[PATCH 1/3] dt: cpufreq: brcm: New binding document for brcm-avs-cpufreq

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Add the binding document for the new brcm-avs-cpufreq driver.

Signed-off-by: Markus Mayer <mmayer@xxxxxxxxxxxx>
---
 .../bindings/cpufreq/brcm-avs-cpufreq.txt          | 84 ++++++++++++++++++++++
 MAINTAINERS                                        |  7 ++
 2 files changed, 91 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/cpufreq/brcm-avs-cpufreq.txt

diff --git a/Documentation/devicetree/bindings/cpufreq/brcm-avs-cpufreq.txt b/Documentation/devicetree/bindings/cpufreq/brcm-avs-cpufreq.txt
new file mode 100644
index 0000000..707ebe5
--- /dev/null
+++ b/Documentation/devicetree/bindings/cpufreq/brcm-avs-cpufreq.txt
@@ -0,0 +1,84 @@
+Broadcom AVS CPUfreq driver
+===========================
+
+This driver provides voltage and frequency scaling on Broadcom SoCs using
+the AVS firmware with DVFS support. The AVS firmware is running on its own
+co-processor. The driver supports both uniprocessor (UP) and symmetric
+multiprocessor (SMP) systems which share clock and voltage across all CPUs.
+
+Actual voltage and frequency scaling is done solely by the AVS firmware.
+This driver does not change frequency or voltage itself. It provides a
+standard CPUfreq interface to the rest of the kernel and to userland. It
+interfaces with the AVS firmware to effect the requested changes and to
+report back the current system status in a way that is expected by existing
+tools.
+
+This driver requires two DT nodes. One node (brcm,avs-cpu-data-mem)
+references the mailbox register used to communicate with the AVS CPU. The
+second node (brcm,avs-cpu-l2-intr) is required to trigger an interrupt on
+the AVS CPU. The interrupt tells the AVS CPU that it needs to process a
+command sent to it by this driver. Interrupting the AVS CPU is mandatory for
+commands to be processed.
+
+It also requires a reference to the AVS host interrrupt controller, so the
+driver can react to interrupts generated by the AVS CPU whenever a command
+has been processed. See [1] for more information on the brcm,l2-intc.
+
+[1] Documentation/devicetree/bindings/interrupt-controller/brcm,l2-intc.txt
+
+
+Node brcm,avs-cpu-data-mem
+--------------------------
+
+Required properties:
+- compatible: Sould be one of: brcm,avs-cpu-data-mem,
+              brcm,bcm7271-avs-cpu-data-mem or brcm,bcm7268-avs-cpu-data-mem
+- reg: Specifies base physical address and size of the registers.
+- interrupts: The interrupt that the AVS CPU will use to interrupt the host
+              when a command completed.
+- interrupt-parent: The interrupt controller the above interrupt is routed
+                    through.
+- interrupt-names: The name of the interrupt used to interrupt the host.
+
+Optional properties:
+- None
+
+Node brcm,avs-cpu-l2-intr
+-------------------------
+
+Required properties:
+- compatible: Sould be one of: brcm,avs-cpu-l2-intr,
+              brcm,bcm7271-avs-cpu-l2-intr or brcm,bcm7268-avs-cpu-l2-intr
+- reg: Specifies base physical address and size of the registers.
+
+Optional properties:
+- None
+
+
+Example
+=======
+
+	avs_host_l2_intc: interrupt-controller@f04d1200 {                
+		#interrupt-cells = <1>;                                  
+		compatible = "brcm,l2-intc";                             
+		interrupt-parent = <&intc>;                              
+		reg = <0xf04d1200 0x48>;                                 
+		interrupt-controller;                                    
+		interrupts = <0x0 0x19 0x0>;                             
+		interrupt-names = "avs";                                 
+	};                                                               
+
+	avs-cpu-data-mem@f04c4000 {
+		compatible = "brcm,bcm7271-avs-cpu-data-mem",
+				"brcm,avs-cpu-data-mem";
+		reg = <0xf04c4000 0x60>;
+		interrupts = <0x1a>;
+		interrupt-parent = <&avs_host_l2_intc>;
+		interrupt-names = "sw_intr";
+	};
+
+	avs-cpu-l2-intr@f04d1100 {
+		compatible = "brcm,bcm7271-avs-cpu-l2-intr",
+				"brcm,avs-cpu-l2-intr";
+		reg = <0xf04d1100 0x10>;
+	};
diff --git a/MAINTAINERS b/MAINTAINERS
index 20bb1d0..228a5a8 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2689,6 +2689,13 @@ L:	bcm-kernel-feedback-list@xxxxxxxxxxxx
 S:	Maintained
 F:	drivers/mtd/nand/brcmnand/
 
+BROADCOM STB CPUFREQ DRIVER
+M:	Markus Mayer <mmayer@xxxxxxxxxxxx>
+M:	bcm-kernel-feedback-list@xxxxxxxxxxxx
+L:	linux-pm@xxxxxxxxxxxxxxx
+S:	Maintained
+F:	Documentation/devicetree/bindings/cpufreq/brcm-avs-cpufreq.txt
+
 BROADCOM SPECIFIC AMBA DRIVER (BCMA)
 M:	Rafał Miłecki <zajec5@xxxxxxxxx>
 L:	linux-wireless@xxxxxxxxxxxxxxx
-- 
2.7.4

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