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Subject: Re: [PATCH 4/4] spi: sun6i: add support for R329 SPI controllers
From:   Icenowy Zheng <icenowy@aosc.io>
To:     Samuel Holland <samuel@sholland.org>,
        Mark Brown <broonie@kernel.org>, Chen-Yu Tsai <wens@csie.org>,
        Jernej Skrabec <jernej.skrabec@gmail.com>,
        Maxime Ripard <mripard@kernel.org>
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        linux-arm-kernel@lists.infradead.org, linux-sunxi@lists.linux.dev,
        linux-kernel@vger.kernel.org
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Date:   Sat, 23 Apr 2022 08:01:00 +0800
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在 2022-04-22星期五的 18:59 -0500，Samuel Holland写道：
> On 4/22/22 10:56 AM, icenowy@outlook.com wrote:
> > From: Icenowy Zheng <icenowy@aosc.io>
> > 
> > R329 has two SPI controllers. One of it is quite similar to
> > previous
> > ones, but with internal clock divider removed; the other added MIPI
> > DBI
> > Type-C offload based on the first one.
> > 
> > Add basical support for these controllers. As we're not going to
> > support the DBI functionality now, just implement the two kinds of
> > controllers as the same.
> 
> I'm curious what speeds you were able to use SPI at. On D1, with
> effectively
> these same changes, I would always get corrupted data when reading
> from the
> onboard SPI NAND on the Nezha board. However, if I enabled the "new
> mode of
> sample timing" (bit 2 in GBL_CTL_REG), I got the correct data.

Oh my usage never read from device now, because it's a write-only MIPI
DBI panel.

> 
> Regards,
> Samuel