1 What: /sys/class/watchdog/watchdogn/ 1 What: /sys/class/watchdog/watchdogn/bootstatus
2 Date: August 2015 2 Date: August 2015
3 Contact: Wim Van Sebroeck <wim@iguana.be 3 Contact: Wim Van Sebroeck <wim@iguana.be>
4 Description: 4 Description:
5 It is a read only file. It con 5 It is a read only file. It contains status of the watchdog
6 device at boot. It is equivale 6 device at boot. It is equivalent to WDIOC_GETBOOTSTATUS of
7 ioctl interface. 7 ioctl interface.
8 8
9 What: /sys/class/watchdog/watchdogn/ 9 What: /sys/class/watchdog/watchdogn/options
10 Date: April 2023 10 Date: April 2023
11 Contact: Thomas Weißschuh 11 Contact: Thomas Weißschuh
12 Description: 12 Description:
13 It is a read only file. It con 13 It is a read only file. It contains options of watchdog device.
14 14
15 What: /sys/class/watchdog/watchdogn/ 15 What: /sys/class/watchdog/watchdogn/fw_version
16 Date: April 2023 16 Date: April 2023
17 Contact: Thomas Weißschuh 17 Contact: Thomas Weißschuh
18 Description: 18 Description:
19 It is a read only file. It con 19 It is a read only file. It contains firmware version of
20 watchdog device. 20 watchdog device.
21 21
22 What: /sys/class/watchdog/watchdogn/ 22 What: /sys/class/watchdog/watchdogn/identity
23 Date: August 2015 23 Date: August 2015
24 Contact: Wim Van Sebroeck <wim@iguana.be 24 Contact: Wim Van Sebroeck <wim@iguana.be>
25 Description: 25 Description:
26 It is a read only file. It con 26 It is a read only file. It contains identity string of
27 watchdog device. 27 watchdog device.
28 28
29 What: /sys/class/watchdog/watchdogn/ 29 What: /sys/class/watchdog/watchdogn/nowayout
30 Date: August 2015 30 Date: August 2015
31 Contact: Wim Van Sebroeck <wim@iguana.be 31 Contact: Wim Van Sebroeck <wim@iguana.be>
32 Description: 32 Description:
33 It is a read/write file. While 33 It is a read/write file. While reading, it gives '1'
34 if the device has the nowayout 34 if the device has the nowayout feature set, otherwise
35 it gives '0'. Writing a '1' to 35 it gives '0'. Writing a '1' to the file enables the
36 nowayout feature. Once set, th 36 nowayout feature. Once set, the nowayout feature
37 cannot be disabled, so writing 37 cannot be disabled, so writing a '0' either has no
38 effect (if the feature was alr 38 effect (if the feature was already disabled) or
39 results in a permission error. 39 results in a permission error.
40 40
41 What: /sys/class/watchdog/watchdogn/ 41 What: /sys/class/watchdog/watchdogn/state
42 Date: August 2015 42 Date: August 2015
43 Contact: Wim Van Sebroeck <wim@iguana.be 43 Contact: Wim Van Sebroeck <wim@iguana.be>
44 Description: 44 Description:
45 It is a read only file. It giv 45 It is a read only file. It gives active/inactive status of
46 watchdog device. 46 watchdog device.
47 47
48 What: /sys/class/watchdog/watchdogn/ 48 What: /sys/class/watchdog/watchdogn/status
49 Date: August 2015 49 Date: August 2015
50 Contact: Wim Van Sebroeck <wim@iguana.be 50 Contact: Wim Van Sebroeck <wim@iguana.be>
51 Description: 51 Description:
52 It is a read only file. It con 52 It is a read only file. It contains watchdog device's
53 internal status bits. It is eq 53 internal status bits. It is equivalent to WDIOC_GETSTATUS
54 of ioctl interface. 54 of ioctl interface.
55 55
56 What: /sys/class/watchdog/watchdogn/ 56 What: /sys/class/watchdog/watchdogn/timeleft
57 Date: August 2015 57 Date: August 2015
58 Contact: Wim Van Sebroeck <wim@iguana.be 58 Contact: Wim Van Sebroeck <wim@iguana.be>
59 Description: 59 Description:
60 It is a read only file. It con 60 It is a read only file. It contains value of time left for
61 reset generation. It is equiva 61 reset generation. It is equivalent to WDIOC_GETTIMELEFT of
62 ioctl interface. 62 ioctl interface.
