm/bug.h

        Move die() and related bits.

    (6) asm/auxvec.h

        Move AT_VECTOR_SIZE_ARCH here.

  Other arch headers are created as needed on a per-arch basis."

Fixed up some conflicts from other header file cleanups and moving code
around that has happened in the meantime, so David's testing is somewhat
weakened by that.  We'll find out anything that got broken and fix it..

* tag 'split-asm_system_h-for-linus-20120328' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-asm_system: (38 commits)
  Delete all instances of asm/system.h
  Remove all #inclusions of asm/system.h
  Add #includes needed to permit the removal of asm/system.h
  Move all declarations of free_initmem() to linux/mm.h
  Disintegrate asm/system.h for OpenRISC
  Split arch_align_stack() out from asm-generic/system.h
  Split the switch_to() wrapper out of asm-generic/system.h
  Move the asm-generic/system.h xchg() implementation to asm-generic/cmpxchg.h
  Create asm-generic/barrier.h
  Make asm-generic/cmpxchg.h #include asm-generic/cmpxchg-local.h
  Disintegrate asm/system.h for Xtensa
  Disintegrate asm/system.h for Unicore32 [based on ver #3, changed by gxt]
  Disintegrate asm/system.h for Tile
  Disintegrate asm/system.h for Sparc
  Disintegrate asm/system.h for SH
  Disintegrate asm/system.h for Score
  Disintegrate asm/system.h for S390
  Disintegrate asm/system.h for PowerPC
  Disintegrate asm/system.h for PA-RISC
  Disintegrate asm/system.h for MN10300
  ...
2012-03-28 15:58:21 -07:00

