[PATCH V2 2/3] soc: qcom: boot_stat: Add Driver Support for Boot Stats

Souradeep Chowdhury quic_schowdhu at quicinc.com
Wed Apr 12 07:25:19 PDT 2023



On 4/12/2023 1:51 PM, Krzysztof Kozlowski wrote:
> On 07/04/2023 16:04, Souradeep Chowdhury wrote:
>> All of Qualcomm's proprietary Android boot-loaders capture boot time
>> stats, like the time when the bootloader started execution and at what
>> point the bootloader handed over control to the kernel etc. in the IMEM
>> region. This information is captured in a specific format by this driver
>> by mapping a structure to the IMEM memory region and then accessing the
>> members of the structure to print the information. This information is
>> useful in verifying if the existing boot KPIs have regressed or not.
>> A sample log in SM8450(waipio) device is as follows:-
>>
> 
> 
>> +
>> +static int boot_stats_probe(struct platform_device *pdev)
>> +{
>> +	struct device_node *np_mpm2;
>> +	struct device *boot_stat = &pdev->dev;
>> +
>> +	boot_stats = of_iomap(boot_stat->of_node->child, 0);
>> +	if (!boot_stats)
>> +		return dev_err_probe(&pdev->dev, -ENOMEM,
>> +					"failed to map imem region\n");
>> +
>> +	np_mpm2 = of_find_compatible_node(NULL, NULL,
>> +					  "qcom,mpm2-sleep-counter");
> 
> This is undocumented and non-existing compatible. No, we cannot take this.
> 
> Also, referencing other nodes should be with phandles, not compatibles.

Ack. This will be dropped in the next version as we are not printing the
current kernel timestamp.

> 
> 
> Best regards,
> Krzysztof
> 



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