[PATCH 3/6] docs: Document BCM23550 bindings

From: Chris Brand
Date: Thu May 05 2016 - 16:48:27 EST


Add binding document for Broadcom BCM23550 SoC.

BCM23550 has a Cluster Dormant Control IP block that holds cores
in an idle state. Introduce a new CPU enable method in which the CDC is
accessed to bring the core online.

Signed-off-by: Chris Brand <chris.brand@xxxxxxxxxxxx>
---
.../bindings/arm/bcm/brcm,bcm23550-cpu-method.txt | 36 ++++++++++++++++++++++
.../devicetree/bindings/arm/bcm/brcm,bcm23550.txt | 15 +++++++++
Documentation/devicetree/bindings/arm/cpus.txt | 1 +
3 files changed, 52 insertions(+)
create mode 100644 Documentation/devicetree/bindings/arm/bcm/brcm,bcm23550-cpu-method.txt
create mode 100644 Documentation/devicetree/bindings/arm/bcm/brcm,bcm23550.txt

diff --git a/Documentation/devicetree/bindings/arm/bcm/brcm,bcm23550-cpu-method.txt b/Documentation/devicetree/bindings/arm/bcm/brcm,bcm23550-cpu-method.txt
new file mode 100644
index 000000000000..b1b16872bbca
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/bcm/brcm,bcm23550-cpu-method.txt
@@ -0,0 +1,36 @@
+Broadcom Kona Family CPU Enable Method
+--------------------------------------
+This binding defines the enable method used for starting secondary
+CPUs in the following Broadcom SoCs:
+ BCM23550
+
+The enable method is specified by defining the following required
+properties in the "cpu" device tree node:
+ - enable-method = "brcm,bcm23550-cpu-method";
+ - secondary-boot-reg = <...>;
+
+The secondary-boot-reg property is a u32 value that specifies the
+physical address of the register used to request the ROM holding pen
+code release a secondary CPU. The value written to the register is
+formed by encoding the target CPU id into the low bits of the
+physical start address it should jump to.
+
+Example:
+ cpus {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ cpu0: cpu@0 {
+ device_type = "cpu";
+ compatible = "arm,cortex-a9";
+ reg = <0>;
+ };
+
+ cpu1: cpu@1 {
+ device_type = "cpu";
+ compatible = "arm,cortex-a9";
+ reg = <1>;
+ enable-method = "brcm,bcm23550-cpu-method";
+ secondary-boot-reg = <0x3500417c>;
+ };
+ };
diff --git a/Documentation/devicetree/bindings/arm/bcm/brcm,bcm23550.txt b/Documentation/devicetree/bindings/arm/bcm/brcm,bcm23550.txt
new file mode 100644
index 000000000000..080baad923d6
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/bcm/brcm,bcm23550.txt
@@ -0,0 +1,15 @@
+Broadcom BCM23550 device tree bindings
+--------------------------------------
+
+This document describes the device tree bindings for boards with the BCM23550
+SoC.
+
+Required root node property:
+ - compatible: brcm,bcm23550
+
+Example:
+ / {
+ model = "BCM23550 SoC";
+ compatible = "brcm,bcm23550";
+ [...]
+ }
diff --git a/Documentation/devicetree/bindings/arm/cpus.txt b/Documentation/devicetree/bindings/arm/cpus.txt
index ccc62f145306..8d63711139bd 100644
--- a/Documentation/devicetree/bindings/arm/cpus.txt
+++ b/Documentation/devicetree/bindings/arm/cpus.txt
@@ -194,6 +194,7 @@ nodes to be present and contain the properties described below.
"allwinner,sun8i-a23"
"arm,psci"
"arm,realview-smp"
+ "brcm,bcm23550-cpu-method"
"brcm,bcm-nsp-smp"
"brcm,brahma-b15"
"marvell,armada-375-smp"
--
1.9.1