429 lines
10 KiB
C

/*
* ALi M7101 PMU Computer Watchdog Timer driver
*
* Based on w83877f_wdt.c by Scott Jennings <linuxdrivers@oro.net>
* and the Cobalt kernel WDT timer driver by Tim Hockin
* <thockin@cobaltnet.com>
*
* (c)2002 Steve Hill <steve@navaho.co.uk>
*
* This WDT driver is different from most other Linux WDT
* drivers in that the driver will ping the watchdog by itself,
* because this particular WDT has a very short timeout (1.6
* seconds) and it would be insane to count on any userspace
* daemon always getting scheduled within that time frame.
*
* Additions:
* Aug 23, 2004 - Added use_gpio module parameter for use on revision a1d PMUs
* found on very old cobalt hardware.
* -- Mike Waychison <michael.waychison@sun.com>
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/types.h>
#include <linux/timer.h>
#include <linux/miscdevice.h>
#include <linux/watchdog.h>
#include <linux/ioport.h>
#include <linux/notifier.h>
#include <linux/reboot.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/pci.h>
#include <linux/io.h>
#include <linux/uaccess.h>
#define WDT_ENABLE 0x9C
#define WDT_DISABLE 0x8C
#define ALI_7101_WDT 0x92
#define ALI_7101_GPIO 0x7D
#define ALI_7101_GPIO_O 0x7E
#define ALI_WDT_ARM 0x01
/*
* We're going to use a 1 second timeout.
* If we reset the watchdog every ~250ms we should be safe. */
#define WDT_INTERVAL (HZ/4+1)
/*
* We must not require too good response from the userspace daemon.
* Here we require the userspace daemon to send us a heartbeat
* char to /dev/watchdog every 30 seconds.
*/
#define WATCHDOG_TIMEOUT 30 /* 30 sec default timeout */
/* in seconds, will be multiplied by HZ to get seconds to wait for a ping */
static int timeout = WATCHDOG_TIMEOUT;
module_param(timeout, int, 0);
MODULE_PARM_DESC(timeout,
"Watchdog timeout in seconds. (1<=timeout<=3600, default="
__MODULE_STRING(WATCHDOG_TIMEOUT) ")");
static int use_gpio; /* Use the pic (for a1d revision alim7101) */
module_param(use_gpio, int, 0);
MODULE_PARM_DESC(use_gpio,
"Use the gpio watchdog (required by old cobalt boards).");
static void wdt_timer_ping(unsigned long);
static DEFINE_TIMER(timer, wdt_timer_ping, 0, 1);
static unsigned long next_heartbeat;
static unsigned long wdt_is_open;
static char wdt_expect_close;
static struct pci_dev *alim7101_pmu;
static bool nowayout = WATCHDOG_NOWAYOUT;
module_param(nowayout, bool, 0);
MODULE_PARM_DESC(nowayout,
"Watchdog cannot be stopped once started (default="
__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
/*
* Whack the dog
*/
static void wdt_timer_ping(unsigned long data)
{
/* If we got a heartbeat pulse within the WDT_US_INTERVAL
* we agree to ping the WDT
*/
char tmp;
if (time_before(jiffies, next_heartbeat)) {
/* Ping the WDT (this is actually a disarm/arm sequence) */
pci_read_config_byte(alim7101_pmu, 0x92, &tmp);
pci_write_config_byte(alim7101_pmu,
ALI_7101_WDT, (tmp & ~ALI_WDT_ARM));
pci_write_config_byte(alim7101_pmu,
ALI_7101_WDT, (tmp | ALI_WDT_ARM));
if (use_gpio) {
pci_read_config_byte(alim7101_pmu,
ALI_7101_GPIO_O, &tmp);
pci_write_config_byte(alim7101_pmu,
ALI_7101_GPIO_O, tmp | 0x20);
pci_write_config_byte(alim7101_pmu,
ALI_7101_GPIO_O, tmp & ~0x20);
}
} else {
pr_warn("Heartbeat lost! Will not ping the watchdog\n");
}
/* Re-set the timer interval */
mod_timer(&timer, jiffies + WDT_INTERVAL);
}
/*
* Utility routines
*/
static void wdt_change(int writeval)
{
char tmp;
pci_read_config_byte(alim7101_pmu, ALI_7101_WDT, &tmp);
if (writeval == WDT_ENABLE) {
pci_write_config_byte(alim7101_pmu,
ALI_7101_WDT, (tmp | ALI_WDT_ARM));
if (use_gpio) {
pci_read_config_byte(alim7101_pmu,
ALI_7101_GPIO_O, &tmp);
pci_write_config_byte(alim7101_pmu,
ALI_7101_GPIO_O, tmp & ~0x20);
}
} else {
pci_write_config_byte(alim7101_pmu,
ALI_7101_WDT, (tmp & ~ALI_WDT_ARM));
if (use_gpio) {
pci_read_config_byte(alim7101_pmu,
ALI_7101_GPIO_O, &tmp);
pci_write_config_byte(alim7101_pmu,
ALI_7101_GPIO_O, tmp | 0x20);
}
}
}
static void wdt_startup(void)
{
next_heartbeat = jiffies + (timeout * HZ);
/* We must enable before we kick off the timer in case the timer
occurs as we ping it */
wdt_change(WDT_ENABLE);
/* Start the timer */
mod_timer(&timer, jiffies + WDT_INTERVAL);
pr_info("Watchdog timer is now enabled\n");
}
static void wdt_turnoff(void)
{
/* Stop the timer */
del_timer_sync(&timer);
wdt_change(WDT_DISABLE);
pr_info("Watchdog timer is now disabled...\n");
}
static void wdt_keepalive(void)
{
/* user land ping */
next_heartbeat = jiffies + (timeout * HZ);
}
/*
* /dev/watchdog handling
*/
static ssize_t fop_write(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
/* See if we got the magic character 'V' and reload the timer */
if (count) {
if (!nowayout) {
size_t ofs;
/* note: just in case someone wrote the magic character
* five months ago... */
wdt_expect_close = 0;
/* now scan */
for (ofs = 0; ofs != count; ofs++) {
char c;
if (get_user(c, buf + ofs))
return -EFAULT;
if (c == 'V')
wdt_expect_close = 42;
}
}
/* someone wrote to us, we should restart timer */
wdt_keepalive();
}
return count;
}
