[PATCH] arm64: dts: ti: k3-j721e: Add support for DFS in J721E A72

Neha Malcom Francis n-francis at ti.com
Wed Dec 13 23:56:37 PST 2023


Add 2G, 1.5G, 1G, 750M, 500M and 250M as the supported frequencies for
A72. This enables support for Dynamic Frequency Scaling (DFS).

Signed-off-by: Neha Malcom Francis <n-francis at ti.com>
---
Boot logs:
https://gist.github.com/nehamalcom/e3c3d0446f0467e7fd28706f7ffaeea8

J721E SoC has three different speed grade devices (see [1], 7.5
Operating Performance Points) which as of today are indiscernible in
software, users of a different speed grade device must manually change
the DTS to ensure their maximum speed frequency is supported.

[1] https://www.ti.com/lit/gpn/tda4vm

 arch/arm64/boot/dts/ti/k3-j721e.dtsi | 35 ++++++++++++++++++++++++++++
 1 file changed, 35 insertions(+)

diff --git a/arch/arm64/boot/dts/ti/k3-j721e.dtsi b/arch/arm64/boot/dts/ti/k3-j721e.dtsi
index a200810df54a..fe92879f5812 100644
--- a/arch/arm64/boot/dts/ti/k3-j721e.dtsi
+++ b/arch/arm64/boot/dts/ti/k3-j721e.dtsi
@@ -48,6 +48,9 @@ cpu0: cpu at 0 {
 			d-cache-line-size = <64>;
 			d-cache-sets = <256>;
 			next-level-cache = <&L2_0>;
+			clocks = <&k3_clks 202 2>;
+			clock-names = "cpu";
+			operating-points-v2 = <&cpu0_opp_table>;
 		};
 
 		cpu1: cpu at 1 {
@@ -62,9 +65,41 @@ cpu1: cpu at 1 {
 			d-cache-line-size = <64>;
 			d-cache-sets = <256>;
 			next-level-cache = <&L2_0>;
+			clocks = <&k3_clks 203 0>;
+			clock-names = "cpu";
+			operating-points-v2 = <&cpu0_opp_table>;
 		};
 	};
 
+	cpu0_opp_table: opp-table {
+		compatible = "operating-points-v2";
+
+		opp6-2000000000 {
+			opp-hz = /bits/ 64 <2000000000>;
+		};
+
+		opp5-1500000000 {
+			opp-hz = /bits/ 64 <1500000000>;
+		};
+
+		opp4-1000000000 {
+			opp-hz = /bits/ 64 <1000000000>;
+		};
+
+		opp3-750000000 {
+			opp-hz = /bits/ 64 <750000000>;
+		};
+
+		opp2-500000000 {
+			opp-hz = /bits/ 64 <500000000>;
+		};
+
+		opp1-250000000 {
+			opp-hz = /bits/ 64 <250000000>;
+		};
+
+	};
+
 	L2_0: l2-cache0 {
 		compatible = "cache";
 		cache-level = <2>;
-- 
2.34.1




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