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From:   Tong Zhang <ztong0001@gmail.com>
Date:   Sat, 20 Feb 2021 21:34:16 -0500
Message-ID: <CAA5qM4A4Ckcw7R2spuKEUg_xxqyxifgaYvj=Sqo2p04KzSD2Sw@mail.gmail.com>
Subject: Re: [PATCH v2] video: fbdev: pm2fb: avoid stall on fb_sync
To:     Randy Dunlap <rdunlap@infradead.org>
Cc:     "Gustavo A. R. Silva" <gustavoars@kernel.org>,
        Sam Ravnborg <sam@ravnborg.org>,
        Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>,
        dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org,
        open list <linux-kernel@vger.kernel.org>
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On Sat, Feb 20, 2021 at 7:36 PM Randy Dunlap <rdunlap@infradead.org> wrote:
> I suppose the rest of the patch is OK since it works for you.
>
> I don't know any of this code. It would be nice to know what some
> of those pm2_RD(par, SOME_REG) mean so that I could sort of
> understand what it is doing, but don't go spending time on it
> just for me. It's not worth doing that IMO.
>
>
> --
> ~Randy

Thank you Randy. I have sent another revision.
I am also curious about those registers -- but it is hard to
accurately figure it out without datasheet --
my speculation is that it calls the device to do some sort of frame
buffer synchronizations here
Thanks,
- Tong