Re: [PATCH] arm: dt: Initialize boot_command_line from CONFIG_CMDLINE in case DT does not provide /chosen/bootargs

From: Javier Martinez Canillas <javier@dowhile0.org>
To: "Pali Rohár" <pali.rohar@gmail.com>
Cc: Russell King <linux@armlinux.org.uk>,
	Arnd Bergmann <arnd@arndb.de>,
	Robin Murphy <robin.murphy@arm.com>,
	Linus Walleij <linus.walleij@linaro.org>,
	Ben Dooks <ben-linux@fluff.org>, Tony Lindgren <tony@atomide.com>,
	Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com>,
	Sebastian Reichel <sre@kernel.org>,
	Aaro Koskinen <aaro.koskinen@iki.fi>, Pavel Machek <pavel@ucw.cz>,
	"linux-arm-kernel@lists.infradead.org" 
	<linux-arm-kernel@lists.infradead.org>,
	Linux Kernel <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] arm: dt: Initialize boot_command_line from CONFIG_CMDLINE in case DT does not provide /chosen/bootargs
Date: Wed, 14 Dec 2016 19:22:46 -0300	[thread overview]
Message-ID: <CABxcv=n=FOFedS9vF9qf68PAWy3YQoAMHJcgiG9TiaLrDOZXDw@mail.gmail.com> (raw)
In-Reply-To: <1481749963-8664-1-git-send-email-pali.rohar@gmail.com>

Hello Pali,

On Wed, Dec 14, 2016 at 6:12 PM, Pali Rohár <pali.rohar@gmail.com> wrote:
> Commit 008a2ebcd677 ("ARM: dts: omap3: Remove skeleton.dtsi usage") broke
> support for setting cmdline on Nokia N900 via CONFIG_CMDLINE.
>

This commit really exposed the issue rather than causing it. But since
it was working before due including skeleton.dtsi which defines an
empty chosen node, I think that you should add a:

Fixes: 008a2ebcd677 ("ARM: dts: omap3: Remove skeleton.dtsi usage")

> It is because arm code booted in DT mode parse cmdline only via function
> early_init_dt_scan_chosen() and that function does not fill variable
> boot_command_line when DTB does not contain /chosen entry. It is called
> from function early_init_dt_scan_nodes() in setup_machine_fdt().
>
> This patch fixes it by explicitly filling boot_command_line in function
> setup_machine_fdt() after calling early_init_dt_scan_nodes() in case
> boot_command_line still remains empty.
>
> Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
> ---

Best regards,
Javier