| 1 |
1275 |
phoenix |
Berkshire Products PC Watchdog Card
|
| 2 |
|
|
Support for ISA Cards Revision A and C
|
| 3 |
|
|
Documentation and Driver by Ken Hollis
|
| 4 |
|
|
|
| 5 |
|
|
The PC Watchdog is a card that offers the same type of functionality that
|
| 6 |
|
|
the WDT card does, only it doesn't require an IRQ to run. Furthermore,
|
| 7 |
|
|
the Revision C card allows you to monitor any IO Port to automatically
|
| 8 |
|
|
trigger the card into being reset. This way you can make the card
|
| 9 |
|
|
monitor hard drive status, or anything else you need.
|
| 10 |
|
|
|
| 11 |
|
|
The Watchdog Driver has one basic role: to talk to the card and send
|
| 12 |
|
|
signals to it so it doesn't reset your computer ... at least during
|
| 13 |
|
|
normal operation.
|
| 14 |
|
|
|
| 15 |
|
|
The Watchdog Driver will automatically find your watchdog card, and will
|
| 16 |
|
|
attach a running driver for use with that card. After the watchdog
|
| 17 |
|
|
drivers have initialized, you can then talk to the card using the PC
|
| 18 |
|
|
Watchdog program, available from http://ftp.bitgate.com/pcwd/.
|
| 19 |
|
|
|
| 20 |
|
|
I suggest putting a "watchdog -d" before the beginning of an fsck, and
|
| 21 |
|
|
a "watchdog -e -t 1" immediately after the end of an fsck. (Remember
|
| 22 |
|
|
to run the program with an "&" to run it in the background!)
|
| 23 |
|
|
|
| 24 |
|
|
If you want to write a program to be compatible with the PC Watchdog
|
| 25 |
|
|
driver, simply do the following:
|
| 26 |
|
|
|
| 27 |
|
|
-- Snippet of code --
|
| 28 |
|
|
/*
|
| 29 |
|
|
* Watchdog Driver Test Program
|
| 30 |
|
|
*/
|
| 31 |
|
|
|
| 32 |
|
|
#include
|
| 33 |
|
|
#include
|
| 34 |
|
|
#include
|
| 35 |
|
|
#include
|
| 36 |
|
|
#include
|
| 37 |
|
|
#include
|
| 38 |
|
|
#include
|
| 39 |
|
|
|
| 40 |
|
|
int fd;
|
| 41 |
|
|
|
| 42 |
|
|
/*
|
| 43 |
|
|
* This function simply sends an IOCTL to the driver, which in turn ticks
|
| 44 |
|
|
* the PC Watchdog card to reset its internal timer so it doesn't trigger
|
| 45 |
|
|
* a computer reset.
|
| 46 |
|
|
*/
|
| 47 |
|
|
void keep_alive(void)
|
| 48 |
|
|
{
|
| 49 |
|
|
int dummy;
|
| 50 |
|
|
|
| 51 |
|
|
ioctl(fd, WDIOC_KEEPALIVE, &dummy);
|
| 52 |
|
|
}
|
| 53 |
|
|
|
| 54 |
|
|
/*
|
| 55 |
|
|
* The main program. Run the program with "-d" to disable the card,
|
| 56 |
|
|
* or "-e" to enable the card.
