dt-bindings: watchdog: add mpc8xxx-wdt support

Add description of DT bindings for mpc8xxx-wdt driver which
handles the CPU watchdog timer on the mpc83xx, mpc86xx and mpc8xx.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>

diff --git a/Documentation/devicetree/bindings/watchdog/mpc8xxx-wdt.txt b/Documentation/devicetree/bindings/watchdog/mpc8xxx-wdt.txt
new file mode 100644 (file)
index 0000000..a384ff5
--- /dev/null
+++ b/Documentation/devicetree/bindings/watchdog/mpc8xxx-wdt.txt
@@ -0,0 +1,25 @@
+* Freescale mpc8xxx watchdog driver (For 83xx, 86xx and 8xx)
+
+Required properties:
+- compatible: Shall contain one of the following:
+       "mpc83xx_wdt" for an mpc83xx
+       "fsl,mpc8610-wdt" for an mpc86xx
+       "fsl,mpc823-wdt" for an mpc8xx
+- reg: base physical address and length of the area hosting the
+       watchdog registers.
+               On the 83xx, "Watchdog Timer Registers" area:   <0x200 0x100>
+               On the 86xx, "Watchdog Timer Registers" area:   <0xe4000 0x100>
+               On the 8xx, "General System Interface Unit" area: <0x0 0x10>
+
+Optional properties:
+- reg: additional physical address and length (4) of location of the
+       Reset Status Register (called RSTRSCR on the mpc86xx)
+               On the 83xx, it is located at offset 0x910
+               On the 86xx, it is located at offset 0xe0094
+               On the 8xx, it is located at offset 0x288
+
+Example:
+               WDT: watchdog@0 {
+                   compatible = "fsl,mpc823-wdt";
+                   reg = <0x0 0x10 0x288 0x4>;
+               };