xref: /OK3568_Linux_fs/kernel/Documentation/devicetree/bindings/timer/arm,twd.txt (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun* ARM Timer Watchdog
2*4882a593Smuzhiyun
3*4882a593SmuzhiyunARM 11MP, Cortex-A5 and Cortex-A9 are often associated with a per-core
4*4882a593SmuzhiyunTimer-Watchdog (aka TWD), which provides both a per-cpu local timer
5*4882a593Smuzhiyunand watchdog.
6*4882a593Smuzhiyun
7*4882a593SmuzhiyunThe TWD is usually attached to a GIC to deliver its two per-processor
8*4882a593Smuzhiyuninterrupts.
9*4882a593Smuzhiyun
10*4882a593Smuzhiyun** Timer node required properties:
11*4882a593Smuzhiyun
12*4882a593Smuzhiyun- compatible : Should be one of:
13*4882a593Smuzhiyun	"arm,cortex-a9-twd-timer"
14*4882a593Smuzhiyun	"arm,cortex-a5-twd-timer"
15*4882a593Smuzhiyun	"arm,arm11mp-twd-timer"
16*4882a593Smuzhiyun
17*4882a593Smuzhiyun- interrupts : One interrupt to each core
18*4882a593Smuzhiyun
19*4882a593Smuzhiyun- reg : Specify the base address and the size of the TWD timer
20*4882a593Smuzhiyun	register window.
21*4882a593Smuzhiyun
22*4882a593SmuzhiyunOptional
23*4882a593Smuzhiyun
24*4882a593Smuzhiyun- always-on : a boolean property. If present, the timer is powered through
25*4882a593Smuzhiyun  an always-on power domain, therefore it never loses context.
26*4882a593Smuzhiyun
27*4882a593SmuzhiyunExample:
28*4882a593Smuzhiyun
29*4882a593Smuzhiyun	twd-timer@2c000600 {
30*4882a593Smuzhiyun		compatible = "arm,arm11mp-twd-timer"";
31*4882a593Smuzhiyun		reg = <0x2c000600 0x20>;
32*4882a593Smuzhiyun		interrupts = <1 13 0xf01>;
33*4882a593Smuzhiyun	};
34*4882a593Smuzhiyun
35*4882a593Smuzhiyun** Watchdog node properties:
36*4882a593Smuzhiyun
37*4882a593Smuzhiyun- compatible : Should be one of:
38*4882a593Smuzhiyun	"arm,cortex-a9-twd-wdt"
39*4882a593Smuzhiyun	"arm,cortex-a5-twd-wdt"
40*4882a593Smuzhiyun	"arm,arm11mp-twd-wdt"
41*4882a593Smuzhiyun
42*4882a593Smuzhiyun- interrupts : One interrupt to each core
43*4882a593Smuzhiyun
44*4882a593Smuzhiyun- reg : Specify the base address and the size of the TWD watchdog
45*4882a593Smuzhiyun	register window.
46*4882a593Smuzhiyun
47*4882a593SmuzhiyunExample:
48*4882a593Smuzhiyun
49*4882a593Smuzhiyun	twd-watchdog@2c000620 {
50*4882a593Smuzhiyun		compatible = "arm,arm11mp-twd-wdt";
51*4882a593Smuzhiyun		reg = <0x2c000620 0x20>;
52*4882a593Smuzhiyun		interrupts = <1 14 0xf01>;
53*4882a593Smuzhiyun	};
54