[PATCH v4 06/10] dt-bindings: cpufreq: Add binding for NVIDIA Tegra20/30

From: Dmitry Osipenko <digetx@gmail.com>
To: Thierry Reding <thierry.reding@gmail.com>,
	Jonathan Hunter <jonathanh@nvidia.com>,
	Peter De Schrijver <pdeschrijver@nvidia.com>,
	Prashant Gaikwad <pgaikwad@nvidia.com>,
	"Rafael J. Wysocki" <rjw@rjwysocki.net>,
	Viresh Kumar <viresh.kumar@linaro.org>,
	Michael Turquette <mturquette@baylibre.com>,
	Stephen Boyd <sboyd@kernel.org>, Peter Geis <pgwipeout@gmail.com>,
	Nicolas Chauvet <kwizart@gmail.com>,
	Marcel Ziswiler <marcel.ziswiler@toradex.com>
Cc: linux-pm@vger.kernel.org, linux-tegra@vger.kernel.org,
	linux-clk@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH v4 06/10] dt-bindings: cpufreq: Add binding for NVIDIA Tegra20/30
Date: Mon, 11 Nov 2019 23:54:15 +0300	[thread overview]
Message-ID: <20191111205419.16768-7-digetx@gmail.com> (raw)
In-Reply-To: <20191111205419.16768-1-digetx@gmail.com>

Add device-tree binding that describes CPU frequency-scaling hardware
found on NVIDIA Tegra20/30 SoCs.

Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
---
 .../cpufreq/nvidia,tegra20-cpufreq.txt        | 56 +++++++++++++++++++
 1 file changed, 56 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/cpufreq/nvidia,tegra20-cpufreq.txt

diff --git a/Documentation/devicetree/bindings/cpufreq/nvidia,tegra20-cpufreq.txt b/Documentation/devicetree/bindings/cpufreq/nvidia,tegra20-cpufreq.txt
new file mode 100644
index 000000000000..daeca6ae6b76
--- /dev/null
+++ b/Documentation/devicetree/bindings/cpufreq/nvidia,tegra20-cpufreq.txt
@@ -0,0 +1,56 @@
+Binding for NVIDIA Tegra20 CPUFreq
+==================================
+
+Required properties:
+- clocks: Must contain an entry for the CPU clock.
+  See ../clocks/clock-bindings.txt for details.
+- operating-points-v2: See ../bindings/opp/opp.txt for details.
+- #cooling-cells: Should be 2. See ../thermal/thermal.txt for details.
+
+For each opp entry in 'operating-points-v2' table:
+- opp-supported-hw: Two bitfields indicating:
+	On Tegra20:
+	1. CPU process ID mask
+	2. SoC speedo ID mask
+
+	On Tegra30:
+	1. CPU process ID mask
+	2. CPU speedo ID mask
+
+	A bitwise AND is performed against these values and if any bit
+	matches, the OPP gets enabled.
+
+- opp-microvolt: CPU voltage triplet.
+
+Optional properties:
+- cpu-supply: Phandle to the CPU power supply.
+
+Example:
+	regulators {
+		cpu_reg: regulator0 {
+			regulator-name = "vdd_cpu";
+		};
+	};
+
+	cpu0_opp_table: opp_table0 {
+		compatible = "operating-points-v2";
+
+		opp@456000000 {
+			clock-latency-ns = <125000>;
+			opp-microvolt = <825000 825000 1125000>;
+			opp-supported-hw = <0x03 0x0001>;
+			opp-hz = /bits/ 64 <456000000>;
+		};
+
+		...
+	};
+
+	cpus {
+		cpu@0 {
+			compatible = "arm,cortex-a9";
+			clocks = <&tegra_car TEGRA20_CLK_CCLK>;
+			operating-points-v2 = <&cpu0_opp_table>;
+			cpu-supply = <&cpu_reg>;
+			#cooling-cells = <2>;
+		};
+	};
-- 
2.23.0
