[PATCH AUTOSEL 5.4 07/25] ARM: dts: bcm2837: Add the missing L1/L2 cache information

Sasha Levin sashal at kernel.org
Wed Mar 30 04:52:07 PDT 2022


From: Richard Schleich <rs at noreya.tech>

[ Upstream commit bdf8762da268d2a34abf517c36528413906e9cd5 ]

This patch fixes the kernel warning
"cacheinfo: Unable to detect cache hierarchy for CPU 0"
for the bcm2837 on newer kernel versions.

Signed-off-by: Richard Schleich <rs at noreya.tech>
Tested-by: Stefan Wahren <stefan.wahren at i2se.com>
[florian: Align and remove comments matching property values]
Signed-off-by: Florian Fainelli <f.fainelli at gmail.com>
Signed-off-by: Sasha Levin <sashal at kernel.org>
---
 arch/arm/boot/dts/bcm2837.dtsi | 49 ++++++++++++++++++++++++++++++++++
 1 file changed, 49 insertions(+)

diff --git a/arch/arm/boot/dts/bcm2837.dtsi b/arch/arm/boot/dts/bcm2837.dtsi
index beb6c502dadc..bcad098a7fcc 100644
--- a/arch/arm/boot/dts/bcm2837.dtsi
+++ b/arch/arm/boot/dts/bcm2837.dtsi
@@ -38,12 +38,26 @@
 		#size-cells = <0>;
 		enable-method = "brcm,bcm2836-smp"; // for ARM 32-bit
 
+		/* Source for d/i-cache-line-size and d/i-cache-sets
+		 * https://developer.arm.com/documentation/ddi0500/e/level-1-memory-system
+		 * /about-the-l1-memory-system?lang=en
+		 *
+		 * Source for d/i-cache-size
+		 * https://magpi.raspberrypi.com/articles/raspberry-pi-3-specs-benchmarks
+		 */
 		cpu0: cpu at 0 {
 			device_type = "cpu";
 			compatible = "arm,cortex-a53";
 			reg = <0>;
 			enable-method = "spin-table";
 			cpu-release-addr = <0x0 0x000000d8>;
+			d-cache-size = <0x8000>;
+			d-cache-line-size = <64>;
+			d-cache-sets = <128>; // 32KiB(size)/64(line-size)=512ways/4-way set
+			i-cache-size = <0x8000>;
+			i-cache-line-size = <64>;
+			i-cache-sets = <256>; // 32KiB(size)/64(line-size)=512ways/2-way set
+			next-level-cache = <&l2>;
 		};
 
 		cpu1: cpu at 1 {
@@ -52,6 +66,13 @@
 			reg = <1>;
 			enable-method = "spin-table";
 			cpu-release-addr = <0x0 0x000000e0>;
+			d-cache-size = <0x8000>;
+			d-cache-line-size = <64>;
+			d-cache-sets = <128>; // 32KiB(size)/64(line-size)=512ways/4-way set
+			i-cache-size = <0x8000>;
+			i-cache-line-size = <64>;
+			i-cache-sets = <256>; // 32KiB(size)/64(line-size)=512ways/2-way set
+			next-level-cache = <&l2>;
 		};
 
 		cpu2: cpu at 2 {
@@ -60,6 +81,13 @@
 			reg = <2>;
 			enable-method = "spin-table";
 			cpu-release-addr = <0x0 0x000000e8>;
+			d-cache-size = <0x8000>;
+			d-cache-line-size = <64>;
+			d-cache-sets = <128>; // 32KiB(size)/64(line-size)=512ways/4-way set
+			i-cache-size = <0x8000>;
+			i-cache-line-size = <64>;
+			i-cache-sets = <256>; // 32KiB(size)/64(line-size)=512ways/2-way set
+			next-level-cache = <&l2>;
 		};
 
 		cpu3: cpu at 3 {
@@ -68,6 +96,27 @@
 			reg = <3>;
 			enable-method = "spin-table";
 			cpu-release-addr = <0x0 0x000000f0>;
+			d-cache-size = <0x8000>;
+			d-cache-line-size = <64>;
+			d-cache-sets = <128>; // 32KiB(size)/64(line-size)=512ways/4-way set
+			i-cache-size = <0x8000>;
+			i-cache-line-size = <64>;
+			i-cache-sets = <256>; // 32KiB(size)/64(line-size)=512ways/2-way set
+			next-level-cache = <&l2>;
+		};
+
+		/* Source for cache-line-size + cache-sets
+		 * https://developer.arm.com/documentation/ddi0500
+		 * /e/level-2-memory-system/about-the-l2-memory-system?lang=en
+		 * Source for cache-size
+		 * https://datasheets.raspberrypi.com/cm/cm1-and-cm3-datasheet.pdf
+		 */
+		l2: l2-cache0 {
+			compatible = "cache";
+			cache-size = <0x80000>;
+			cache-line-size = <64>;
+			cache-sets = <512>; // 512KiB(size)/64(line-size)=8192ways/16-way set
+			cache-level = <2>;
 		};
 	};
 };
-- 
2.34.1




More information about the linux-arm-kernel mailing list