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Date:   Mon, 22 Jul 2019 09:51:16 -0600
From:   Lina Iyer <ilina@codeaurora.org>
To:     Stephen Boyd <swboyd@chromium.org>
Cc:     andy.gross@linaro.org, bjorn.andersson@linaro.org,
        linux-arm-msm@vger.kernel.org, linux-soc@vger.kernel.org,
        rnayak@codeaurora.org, linux-kernel@vger.kernel.org,
        linux-pm@vger.kernel.org, dianders@chromium.org,
        mkshah@codeaurora.org
Subject: Re: [PATCH 2/2] drivers: qcom: rpmh-rsc: fix read back of trigger
 register
Message-ID: <20190722155116.GF25567@codeaurora.org>
References: <20190701152907.16407-1-ilina@codeaurora.org>
 <20190701152907.16407-2-ilina@codeaurora.org>
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On Fri, Jul 19 2019 at 12:22 -0600, Stephen Boyd wrote:
>Quoting Lina Iyer (2019-07-01 08:29:07)
>> When triggering a TCS to send its contents, reading back the trigger
>> value may return an incorrect value. That is because, writing the
>> trigger may raise an interrupt which could be handled immediately and
>> the trigger value could be reset in the interrupt handler. By doing a
>> read back we may end up spinning waiting for the value we wrote.
>
>Doesn't this need to be squashed into the patch that gets rid of the
>irqs disabled state of this code? It sounds an awful lot like this
>problem only happens now because the previous patch removed the
>irqsave/irqrestore code around this function.
>

True. Could be rolled into that fix.

--Lina