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;
Date:   Fri, 17 Jun 2022 12:14:21 +0530
From:   Viresh Kumar <viresh.kumar@linaro.org>
To:     Vladimir Zapolskiy <vladimir.zapolskiy@linaro.org>
Cc:     Stephen Boyd <swboyd@chromium.org>, linux-kernel@vger.kernel.org,
        patches@lists.linux.dev, linux-pm@vger.kernel.org,
        linux-arm-msm@vger.kernel.org,
        "Rafael J. Wysocki" <rafael@kernel.org>,
        Rob Clark <robdclark@chromium.org>,
        Bjorn Andersson <bjorn.andersson@linaro.org>,
        Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Subject: Re: [PATCH] cpufreq: qcom-hw: Don't do lmh things without a throttle
 interrupt
Message-ID: <20220617064421.l4vshytmqtittzee@vireshk-i7>
References: <20220616224531.3139080-1-swboyd@chromium.org>
 <ce6106e5-3dfd-c2e7-07b9-91be9aef2cf4@linaro.org>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <ce6106e5-3dfd-c2e7-07b9-91be9aef2cf4@linaro.org>
Precedence: bulk

On 17-06-22, 03:21, Vladimir Zapolskiy wrote:
> On 6/17/22 01:45, Stephen Boyd wrote:
> > Offlining cpu6 and cpu7 and then onlining cpu6 hangs on
> > sc7180-trogdor-lazor because the throttle interrupt doesn't exist.
> > Similarly, things go sideways when suspend/resume runs. That's because
> > the qcom_cpufreq_hw_cpu_online() and qcom_cpufreq_hw_lmh_exit()
> > functions are calling genirq APIs with an interrupt value of '-6', i.e.
> > -ENXIO, and that isn't good.
> > 
> > Check the value of the throttle interrupt like we already do in other
> > functions in this file and bail out early from lmh code to fix the hang.
> > 
> > Reported-by: Rob Clark <robdclark@chromium.org>
> > Cc: Vladimir Zapolskiy <vladimir.zapolskiy@linaro.org>
> > Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
> > Cc: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> > Fixes: a1eb080a0447 ("cpufreq: qcom-hw: provide online/offline operations")
> > Signed-off-by: Stephen Boyd <swboyd@chromium.org>
> > ---
> >   drivers/cpufreq/qcom-cpufreq-hw.c | 6 ++++++
> >   1 file changed, 6 insertions(+)
> > 
> > diff --git a/drivers/cpufreq/qcom-cpufreq-hw.c b/drivers/cpufreq/qcom-cpufreq-hw.c
> > index 0253731d6d25..36c79580fba2 100644
> > --- a/drivers/cpufreq/qcom-cpufreq-hw.c
> > +++ b/drivers/cpufreq/qcom-cpufreq-hw.c
> > @@ -442,6 +442,9 @@ static int qcom_cpufreq_hw_cpu_online(struct cpufreq_policy *policy)
> >   	struct platform_device *pdev = cpufreq_get_driver_data();
> >   	int ret;
> > +	if (data->throttle_irq <= 0)
> > +		return 0;
> > +
> >   	ret = irq_set_affinity_hint(data->throttle_irq, policy->cpus);
> >   	if (ret)
> >   		dev_err(&pdev->dev, "Failed to set CPU affinity of %s[%d]\n",
> > @@ -469,6 +472,9 @@ static int qcom_cpufreq_hw_cpu_offline(struct cpufreq_policy *policy)
> >   static void qcom_cpufreq_hw_lmh_exit(struct qcom_cpufreq_data *data)
> >   {
> > +	if (data->throttle_irq <= 0)
> > +		return;
> > +
> >   	free_irq(data->throttle_irq, data);
> >   }
> > 
> Reviewed-by: Vladimir Zapolskiy <vladimir.zapolskiy@linaro.org>

Applied. Thanks.

-- 
viresh