linux-kernel - Re: [RFC PATCH 00/10] Support simple-framebuffer on imx8m

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: <20241028-scrupulous-paper-condor-0742fb@houat>
Date: Mon, 28 Oct 2024 11:49:57 +0100
From: Maxime Ripard <mripard@...nel.org>
To: Dario Binacchi <dario.binacchi@...rulasolutions.com>
Cc: linux-kernel@...r.kernel.org, linux-amarula@...rulasolutions.com, 
	Andrey Smirnov <andrew.smirnov@...il.com>, Andrzej Hajda <andrzej.hajda@...el.com>, 
	Conor Dooley <conor+dt@...nel.org>, David Airlie <airlied@...il.com>, 
	Fabio Estevam <festevam@...il.com>, Inki Dae <inki.dae@...sung.com>, 
	Jagan Teki <jagan@...rulasolutions.com>, Jernej Skrabec <jernej.skrabec@...il.com>, 
	Jessica Zhang <quic_jesszhan@...cinc.com>, Jonas Karlman <jonas@...boo.se>, 
	Krzysztof Kozlowski <krzk+dt@...nel.org>, Krzysztof Kozlowski <krzysztof.kozlowski@...aro.org>, 
	Laurent Pinchart <Laurent.pinchart@...asonboard.com>, Lucas Stach <l.stach@...gutronix.de>, 
	Maarten Lankhorst <maarten.lankhorst@...ux.intel.com>, Marek Szyprowski <m.szyprowski@...sung.com>, 
	Marek Vasut <marex@...x.de>, Michael Trimarchi <michael@...rulasolutions.com>, 
	Neil Armstrong <neil.armstrong@...aro.org>, Peng Fan <peng.fan@....com>, 
	Pengutronix Kernel Team <kernel@...gutronix.de>, Rob Herring <robh@...nel.org>, Robert Foss <rfoss@...nel.org>, 
	Sascha Hauer <s.hauer@...gutronix.de>, Shawn Guo <shawnguo@...nel.org>, 
	Shengjiu Wang <shengjiu.wang@....com>, Simona Vetter <simona@...ll.ch>, Stefan Agner <stefan@...er.ch>, 
	Thomas Zimmermann <tzimmermann@...e.de>, Ulf Hansson <ulf.hansson@...aro.org>, 
	Uwe Kleine-König <u.kleine-koenig@...gutronix.de>, devicetree@...r.kernel.org, dri-devel@...ts.freedesktop.org, 
	imx@...ts.linux.dev, linux-arm-kernel@...ts.infradead.org, linux-pm@...r.kernel.org
Subject: Re: [RFC PATCH 00/10] Support simple-framebuffer on imx8m

Hi,

On Mon, Oct 28, 2024 at 11:25:23AM +0100, Dario Binacchi wrote:
> This series is the Linux counterpart of what was sent to U-Boot [1]
> for the support of the simple-framebuffer for the BSH SMM S2Pro board.

I'm confused. simple-framebuffer is a mechanism for which the entire
point is that the kernel doesn't need the driver for.

Why do you need to have patches for bridges and panels for
simple-framebuffer? They won't be used.

> The need to avoid re-initializing the hardware (power domains,
> controllers, bridges, display panels) that has already been initialized
> and kept powered on by the bootloader has required updating more than
> one YAML file, with the addition of boolean properties to inform the
> driver that the corresponding hardware has been initialized and left
> on by the bootloader. All these properties are added on the fly by the
> bootloader to the various relevant nodes.

So it's not about simple-framebuffer at all, but rather that you don't
want to re-initialize the hardware that has already been setup?

If so, this isn't how you should do it, but rather:
https://lore.kernel.org/all/CAKMK7uHtqHy_oz4W7F+hmp9iqp7W5Ra8CxPvJ=9BwmvfU-O0gg@mail.gmail.com/

Maxime

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