Re: [PATCH v10 1/2] dt-bindings: cpufreq: Introduce QCOM CPUFREQ Firmware bindings

From: Taniya Das
Date: Sat Dec 01 2018 - 22:45:05 EST


Hello Matthias,

On 11/21/2018 11:32 PM, Matthias Kaehlcke wrote:
On Wed, Nov 21, 2018 at 04:12:46PM +0530, Taniya Das wrote:
Add QCOM cpufreq firmware device bindings for Qualcomm Technology Inc's
SoCs. This is required for managing the cpu frequency transitions which are
controlled by the hardware engine.

Signed-off-by: Taniya Das <tdas@xxxxxxxxxxxxxx>
---
.../bindings/cpufreq/cpufreq-qcom-hw.txt | 172 +++++++++++++++++++++
1 file changed, 172 insertions(+)
create mode 100644 Documentation/devicetree/bindings/cpufreq/cpufreq-qcom-hw.txt

diff --git a/Documentation/devicetree/bindings/cpufreq/cpufreq-qcom-hw.txt b/Documentation/devicetree/bindings/cpufreq/cpufreq-qcom-hw.txt
new file mode 100644
index 0000000..90e396b
--- /dev/null
+++ b/Documentation/devicetree/bindings/cpufreq/cpufreq-qcom-hw.txt
@@ -0,0 +1,172 @@
+Qualcomm Technologies, Inc. CPUFREQ Bindings
+
+CPUFREQ HW is a hardware engine used by some Qualcomm Technologies, Inc. (QTI)
+SoCs to manage frequency in hardware. It is capable of controlling frequency
+for multiple clusters.
+
+Properties:
+- compatible
+ Usage: required
+ Value type: <string>
+ Definition: must be "qcom,cpufreq-hw".
+
+- clocks
+ Usage: required
+ Value type: <phandle> From common clock binding.
+ Definition: clock handle for XO clock and GPLL0 clock.
+
+- clock-names
+ Usage: required
+ Value type: <string> From common clock binding.
+ Definition: must be "xo", "cpu_clk".
+
+- reg
+ Usage: required
+ Value type: <prop-encoded-array>
+ Definition: Addresses and sizes for the memory of the HW bases in
+ each frequency domain.
+- reg-names
+ Usage: Optional
+ Value type: <string>
+ Definition: Frequency domain name i.e.
+ "freq-domain0", "freq-domain1".
+
+- freq-domain-cells:
+ Usage: required.
+ Definition: Number of cells in a freqency domain specifier.
+
+* Property qcom,freq-domain
+Devices supporting freq-domain must set their "qcom,freq-domain" property with
+phandle to a cpufreq_hw followed by the Domain ID(0/1) in the CPU DT node.
+
+
+Example:
+
+Example 1: Dual-cluster, Quad-core per cluster. CPUs within a cluster switch
+DCVS state together.
+
+/ {
+ cpus {
+ #address-cells = <2>;
+ #size-cells = <0>;
+
+ CPU0: cpu@0 {
+ device_type = "cpu";
+ compatible = "qcom,kryo385";
+ reg = <0x0 0x0>;
+ enable-method = "psci";
+ next-level-cache = <&L2_0>;
+ qcom,freq-domain = <&cpufreq_hw 0>;
+ L2_0: l2-cache {
+ compatible = "cache";
+ next-level-cache = <&L3_0>;
+ L3_0: l3-cache {
+ compatible = "cache";
+ };
+ };
+ };
+
+ CPU1: cpu@100 {
+ device_type = "cpu";
+ compatible = "qcom,kryo385";
+ reg = <0x0 0x100>;
+ enable-method = "psci";
+ next-level-cache = <&L2_100>;
+ qcom,freq-domain = <&cpufreq_hw 0>;
+ L2_100: l2-cache {
+ compatible = "cache";
+ next-level-cache = <&L3_0>;
+ };
+ };
+
+ CPU2: cpu@200 {
+ device_type = "cpu";
+ compatible = "qcom,kryo385";
+ reg = <0x0 0x200>;
+ enable-method = "psci";
+ next-level-cache = <&L2_200>;
+ qcom,freq-domain = <&cpufreq_hw 0>;
+ L2_200: l2-cache {
+ compatible = "cache";
+ next-level-cache = <&L3_0>;
+ };
+ };
+
+ CPU3: cpu@300 {
+ device_type = "cpu";
+ compatible = "qcom,kryo385";
+ reg = <0x0 0x300>;
+ enable-method = "psci";
+ next-level-cache = <&L2_300>;
+ qcom,freq-domain = <&cpufreq_hw 0>;
+ L2_300: l2-cache {
+ compatible = "cache";
+ next-level-cache = <&L3_0>;
+ };
+ };
+
+ CPU4: cpu@400 {
+ device_type = "cpu";
+ compatible = "qcom,kryo385";
+ reg = <0x0 0x400>;
+ enable-method = "psci";
+ next-level-cache = <&L2_400>;
+ qcom,freq-domain = <&cpufreq_hw 1>;
+ L2_400: l2-cache {
+ compatible = "cache";
+ next-level-cache = <&L3_0>;
+ };
+ };
+
+ CPU5: cpu@500 {
+ device_type = "cpu";
+ compatible = "qcom,kryo385";
+ reg = <0x0 0x500>;
+ enable-method = "psci";
+ next-level-cache = <&L2_500>;
+ qcom,freq-domain = <&cpufreq_hw 1>;
+ L2_500: l2-cache {
+ compatible = "cache";
+ next-level-cache = <&L3_0>;
+ };
+ };
+
+ CPU6: cpu@600 {
+ device_type = "cpu";
+ compatible = "qcom,kryo385";
+ reg = <0x0 0x600>;
+ enable-method = "psci";
+ next-level-cache = <&L2_600>;
+ qcom,freq-domain = <&cpufreq_hw 1>;
+ L2_600: l2-cache {
+ compatible = "cache";
+ next-level-cache = <&L3_0>;
+ };
+ };
+
+ CPU7: cpu@700 {
+ device_type = "cpu";
+ compatible = "qcom,kryo385";
+ reg = <0x0 0x700>;
+ enable-method = "psci";
+ next-level-cache = <&L2_700>;
+ qcom,freq-domain = <&cpufreq_hw 1>;
+ L2_700: l2-cache {
+ compatible = "cache";
+ next-level-cache = <&L3_0>;
+ };
+ };
+ };
+
+ soc {
+ cpufreq_hw: cpufreq@17d43000 {
+ compatible = "qcom,cpufreq-hw";
+ reg = <0x17d43000 0x1400>, <0x17d45800 0x1400>;
+ reg-names = "freq-domain0", "freq-domain1";
+
+ clocks = <&rpmhcc RPMH_CXO_CLK>, <&gcc GPLL0>;
+ clock-names = "xo", "gcc_cpuss_gpll0_clk_src";

I don't have/find the document with the clock configuration of this
IP block, but the 'clock-names' sound more like aliases for the actual
clocks specified in the 'clocks' property (especially
'gcc_cpuss_gpll0_clk_src') than input signals from the IP POV, which
I'd expect to have more generic names.


Updated the clock name to "alternate" in the latest series.

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