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Message-ID: <aec7e2d36b4599f77bc419b8fe7c415815529c2f.camel@collabora.com>
Subject: Re: [PATCH v6 24/30] drm/rockchip: Disable PSR on input events
From:   Ezequiel Garcia <ezequiel@collabora.com>
To:     Enric Balletbo i Serra <enric.balletbo@collabora.com>,
        architt@codeaurora.org, inki.dae@samsung.com,
        thierry.reding@gmail.com, hjc@rock-chips.com,
        seanpaul@chromium.org, airlied@linux.ie, tfiga@chromium.org,
        heiko@sntech.de
Cc:     dri-devel@lists.freedesktop.org, dianders@chromium.org,
        a.hajda@samsung.com, ykk@rock-chips.com, kernel@collabora.com,
        m.szyprowski@samsung.com, linux-samsung-soc@vger.kernel.org,
        jy0922.shim@samsung.com, rydberg@bitmath.org, krzk@kernel.org,
        linux-rockchip@lists.infradead.org, kgene@kernel.org,
        linux-input@vger.kernel.org, orjan.eide@arm.com,
        wxt@rock-chips.com, jeffy.chen@rock-chips.com,
        linux-arm-kernel@lists.infradead.org, mark.yao@rock-chips.com,
        wzz@rock-chips.com, hl@rock-chips.com, jingoohan1@gmail.com,
        sw0312.kim@samsung.com, linux-kernel@vger.kernel.org,
        kyungmin.park@samsung.com, Laurent.pinchart@ideasonboard.com,
        kuankuan.y@gmail.com, hshi@chromium.org,
        "Kristian H. Kristensen" <hoegsberg@google.com>
Date:   Mon, 16 Apr 2018 16:42:29 -0300
In-Reply-To: <20180405095000.9756-25-enric.balletbo@collabora.com>
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         <20180405095000.9756-25-enric.balletbo@collabora.com>
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On Thu, 2018-04-05 at 11:49 +0200, Enric Balletbo i Serra wrote:
> From: "Kristian H. Kristensen" <hoegsberg@google.com>
> 
> To improve PSR exit latency, we speculatively start exiting when we
> receive input events. Occasionally, this may lead to false positives,
> but most of the time we get a head start on coming out of PSR.
> Depending
> on how userspace takes to produce a new frame in response to the
> event,
> this can completely hide the exit latency. In case of Chrome OS, we
> typically get the input notifier 50ms or more before the dirty_fb
> triggered exit.
> 

Why is this rockchip-specific? It sounds more like something
we'd want to integrate generically for drivers to leverage.

Regards,
Eze