linux-kernel - Re: [PATCH 00/14] Add initial support for the Rockchip RK3588 HDMI TX Controller

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20240603-noisy-convivial-boa-d3d862@houat>
Date: Mon, 3 Jun 2024 18:22:05 +0200
From: Maxime Ripard <mripard@...nel.org>
To: Heiko Stuebner <heiko@...ech.de>
Cc: neil.armstrong@...aro.org, 
	Cristian Ciocaltea <cristian.ciocaltea@...labora.com>, Andrzej Hajda <andrzej.hajda@...el.com>, 
	Robert Foss <rfoss@...nel.org>, Laurent Pinchart <Laurent.pinchart@...asonboard.com>, 
	Jonas Karlman <jonas@...boo.se>, Jernej Skrabec <jernej.skrabec@...il.com>, 
	Maarten Lankhorst <maarten.lankhorst@...ux.intel.com>, Thomas Zimmermann <tzimmermann@...e.de>, 
	David Airlie <airlied@...il.com>, Daniel Vetter <daniel@...ll.ch>, 
	Sandy Huang <hjc@...k-chips.com>, Rob Herring <robh@...nel.org>, 
	Krzysztof Kozlowski <krzk+dt@...nel.org>, Conor Dooley <conor+dt@...nel.org>, 
	Mark Yao <markyao0591@...il.com>, Andy Yan <andy.yan@...k-chips.com>, 
	dri-devel@...ts.freedesktop.org, linux-kernel@...r.kernel.org, 
	linux-arm-kernel@...ts.infradead.org, linux-rockchip@...ts.infradead.org, devicetree@...r.kernel.org, 
	kernel@...labora.com, Alexandre ARNOUD <aarnoud@...com>, 
	Luis de Arquer <ldearquer@...il.com>, Algea Cao <algea.cao@...k-chips.com>
Subject: Re: [PATCH 00/14] Add initial support for the Rockchip RK3588 HDMI
 TX Controller

On Mon, Jun 03, 2024 at 03:03:12PM GMT, Heiko Stuebner wrote:
> Am Montag, 3. Juni 2024, 14:14:17 CEST schrieb Andy Yan:
> > Hi Neil:
> > 
> > On 6/3/24 16:55, Neil Armstrong wrote:
> > > Hi Christian,
> > > 
> > > On 01/06/2024 15:12, Cristian Ciocaltea wrote:
> > >> The RK3588 SoC family integrates a Quad-Pixel (QP) variant of the
> > >> Synopsys DesignWare HDMI TX controller used in the previous SoCs.
> > >>
> > >> It is HDMI 2.1 compliant and supports the following features, among
> > >> others:
> > >>
> > > .
> > > 
> > > ..
> > > 
> > >> * SCDC I2C DDC access
> > >> * TMDS Scrambler enabling 2160p@...z with RGB/YCbCr4:4:4
> > >> * YCbCr4:2:0 enabling 2160p@...z at lower HDMI link speeds
> > >> * Multi-stream audio
> > >> * Enhanced Audio Return Channel (EARC)
> > > -> Those features were already supported by the HDMI 2.0a compliant HW, just
> > > list the _new_ features for HDMI 2.1
> > > 
> > > I did a quick review of your patchset and I don't understand why you need
> > > to add a separate dw-hdmi-qp.c since you only need simple variants of the I2C
> > > bus, infoframe and bridge setup.
> > > 
> > > Can you elaborate further ? isn't this Quad-Pixel (QP) TX controller version
> > > detectable at runtime ?
> > > 
> > > I would prefer to keep a single dw-hdmi driver if possible.
> >
> > The QP HDMI controller is a completely different variant with totally different
> > registers layout, see PATCH 13/14.
> > I think make it a separate driver will be easier for development and maintenance.
> 
> I'm with Andy here. Trying to navigate a driver for two IP blocks really
> sounds taxing especially when both are so different.

If it's a completely new controller, I agree that it needs a new driver,
but then why do we need to share code between the two?

Maxime

Download attachment "signature.asc" of type "application/pgp-signature" (274 bytes)