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From:   Stephen Boyd <swboyd@chromium.org>
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Date:   Thu, 19 Aug 2021 11:55:19 -0700
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Subject: Re: [PATCH v5 02/13] dt-bindings: remoteproc: qcom: pas: Add QMP property
To:     Sibi Sankar <sibis@codeaurora.org>, bjorn.andersson@linaro.org,
        mka@chromium.org, robh+dt@kernel.org
Cc:     ulf.hansson@linaro.org, rjw@rjwysocki.net, agross@kernel.org,
        ohad@wizery.com, mathieu.poirier@linaro.org,
        linux-arm-msm@vger.kernel.org, linux-remoteproc@vger.kernel.org,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
        dianders@chromium.org, rishabhb@codeaurora.org,
        sidgup@codeaurora.org
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Quoting Sibi Sankar (2021-08-18 20:02:05)
> The load state power-domain, used by the co-processors to notify the
> Always on Subsystem (AOSS) that a particular co-processor is up/down,
> suffers from the side-effect of changing states during suspend/resume.
> However the co-processors enter low-power modes independent to that of
> the application processor and their states are expected to remain
> unaltered across system suspend/resume cycles. To achieve this behavior
> let's drop the load state power-domain and replace them with the qmp
> property for all SoCs supporting low power mode signalling.
>

How do we drop the load state property without breaking existing DTBs?
Maybe we need to leave it there and then somehow make it optional? Or do
we not care about this problem as the driver will start ignoring it?