From mboxrd@z Thu Jan  1 00:00:00 1970
From: Tony Lindgren <tony@atomide.com>
Subject: Re: [PATCH 5/5] arm: boot: store ATAGs structure into DT
 "/chosen/linux,atags" entry
Date: Fri, 27 Nov 2015 06:51:32 -0800
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To: Pali =?utf-8?B?Um9ow6Fy?= <pali.rohar@gmail.com>
Cc: Frank Rowand <frowand.list@gmail.com>, Arnd Bergmann <arnd@arndb.de>, Pavel Machek <pavel@ucw.cz>, "devicetree@vger.kernel.org" <devicetree@vger.kernel.org>, Russell King - ARM Linux <linux@arm.linux.org.uk>, Laura Abbott <lauraa@codeaurora.org>, Grant Likely <grant.likely@linaro.org>, Rob Herring <robherring2@gmail.com>, Will Deacon <will.deacon@arm.com>, Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com>, Sebastian Reichel <sre@debian.org>, Andreas =?utf-8?Q?F=C3=A4rber?= <afaerber@suse.de>, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-omap@vger.kernel.org
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* Pali Roh=C3=A1r <pali.rohar@gmail.com> [151127 00:39]:
> On Thursday 26 November 2015 12:39:30 Tony Lindgren wrote:
> > Just to explore options.. How about make a minimal device driver th=
at
> > just loads the atags blob from /lib/firmware and then shows it in
> > /proc/atags? Of course some checking on the atags should be done by
> > the driver..
>=20
> And who can dynamically create that blob file in /lib/firmware? If
> kernel does not export those atags (somehow) from bootloader, then
> userspace is not able to create that blob... cyclic problem.
>=20
> So no, problem is that bootloader provides via custom atags dynamic
> information like: boot reason (how was device started, by rtc alarm? =
by
> reboot? by usb charger? by power button?), boot mode (should be enter
> into firmware update mode?, is this normal boot mode?), ... and those
> information are needed for some proprietary software (e.g. firmware
> upgrade/flash) but also by any other open source applications (based =
on
> usb charger we enter different runlevel -- for just only charging
> device).

OK if the ATAGs are not static then naturally we can't create the blobs
then.

Regards,

Tony