Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Message-ID: <d05e1184-ead4-3f80-4c06-ff757a10ba3b@linaro.org>
Date:   Wed, 12 Apr 2023 10:21:18 +0200
MIME-Version: 1.0
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101
 Thunderbird/102.9.1
Subject: Re: [PATCH V2 2/3] soc: qcom: boot_stat: Add Driver Support for Boot
 Stats
Content-Language: en-US
To:     Souradeep Chowdhury <quic_schowdhu@quicinc.com>,
        Andy Gross <agross@kernel.org>,
        Konrad Dybcio <konrad.dybcio@somainline.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Bjorn Andersson <andersson@kernel.org>,
        Rob Herring <robh+dt@kernel.org>
Cc:     linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        linux-arm-msm@vger.kernel.org, devicetree@vger.kernel.org,
        Sibi Sankar <quic_sibis@quicinc.com>,
        Rajendra Nayak <quic_rjendra@quicinc.com>
References: <cover.1680874520.git.quic_schowdhu@quicinc.com>
 <5eeeb46e9b3f61656a37cb77c2ad6a04e383c16d.1680874520.git.quic_schowdhu@quicinc.com>
From:   Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
In-Reply-To: <5eeeb46e9b3f61656a37cb77c2ad6a04e383c16d.1680874520.git.quic_schowdhu@quicinc.com>
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 7bit
Precedence: bulk

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.


Best regards,
Krzysztof