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: <f58077fd-3d12-4094-7d46-e49f25e16033@quicinc.com>
Date:   Thu, 15 Sep 2022 18:59:36 +0530
MIME-Version: 1.0
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101
 Thunderbird/91.12.0
Subject: Re: [PATCH 3/3] clk: qcom: gcc-sc7280: Update the .pwrsts for usb
 gdsc
Content-Language: en-US
From:   Rajendra Nayak <quic_rjendra@quicinc.com>
To:     Matthias Kaehlcke <mka@chromium.org>,
        Johan Hovold <johan@kernel.org>
CC:     <andersson@kernel.org>, <agross@kernel.org>,
        <konrad.dybcio@somainline.org>, <mturquette@baylibre.com>,
        <sboyd@kernel.org>, <johan+linaro@kernel.org>,
        <quic_kriskura@quicinc.com>, <dianders@chromium.org>,
        <linux-clk@vger.kernel.org>, <linux-arm-msm@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>
References: <20220901101756.28164-1-quic_rjendra@quicinc.com>
 <20220901101756.28164-3-quic_rjendra@quicinc.com>
 <YxDYJ+ONryLROBhL@google.com> <YyF+5CQqcLQlXvzV@hovoldconsulting.com>
 <YyJGNR33JbHxWWYD@google.com>
 <4490d181-7bf2-791c-1778-1102e9adbc25@quicinc.com>
In-Reply-To: <4490d181-7bf2-791c-1778-1102e9adbc25@quicinc.com>
Content-Type: text/plain; charset="UTF-8"; format=flowed
Content-Transfer-Encoding: 7bit
Precedence: bulk


On 9/15/2022 12:55 PM, Rajendra Nayak wrote:
> 
> 
> On 9/15/2022 2:53 AM, Matthias Kaehlcke wrote:
>> On Wed, Sep 14, 2022 at 09:12:36AM +0200, Johan Hovold wrote:
>>> On Thu, Sep 01, 2022 at 09:04:55AM -0700, Matthias Kaehlcke wrote:
>>>> On Thu, Sep 01, 2022 at 03:47:56PM +0530, Rajendra Nayak wrote:
>>>>> USB on sc7280 cannot support wakeups from low power states
>>>>> if the GDSC is turned OFF. Update the .pwrsts for usb GDSC so it
>>>>> only transitions to RET in low power.
>>>>>
>>>>> Signed-off-by: Rajendra Nayak <quic_rjendra@quicinc.com>
>>>>
>>>> Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
>>>> Tested-by: Matthias Kaehlcke <mka@chromium.org>
>>>
>>> Did you confirm that you actually hit the retention state?
>>
>> No, how would I do that?
>>
>>> IIUC, this series is equivalent to using ALWAYS_ON unless CX is actually
>>> powered off during suspend.
>>
>> The count in /sys/kernel/debug/qcom_stats/cxsd increses with each suspend,
>> however it also does that with the GDSC configured as ALWAYS_ON and with
>> Rajendra's "arm64: dts: qcom: sc7280: Add required-opps for USB" [1], so
> 
> hmm, that's really not expected. With my above patch and with the GDSC as
> ALWAYS_ON there is a cx vote in suspend preventing cxsd so the counter
> should not go up.

Perhaps you are missing '1b771839: clk: qcom: gdsc: enable optional power domain support'
in your tree?

> 
>> I guess that isn't the correct signal.
>>
>> https://patchwork.kernel.org/project/linux-arm-msm/patch/20220914053017.23617-1-quic_rjendra@quicinc.com/