|
| 57 |
|
|
*/
|
| 58 |
|
|
int main(int argc, char *argv[])
|
| 59 |
|
|
{
|
| 60 |
|
|
fd = open("/dev/watchdog", O_WRONLY);
|
| 61 |
|
|
|
| 62 |
|
|
if (fd == -1) {
|
| 63 |
|
|
fprintf(stderr, "Watchdog device not enabled.\n");
|
| 64 |
|
|
fflush(stderr);
|
| 65 |
|
|
exit(-1);
|
| 66 |
|
|
}
|
| 67 |
|
|
|
| 68 |
|
|
if (argc > 1) {
|
| 69 |
|
|
if (!strncasecmp(argv[1], "-d", 2)) {
|
| 70 |
|
|
ioctl(fd, WDIOC_SETOPTIONS, WDIOS_DISABLECARD);
|
| 71 |
|
|
fprintf(stderr, "Watchdog card disabled.\n");
|
| 72 |
|
|
fflush(stderr);
|
| 73 |
|
|
exit(0);
|
| 74 |
|
|
} else if (!strncasecmp(argv[1], "-e", 2)) {
|
| 75 |
|
|
ioctl(fd, WDIOC_SETOPTIONS, WDIOS_ENABLECARD);
|
| 76 |
|
|
fprintf(stderr, "Watchdog card enabled.\n");
|
| 77 |
|
|
fflush(stderr);
|
| 78 |
|
|
exit(0);
|
| 79 |
|
|
} else {
|
| 80 |
|
|
fprintf(stderr, "-d to disable, -e to enable.\n");
|
| 81 |
|
|
fprintf(stderr, "run by itself to tick the card.\n");
|
| 82 |
|
|
fflush(stderr);
|
| 83 |
|
|
exit(0);
|
| 84 |
|
|
}
|
| 85 |
|
|
} else {
|
| 86 |
|
|
fprintf(stderr, "Watchdog Ticking Away!\n");
|
| 87 |
|
|
fflush(stderr);
|
| 88 |
|
|
}
|
| 89 |
|
|
|
| 90 |
|
|
while(1) {
|
| 91 |
|
|
keep_alive();
|
| 92 |
|
|
sleep(1);
|
| 93 |
|
|
}
|
| 94 |
|
|
}
|
| 95 |
|
|
-- End snippet --
|
| 96 |
|
|
|
| 97 |
|
|
Other IOCTL functions include:
|
| 98 |
|
|
|
| 99 |
|
|
WDIOC_GETSUPPORT
|
| 100 |
|
|
This returns the support of the card itself. This
|
| 101 |
|
|
returns in structure "PCWDS" which returns:
|
| 102 |
|
|
options = WDIOS_TEMPPANIC
|
| 103 |
|
|
(This card supports temperature)
|
| 104 |
|
|
firmware_version = xxxx
|
| 105 |
|
|
(Firmware version of the card)
|
| 106 |
|
|
|
| 107 |
|
|
WDIOC_GETSTATUS
|
| 108 |
|
|
This returns the status of the card, with the bits of
|
| 109 |
|
|
WDIOF_* bitwise-anded into the value. (The comments
|
| 110 |
|
|
are in linux/pcwd.h)
|
| 111 |
|
|
|
| 112 |
|
|
WDIOC_GETBOOTSTATUS
|
| 113 |
|
|
This returns the status of the card that was reported
|
| 114 |
|
|
at bootup.
|
| 115 |
|
|
|
| 116 |
|
|
WDIOC_GETTEMP
|
| 117 |
|
|
This returns the temperature of the card. (You can also
|
| 118 |
|
|
read /dev/watchdog, which gives a temperature update
|
| 119 |
|
|
every second.)
|
| 120 |
|
|
|
| 121 |
|
|
WDIOC_SETOPTIONS
|
| 122 |
|
|
This lets you set the options of the card. You can either
|
| 123 |
|
|
enable or disable the card this way.
|
| 124 |
|
|
|
| 125 |
|
|
WDIOC_KEEPALIVE
|
| 126 |
|
|
This pings the card to tell it not to reset your computer.
|
| 127 |
|
|
|
| 128 |
|
|
And that's all she wrote!
|
| 129 |
|
|
|
| 130 |
|
|
-- Ken Hollis
|
| 131 |
|
|
(kenji@bitgate.com)
|
| 132 |
|
|
|
| 133 |
|
|
(This documentation may be out of date. Check
|
| 134 |
|
|
http://ftp.bitgate.com/pcwd/ for the absolute latest additions.)
|
