powerpc/4xx: Add optional "reset_type" property to control reboot via dts

By setting "reset_type" to one of the following values, the default
software reset mechanism may be overidden. Here the possible values of
"reset_type":

  1 - PPC4xx core reset
  2 - PPC4xx chip reset
  3 - PPC4xx system reset (default)

This will be used by a new PPC440SPe board port, which needs a "chip
reset" instead of the default "system reset" to be asserted.

Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>

1 files changed, 18 insertions, 0 deletions

diff --git a/Documentation/powerpc/dts-bindings/4xx/reboot.txt b/Documentation/powerpc/dts-bindings/4xx/reboot.txt
new file mode 100644
index 000000000000..d7217260589c
--- /dev/null
+++ b/Documentation/powerpc/dts-bindings/4xx/reboot.txt
@@ -0,0 +1,18 @@
+Reboot property to control system reboot on PPC4xx systems:
+
+By setting "reset_type" to one of the following values, the default
+software reset mechanism may be overidden. Here the possible values of
+"reset_type":
+
+      1 - PPC4xx core reset
+      2 - PPC4xx chip reset
+      3 - PPC4xx system reset (default)
+
+Example:
+
+                cpu@0 {
+                        device_type = "cpu";
+                        model = "PowerPC,440SPe";
+                        ...
+                        reset-type = <2>;       /* Use chip-reset */
+                };