Blame view

kernel/linux-imx6_3.14.28/Documentation/watchdog/pcwd-watchdog.txt 2.21 KB
6b13f685e   김민수   BSP 최초 추가
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
  Last reviewed: 10/05/2007
  
                       Berkshire Products PC Watchdog Card
                     Support for ISA Cards  Revision A and C
             Documentation and Driver by Ken Hollis <kenji@bitgate.com>
  
   The PC Watchdog is a card that offers the same type of functionality that
   the WDT card does, only it doesn't require an IRQ to run.  Furthermore,
   the Revision C card allows you to monitor any IO Port to automatically
   trigger the card into being reset.  This way you can make the card
   monitor hard drive status, or anything else you need.
  
   The Watchdog Driver has one basic role: to talk to the card and send
   signals to it so it doesn't reset your computer ... at least during
   normal operation.
  
   The Watchdog Driver will automatically find your watchdog card, and will
   attach a running driver for use with that card.  After the watchdog
   drivers have initialized, you can then talk to the card using a PC
   Watchdog program.
  
   I suggest putting a "watchdog -d" before the beginning of an fsck, and
   a "watchdog -e -t 1" immediately after the end of an fsck.  (Remember
   to run the program with an "&" to run it in the background!)
  
   If you want to write a program to be compatible with the PC Watchdog
   driver, simply use of modify the watchdog test program:
   Documentation/watchdog/src/watchdog-test.c
  
  
   Other IOCTL functions include:
  
  	WDIOC_GETSUPPORT
  		This returns the support of the card itself.  This
  		returns in structure "PCWDS" which returns:
  			options = WDIOS_TEMPPANIC
  				  (This card supports temperature)
  			firmware_version = xxxx
  				  (Firmware version of the card)
  
  	WDIOC_GETSTATUS
  		This returns the status of the card, with the bits of
  		WDIOF_* bitwise-anded into the value.  (The comments
  		are in linux/pcwd.h)
  
  	WDIOC_GETBOOTSTATUS
  		This returns the status of the card that was reported
  		at bootup.
  
  	WDIOC_GETTEMP
  		This returns the temperature of the card.  (You can also
  		read /dev/watchdog, which gives a temperature update
  		every second.)
  
  	WDIOC_SETOPTIONS
  		This lets you set the options of the card.  You can either
  		enable or disable the card this way.
  
  	WDIOC_KEEPALIVE
  		This pings the card to tell it not to reset your computer.
  
   And that's all she wrote!
  
   -- Ken Hollis
      (kenji@bitgate.com)