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+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/cpufreq/virtual,android-v-only-cpufreq.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Android-V-Only Virtual CPUFreq
+
+maintainers:
+ - David Dai <davidai@google.com>
+ - Saravana Kannan <saravanak@google.com>
+
+description:
+ Android-V-Only Virtual CPUFreq is a virtualized driver in guest kernels that
+ sends frequency selection of its vCPUs as a hint to the host through MMIO
+ regions. Each vCPU is associated with a frequency domain which can be shared
+ with other vCPUs. Each frequency domain has its own set of registers for
+ frequency controls.
+
+properties:
+ compatible:
+ const: virtual,android-v-only-cpufreq
+
+ reg:
+ maxItems: 1
+ description:
+ Address and size of region containing frequency controls for each of the
+ frequency domains. Regions for each frequency domain is placed
+ contiguously and contain registers for controlling DVFS(Dynamic Frequency
+ and Voltage) characteristics. The size of the region is proportional to
+ total number of frequency domains. This device also needs the CPUs to
+ list their OPPs using operating-points-v2 tables. The OPP tables for the
+ CPUs should use normalized "frequency" values where the OPP with the
+ highest performance among all the vCPUs is listed as 1024 KHz. The rest
+ of the frequencies of all the vCPUs should be normalized based on their
+ performance relative to that 1024 KHz OPP. This makes it much easier to
+ migrate the VM across systems which might have different physical CPU
+ OPPs.
+
+required:
+ - compatible
+ - reg
+
+additionalProperties: false
+
+examples:
+ - |
+ // This example shows a two CPU configuration with a frequency domain
+ // for each CPU showing normalized performance points.
+ cpus {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ cpu@0 {
+ compatible = "arm,armv8";
+ device_type = "cpu";
+ reg = <0x0>;
+ operating-points-v2 = <&opp_table0>;
+ };
+
+ cpu@1 {
+ compatible = "arm,armv8";
+ device_type = "cpu";
+ reg = <0x0>;
+ operating-points-v2 = <&opp_table1>;
+ };
+ };
+
+ opp_table0: opp-table-0 {
+ compatible = "operating-points-v2";
+
+ opp64000 { opp-hz = /bits/ 64 <64000>; };
+ opp128000 { opp-hz = /bits/ 64 <128000>; };
+ opp192000 { opp-hz = /bits/ 64 <192000>; };
+ opp256000 { opp-hz = /bits/ 64 <256000>; };
+ opp320000 { opp-hz = /bits/ 64 <320000>; };
+ opp384000 { opp-hz = /bits/ 64 <384000>; };
+ opp425000 { opp-hz = /bits/ 64 <425000>; };
+ };
+
+ opp_table1: opp-table-1 {
+ compatible = "operating-points-v2";
+
+ opp64000 { opp-hz = /bits/ 64 <64000>; };
+ opp128000 { opp-hz = /bits/ 64 <128000>; };
+ opp192000 { opp-hz = /bits/ 64 <192000>; };
+ opp256000 { opp-hz = /bits/ 64 <256000>; };
+ opp320000 { opp-hz = /bits/ 64 <320000>; };
+ opp384000 { opp-hz = /bits/ 64 <384000>; };
+ opp448000 { opp-hz = /bits/ 64 <448000>; };
+ opp512000 { opp-hz = /bits/ 64 <512000>; };
+ opp576000 { opp-hz = /bits/ 64 <576000>; };
+ opp640000 { opp-hz = /bits/ 64 <640000>; };
+ opp704000 { opp-hz = /bits/ 64 <704000>; };
+ opp768000 { opp-hz = /bits/ 64 <768000>; };
+ opp832000 { opp-hz = /bits/ 64 <832000>; };
+ opp896000 { opp-hz = /bits/ 64 <896000>; };
+ opp960000 { opp-hz = /bits/ 64 <960000>; };
+ opp1024000 { opp-hz = /bits/ 64 <1024000>; };
+
+ };
+
+ soc {
+ #address-cells = <1>;
+ #size-cells = <1>;
+
+ cpufreq@1040000 {
+ compatible = "virtual,android-v-only-cpufreq";
+ reg = <0x1040000 0x10>;
+ };
+ };