Re: [PATCH] arm64: dts: qcom: sm8750: add cpu OPP table with DDR and LLCC bandwidths

[Konrad Dybcio]

On 6/6/26 12:36 AM, Aaron Kling via B4 Relay wrote:
> From: Aaron Kling <webgeek1234@xxxxxxxxx>
> 
> Add the OPP tables for each CPU cluster (cpu0-1-2-3-4-5 & cpu6-7) to
> permit scaling the Last Level Cache Controller (LLCC) and DDR frequency
> by aggregating bandwidth requests of all CPU core with reference to the
> current OPP they are configured in by the hardware.
> 
> The effect is proper caches & DDR frequency scaling when CPU cores
> change frequency.
> 
> The OPP tables were built using the downstream memlat ddr & llcc tables
> for each cluster types with the actual cpufreq LUT tables from running a
> CQ8725S device.
> 
> Also add the interconnect entry for each cpu, with 2 different paths:
> - CPU to Last Level Cache Controller (LLCC)
> - Last Level Cache Controller (LLCC) to DDR
> 
> Signed-off-by: Aaron Kling <webgeek1234@xxxxxxxxx>
> ---
> arm64: dts: qcom: sm8750: add cpu OPP table with DDR and LLCC bandwidths
> ---

[...]

> +	cpu6_opp_table: opp-table-cpu6 {
> +		compatible = "operating-points-v2";
> +		opp-shared;
> +
> +		opp-1017600000 {
> +			opp-hz = /bits/ 64 <1017600000>;
> +			opp-peak-kBps = <(1353000 * 16) (350000 * 4)>;

I think this should be * 4 in both cases since the interconnect driver
ignores the channel count for a node in peak voting. We may have a bug
in all other DTs here.

BTW, are there no lower OPPs for the fast cores?

Konrad