Re: [PATCH V2 3/5] arm64: dts: qcom: Add base X1E80100 dtsi and the QCP dts

[Sibi Sankar <quic_sibis@quicinc.com>]

On 11/18/23 06:36, Konrad Dybcio wrote:
> On 17.11.2023 12:39, Sibi Sankar wrote:
>> From: Rajendra Nayak <quic_rjendra@quicinc.com>
>>
>> Add base dtsi and QCP board (Qualcomm Compute Platform) dts file for
>> X1E80100 SoC, describing the CPUs, GCC and RPMHCC clock controllers,
>> geni UART, interrupt controller, TLMM, reserved memory, interconnects,
>> SMMU and LLCC nodes.
>>
>> Co-developed-by: Abel Vesa <abel.vesa@linaro.org>
>> Signed-off-by: Abel Vesa <abel.vesa@linaro.org>
>> Signed-off-by: Rajendra Nayak <quic_rjendra@quicinc.com>
>> Co-developed-by: Sibi Sankar <quic_sibis@quicinc.com>
>> Signed-off-by: Sibi Sankar <quic_sibis@quicinc.com>
>> ---
> [...]
> 
>> +&tlmm {
>> +	gpio-reserved-ranges = <33 3>, <44 4>, /* SPI (TPM) */
> Surely SPI doesn't use 7 wires! :D

yeah, they are just secure reserved unused gpios.

> 
> [...]
> 
>> +			L2_0: l2-cache-0 {
> the cache device is distinguishable by its parent, so "l2-cache" is enough

thanks will fix ^^

> 
> 
>> +				compatible = "cache";
>> +				cache-level = <2>;
>> +				cache-unified;
>> +			};
>> +		};
>> +
> [...]
> 
>> +		idle-states {
>> +			entry-method = "psci";
>> +
>> +			CLUSTER_C4: cpu-sleep-0 {
>> +				compatible = "arm,idle-state";
>> +				idle-state-name = "ret";
>> +				arm,psci-suspend-param = <0x00000004>;
> These suspend parameters look funky.. is this just a PSCI sleep
> implementation that strays far away from Arm's suggested guidelines?

not really! it's just that 30th bit is set according to spec i.e
it's marked as a retention state.

> 
> [...]
> 
> 
>> +		CPU_PD11: power-domain-cpu11 {
>> +			#power-domain-cells = <0>;
>> +			power-domains = <&CLUSTER_PD>;
>> +		};
>> +
>> +		CLUSTER_PD: power-domain-cpu-cluster {
>> +			#power-domain-cells = <0>;
>> +			domain-idle-states = <&CLUSTER_CL4>, <&CLUSTER_CL5>;
>> +		};
> So, can the 3 clusters not shut down their L2 and PLLs (if separate?)
> on their own?

on CL5 the clusters are expected to shutdown their l2 and PLL on their
own.

> 
>> +	};
>> +
>> +	reserved-memory {
>> +		#address-cells = <2>;
>> +		#size-cells = <2>;
>> +		ranges;
>> +
>> +		gunyah_hyp_mem: gunyah-hyp@80000000 {
>> +			reg = <0x0 0x80000000 0x0 0x800000>;
>> +			no-map;
>> +		};
>> +
>> +		hyp_elf_package_mem: hyp-elf_package@80800000 {
> no underscores in node names, use hyphens

ack

-Sibi
> 
> The rest looks OK I think
> 
> Konrad