63 63
64 What: /sys/class/watchdog/watchdogn/ 64 What: /sys/class/watchdog/watchdogn/timeout
65 Date: August 2015 65 Date: August 2015
66 Contact: Wim Van Sebroeck <wim@iguana.be 66 Contact: Wim Van Sebroeck <wim@iguana.be>
67 Description: 67 Description:
68 It is a read only file. It is 68 It is a read only file. It is read to know about current
69 value of timeout programmed. 69 value of timeout programmed.
70 70
71 What: /sys/class/watchdog/watchdogn/ 71 What: /sys/class/watchdog/watchdogn/pretimeout
72 Date: December 2016 72 Date: December 2016
73 Contact: Wim Van Sebroeck <wim@iguana.be 73 Contact: Wim Van Sebroeck <wim@iguana.be>
74 Description: 74 Description:
75 It is a read only file. It spe 75 It is a read only file. It specifies the time in seconds before
76 timeout when the pretimeout in 76 timeout when the pretimeout interrupt is delivered. Pretimeout
77 is an optional feature. 77 is an optional feature.
78 78
79 What: /sys/class/watchdog/watchdogn/ 79 What: /sys/class/watchdog/watchdogn/pretimeout_avaialable_governors
80 Date: February 2017 80 Date: February 2017
81 Contact: Wim Van Sebroeck <wim@iguana.be 81 Contact: Wim Van Sebroeck <wim@iguana.be>
82 Description: 82 Description:
83 It is a read only file. It sho 83 It is a read only file. It shows the pretimeout governors
84 available for this watchdog. 84 available for this watchdog.
85 85
86 What: /sys/class/watchdog/watchdogn/ 86 What: /sys/class/watchdog/watchdogn/pretimeout_governor
87 Date: February 2017 87 Date: February 2017
88 Contact: Wim Van Sebroeck <wim@iguana.be 88 Contact: Wim Van Sebroeck <wim@iguana.be>
89 Description: 89 Description:
90 It is a read/write file. When 90 It is a read/write file. When read, the currently assigned
91 pretimeout governor is returne 91 pretimeout governor is returned. When written, it sets
92 the pretimeout governor. 92 the pretimeout governor.
93 93
94 What: /sys/class/watchdog/watchdog1/ 94 What: /sys/class/watchdog/watchdog1/access_cs0
95 Date: August 2019 95 Date: August 2019
96 Contact: Ivan Mikhaylov <i.mikhaylov@yad 96 Contact: Ivan Mikhaylov <i.mikhaylov@yadro.com>,
97 Alexander Amelkin <a.amelkin@ya 97 Alexander Amelkin <a.amelkin@yadro.com>
98 Description: 98 Description:
99 It is a read/write file. This 99 It is a read/write file. This attribute exists only if the
100 system has booted from the alt 100 system has booted from the alternate flash chip due to
101 expiration of a watchdog timer 101 expiration of a watchdog timer of AST2400/AST2500 when
102 alternate boot function was en 102 alternate boot function was enabled with 'aspeed,alt-boot'
103 devicetree option for that wat 103 devicetree option for that watchdog or with an appropriate
104 h/w strapping (for WDT2 only). 104 h/w strapping (for WDT2 only).
105 105
106 At alternate flash the 'access 106 At alternate flash the 'access_cs0' sysfs node provides:
107 107
108 ast2400: 108 ast2400:
109 a way to get a 109 a way to get access to the primary SPI flash
110 chip at CS0 af 110 chip at CS0 after booting from the alternate
111 chip at CS1. 111 chip at CS1.
112 ast2500: 112 ast2500:
113 a way to resto 113 a way to restore the normal address mapping
114 from (CS0->CS1 114 from (CS0->CS1, CS1->CS0) to (CS0->CS0,
115 CS1->CS1). 115 CS1->CS1).
116 116
117 Clearing the boot code selecti 117 Clearing the boot code selection and timeout counter also
118 resets to the initial state th 118 resets to the initial state the chip select line mapping. When
119 the SoC is in normal mapping s 119 the SoC is in normal mapping state (i.e. booted from CS0),
120 clearing those bits does nothi 120 clearing those bits does nothing for both versions of the SoC.
121 For alternate boot mode (boote 121 For alternate boot mode (booted from CS1 due to wdt2
122 expiration) the behavior diffe 122 expiration) the behavior differs as described above.
123 123
124 This option can be used with w 124 This option can be used with wdt2 (watchdog1) only.
125 125
126 When read, the current status 126 When read, the current status of the boot code selection is
127 shown. When written with any n 127 shown. When written with any non-zero value, it clears
128 the boot code selection and th 128 the boot code selection and the timeout counter, which results
129 in chipselect reset for AST240 129 in chipselect reset for AST2400/AST2500.
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.