From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jernej Skrabec Subject: Re: [PATCH v7 0/8] drm: sun8i: Add DE2 HDMI video support Date: Tue, 29 Nov 2016 14:47:20 -0800 (PST) Message-ID: <8398357e-5c5e-4d76-9022-1c668aff5076@googlegroups.com> References: <20161129213650.uqcgekodq77wlmxs@lukather> Reply-To: jernej.skrabec-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="----=_Part_920_701122045.1480459640752" Return-path: Sender: linux-sunxi-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org In-Reply-To: <20161129213650.uqcgekodq77wlmxs@lukather> List-Post: , List-Help: , List-Archive: , List-Unsubscribe: , To: linux-sunxi Cc: moinejf-GANU6spQydw@public.gmane.org, airlied-cv59FeDIM0c@public.gmane.org, robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, dri-devel-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, laurent.pinchart-ryLnwIuWjnjg/C1BVhZhaw@public.gmane.org, maxime.ripard-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org List-Id: devicetree@vger.kernel.org ------=_Part_920_701122045.1480459640752 Content-Type: multipart/alternative; boundary="----=_Part_921_2032391095.1480459640753" ------=_Part_921_2032391095.1480459640753 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Hi Maxime, Dne torek, 29. november 2016 22.37.03 UTC+1 je oseba Maxime Ripard napisala= : > > On Tue, Nov 29, 2016 at 11:18:35AM +0100, Jean-Francois Moine wrote:=20 > > This patchset series adds HDMI video support to the Allwinner=20 > > sun8i SoCs which include the display engine 2 (DE2).=20 > > The driver contains the code for the A83T and H3 SoCs, and=20 > > some H3 boards, but it could be used/extended for other SoCs=20 > > (A64, H2, H5) and boards (Banana PIs, Orange PIs).=20 > > Honestly, I'm getting a bit worried by the fact that you ignore=20 > reviews.=20 > > On the important reviews that you got that are to be seen as major=20 > issues that block the inclusion, we have:=20 > - The fact that the HDMI driver is actually just a designware IP,=20 > and while you should use the driver that already exists, you just=20 > duplicated all that code.=20 > > =20 That might be hard thing to do. A83T fits perfectly, but H3 and newer SoCs= =20 do not. They are using completely different HDMI phy. Decoupling controller an= d phy code means rewritting a good portion of the code, unless some tricks ar= e applied, like calling phy function pointers, if they are defined. Register addresses also differ, but that can be easily solved by using undocumented magic value to restore them. =20 > - The fact that you ignored Rob (v6) and I (v5) comment on using OF=20 > graph to model the connection between the display engine and the=20 > TCON. Something that Laurent also pointed out in this version.=20 > > - The fact that you ignored that you needed an HDMI connector node=20 > as a child of the HDMI controller. This has been reported by Rob=20 > (v6) and yet again in this version by Laurent.=20 > > - And finally the fact that we can't have several display engine in=20 > parallel, if needs be. This has happened in the past already on=20 > Allwinner SoCs, so it's definitely something we should consider in=20 > the DT bindings, since we can't break them.=20 > > Until those are fixed, I cannot see how this driver can be merged,=20 > unfortunately.=20 > > Maxime=20 > > --=20 > Maxime Ripard, Free Electrons=20 > Embedded Linux and Kernel engineering=20 > http://free-electrons.com Best regards, Jernej =C5=A0krabec=20 --=20 You received this message because you are subscribed to the Google Groups "= linux-sunxi" group. To unsubscribe from this group and stop receiving emails from it, send an e= mail to linux-sunxi+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org For more options, visit https://groups.google.com/d/optout. ------=_Part_921_2032391095.1480459640753 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
Hi Maxime,

Dne torek, 29. november 2016 22.37.03 UT= C+1 je oseba Maxime Ripard napisala:
On Tue, Nov 29, 2016 at 11:18:35AM +0100, Jean-Francois Moine wrote:
> This patchset series adds HDMI video support to the Allwinner
> sun8i SoCs which include the display engine 2 (DE2).
> The driver contains the code for the A83T and H3 SoCs, and
> some H3 boards, but it could be used/extended for other SoCs
> (A64, H2, H5) and boards (Banana PIs, Orange PIs).

Honestly, I'm getting a bit worried by the fact that you ignore
reviews.

On the important reviews that you got that are to be seen as major
issues that block the inclusion, we have:
=C2=A0 - The fact that the HDMI driver is actually just a designware IP= ,
=C2=A0 =C2=A0 and while you should use the driver that already exists, = you just
=C2=A0 =C2=A0 duplicated all that code.

=C2=A0
That might be hard thing to do. A83T= fits perfectly, but H3 and newer SoCs do
not. They are using completely= different HDMI phy. Decoupling controller and
phy code means rewritting= a good portion of the code, unless some tricks are
applied, like callin= g phy function pointers, if they are defined.

Register addresses als= o differ, but that can be easily solved by using
undocumented magic valu= e to restore them.
=C2=A0
=C2=A0 - The fact that you ignored Rob (v6) and I (v5) comment on usi= ng OF
=C2=A0 =C2=A0 graph to model the connection between the display engine = and the
=C2=A0 =C2=A0 TCON. Something that Laurent also pointed out in this ver= sion.

=C2=A0 - The fact that you ignored that you needed an HDMI connector no= de
=C2=A0 =C2=A0 as a child of the HDMI controller. This has been reported= by Rob
=C2=A0 =C2=A0 (v6) and yet again in this version by Laurent.

=C2=A0 - And finally the fact that we can't have several display en= gine in
=C2=A0 =C2=A0 parallel, if needs be. This has happened in the past alre= ady on
=C2=A0 =C2=A0 Allwinner SoCs, so it's definitely something we shoul= d consider in
=C2=A0 =C2=A0 the DT bindings, since we can't break them.

Until those are fixed, I cannot see how this driver can be merged,
unfortunately.

Maxime

--=20
Maxime Ripard, Free Electrons
Embedded Linux and Kernel engineering
http://free= -electrons.com

Best regards,
Jernej =C5=A0krabe= c

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