static int fop_open(struct inode *inode, struct file *file)
{
/* Just in case we're already talking to someone... */
if (test_and_set_bit(0, &wdt_is_open))
return -EBUSY;
/* Good, fire up the show */
wdt_startup();
return nonseekable_open(inode, file);
}
static int fop_close(struct inode *inode, struct file *file)
{
if (wdt_expect_close == 42)
wdt_turnoff();
else {
/* wim: shouldn't there be a: del_timer(&timer); */
pr_crit("device file closed unexpectedly. Will not stop the WDT!\n");
}
clear_bit(0, &wdt_is_open);
wdt_expect_close = 0;
return 0;
}
static long fop_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
void __user *argp = (void __user *)arg;
int __user *p = argp;
static const struct watchdog_info ident = {
.options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT
| WDIOF_MAGICCLOSE,
.firmware_version = 1,
.identity = "ALiM7101",
};
switch (cmd) {
case WDIOC_GETSUPPORT:
return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0;
case WDIOC_GETSTATUS:
case WDIOC_GETBOOTSTATUS:
return put_user(0, p);
case WDIOC_SETOPTIONS:
{
int new_options, retval = -EINVAL;
if (get_user(new_options, p))
return -EFAULT;
if (new_options & WDIOS_DISABLECARD) {
wdt_turnoff();
retval = 0;
}
if (new_options & WDIOS_ENABLECARD) {
wdt_startup();
retval = 0;
}
return retval;
}
case WDIOC_KEEPALIVE:
wdt_keepalive();
return 0;
case WDIOC_SETTIMEOUT:
{
int new_timeout;
if (get_user(new_timeout, p))
return -EFAULT;
/* arbitrary upper limit */
if (new_timeout < 1 || new_timeout > 3600)
return -EINVAL;
timeout = new_timeout;
wdt_keepalive();
/* Fall through */
}
case WDIOC_GETTIMEOUT:
return put_user(timeout, p);
default:
return -ENOTTY;
}
}
static const struct file_operations wdt_fops = {
.owner = THIS_MODULE,
.llseek = no_llseek,
.write = fop_write,
.open = fop_open,
.release = fop_close,
.unlocked_ioctl = fop_ioctl,
};
static struct miscdevice wdt_miscdev = {
.minor = WATCHDOG_MINOR,
.name = "watchdog",
.fops = &wdt_fops,
};
/*
* Notifier for system down
*/
static int wdt_notify_sys(struct notifier_block *this,
unsigned long code, void *unused)
{
if (code == SYS_DOWN || code == SYS_HALT)
wdt_turnoff();
if (code == SYS_RESTART) {
/*
* Cobalt devices have no way of rebooting themselves other
* than getting the watchdog to pull reset, so we restart the
* watchdog on reboot with no heartbeat
*/
wdt_change(WDT_ENABLE);
pr_info("Watchdog timer is now enabled with no heartbeat - should reboot in ~1 second\n");
}
return NOTIFY_DONE;
}
/*
* The WDT needs to learn about soft shutdowns in order to
* turn the timebomb registers off.
*/
static struct notifier_block wdt_notifier = {
.notifier_call = wdt_notify_sys,
};
static void __exit alim7101_wdt_unload(void)
{
wdt_turnoff();
/* Deregister */
misc_deregister(&wdt_miscdev);
unregister_reboot_notifier(&wdt_notifier);
pci_dev_put(alim7101_pmu);
}
static int __init alim7101_wdt_init(void)
{
int rc = -EBUSY;
struct pci_dev *ali1543_south;
char tmp;
pr_info("Steve Hill <steve@navaho.co.uk>\n");
alim7101_pmu = pci_get_device(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M7101,
NULL);
if (!alim7101_pmu) {
pr_info("ALi M7101 PMU not present - WDT not set\n");
return -EBUSY;
}
/* Set the WDT in the PMU to 1 second */
pci_write_config_byte(alim7101_pmu, ALI_7101_WDT, 0x02);
ali1543_south = pci_get_device(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M1533,
NULL);
if (!ali1543_south) {
pr_info("ALi 1543 South-Bridge not present - WDT not set\n");
goto err_out;
}
pci_read_config_byte(ali1543_south, 0x5e, &tmp);
pci_dev_put(ali1543_south);
if ((tmp & 0x1e) == 0x00) {
if (!use_gpio) {
pr_info("Detected old alim7101 revision 'a1d'. If this is a cobalt board, set the 'use_gpio' module parameter.\n");
goto err_out;
}
nowayout = 1;
} else if ((tmp & 0x1e) != 0x12 && (tmp & 0x1e) != 0x00) {
pr_info("ALi 1543 South-Bridge does not have the correct revision number (???1001?) - WDT not set\n");
goto err_out;
}
if (timeout < 1 || timeout > 3600) {
/* arbitrary upper limit */
timeout = WATCHDOG_TIMEOUT;
pr_info("timeout value must be 1 <= x <= 3600, using %d\n",
timeout);
}
rc = register_reboot_notifier(&wdt_notifier);
if (rc) {
pr_err("cannot register reboot notifier (err=%d)\n", rc);
goto err_out;
}
rc = misc_register(&wdt_miscdev);
if (rc) {
pr_err("cannot register miscdev on minor=%d (err=%d)\n",
wdt_miscdev.minor, rc);
goto err_out_reboot;
}
if (nowayout)
__module_get(THIS_MODULE);
pr_info("WDT driver for ALi M7101 initialised. timeout=%d sec (nowayout=%d)\n",
timeout, nowayout);
return 0;
err_out_reboot:
unregister_reboot_notifier(&wdt_notifier);
err_out:
pci_dev_put(alim7101_pmu);
return rc;
}
module_init(alim7101_wdt_init);
module_exit(alim7101_wdt_unload);
static DEFINE_PCI_DEVICE_TABLE(alim7101_pci_tbl) __used = {
{ PCI_DEVICE(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M1533) },
{ PCI_DEVICE(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M7101) },
{ }
};
MODULE_DEVICE_TABLE(pci, alim7101_pci_tbl);
MODULE_AUTHOR("Steve Hill");
MODULE_DESCRIPTION("ALi M7101 PMU Computer Watchdog Timer driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);