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Diffstat (limited to 'Documentation/devicetree/bindings/cpufreq/brcm,stb-avs-cpu-freq.txt')
-rw-r--r-- | Documentation/devicetree/bindings/cpufreq/brcm,stb-avs-cpu-freq.txt | 76 |
1 files changed, 76 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/cpufreq/brcm,stb-avs-cpu-freq.txt b/Documentation/devicetree/bindings/cpufreq/brcm,stb-avs-cpu-freq.txt new file mode 100644 index 000000000..73470ecd1 --- /dev/null +++ b/Documentation/devicetree/bindings/cpufreq/brcm,stb-avs-cpu-freq.txt @@ -0,0 +1,76 @@ +Broadcom AVS mail box and interrupt register bindings +===================================================== + +A total of three DT nodes are required. One node (brcm,avs-cpu-data-mem) +references the mailbox register used to communicate with the AVS CPU[1]. 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 a driver. Interrupting the AVS CPU is mandatory for +commands to be processed. + +The interface also requires a reference to the AVS host interrupt controller, +so a driver can react to interrupts generated by the AVS CPU whenever a command +has been processed. See [2] for more information on the brcm,l2-intc node. + +[1] The AVS CPU is an independent co-processor that runs proprietary +firmware. On some SoCs, this firmware supports DFS and DVFS in addition to +Adaptive Voltage Scaling. + +[2] Documentation/devicetree/bindings/interrupt-controller/brcm,l2-intc.txt + + +Node brcm,avs-cpu-data-mem +-------------------------- + +Required properties: +- compatible: must include: brcm,avs-cpu-data-mem and + should include: one of 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-names: The name of the interrupt used to interrupt the host. + +Optional properties: +- None + +Node brcm,avs-cpu-l2-intr +------------------------- + +Required properties: +- compatible: must include: brcm,avs-cpu-l2-intr and + should include: one of 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>; + }; |