From a4366b5695c984b8a3fc8b31de9e758c8f6d1aed Mon Sep 17 00:00:00 2001 From: "Nícolas F. R. A. Prado" Date: Fri, 2 Jun 2023 14:35:15 -0400 Subject: arm64: dts: mediatek: mt8192: Fix CPUs capacity-dmips-mhz MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The capacity-dmips-mhz parameter was miscalculated: this SoC runs the first (Cortex-A55) cluster at a maximum of 2000MHz and the second (Cortex-A76) cluster at a maximum of 2200MHz. In order to calculate the right capacity-dmips-mhz, the following test was performed: 1. CPUFREQ governor was set to 'performance' on both clusters 2. Ran dhrystone with 500000000 iterations for 10 times on each cluster 3. Calculated the mean result for each cluster 4. Calculated DMIPS/MHz: dmips_mhz = dmips_per_second / cpu_mhz 5. Scaled results to 1024: result_c0 = dmips_mhz_c0 / dmips_mhz_c1 * 1024 The mean results for this SoC are: Cluster 0 (LITTLE): 12016411 Dhry/s Cluster 1 (BIG): 31702034 Dhry/s The calculated scaled results are: Cluster 0: 426.953226899238 (rounded to 427) Cluster 1: 1024 Fixes: 48489980e27e ("arm64: dts: Add Mediatek SoC MT8192 and evaluation board dts and Makefile") Signed-off-by: Nícolas F. R. A. Prado Reviewed-by: AngeloGioacchino Del Regno Link: https://lore.kernel.org/r/20230602183515.3778780-1-nfraprado@collabora.com Signed-off-by: Matthias Brugger --- arch/arm64/boot/dts/mediatek/mt8192.dtsi | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/arch/arm64/boot/dts/mediatek/mt8192.dtsi b/arch/arm64/boot/dts/mediatek/mt8192.dtsi index bab403a43c4d..69f4cded5dbb 100644 --- a/arch/arm64/boot/dts/mediatek/mt8192.dtsi +++ b/arch/arm64/boot/dts/mediatek/mt8192.dtsi @@ -71,7 +71,7 @@ d-cache-sets = <128>; next-level-cache = <&l2_0>; performance-domains = <&performance 0>; - capacity-dmips-mhz = <530>; + capacity-dmips-mhz = <427>; }; cpu1: cpu@100 { @@ -89,7 +89,7 @@ d-cache-sets = <128>; next-level-cache = <&l2_0>; performance-domains = <&performance 0>; - capacity-dmips-mhz = <530>; + capacity-dmips-mhz = <427>; }; cpu2: cpu@200 { @@ -107,7 +107,7 @@ d-cache-sets = <128>; next-level-cache = <&l2_0>; performance-domains = <&performance 0>; - capacity-dmips-mhz = <530>; + capacity-dmips-mhz = <427>; }; cpu3: cpu@300 { @@ -125,7 +125,7 @@ d-cache-sets = <128>; next-level-cache = <&l2_0>; performance-domains = <&performance 0>; - capacity-dmips-mhz = <530>; + capacity-dmips-mhz = <427>; }; cpu4: cpu@400 { -- cgit v1.2.3