From mboxrd@z Thu Jan  1 00:00:00 1970
From: Albert ARIBAUD <albert.u.boot@aribaud.net>
Date: Wed, 21 Oct 2015 13:42:27 +0200
Subject: [U-Boot] [PATCH V2 1/3] arm: discard relocation entry for
	secure section
In-Reply-To: <20151021094216.GA29761@shlinux2>
References: <1445320795-2235-1-git-send-email-Peng.Fan@freescale.com>
 <20151020090532.48426615@lilith> <20151020072039.GA26880@shlinux2>
 <20151020093251.468ebaa0@lilith> <20151020074127.GA31531@shlinux2>
 <20151020145910.5e40f8cf@lilith> <20151021094216.GA29761@shlinux2>
Message-ID: <20151021134227.55a71b8c@lilith>
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To: u-boot@lists.denx.de

Hello Peng,

On Wed, 21 Oct 2015 17:42:20 +0800, Peng Fan <b51431@freescale.com>
wrote:
> Hello Albert,

> I do not know how to generate non-relocatable code only for the secure text.
> Since -mword-relocations and -pie are global flags, I do not know how to disable
> mword-relocations when compiling PSCI and other secure text.

Actually, I haven't even found a compiler or gcc option to entirely
remove relocations altogether.

> Is this ok for you?
> 
> diff --git a/arch/arm/cpu/u-boot.lds b/arch/arm/cpu/u-boot.lds
> index 65986e8..fb2128a 100644
> --- a/arch/arm/cpu/u-boot.lds
> +++ b/arch/arm/cpu/u-boot.lds
> @@ -14,6 +14,7 @@ OUTPUT_ARCH(arm)
> ENTRY(_start)
> SECTIONS
> {
> +       /DISCARD/ : { *(.rel._secure*) }
>         . = 0x00000000;
>    
>         . = ALIGN(4);

Functionally, it works -- I've just checked it by comparing u-boot.map
files of a mx7dsabresd build with and without the DISCARD. Not a single
symbol from the text and data section gets changed.

The only missing thing left is a comment before the DISCARD line,
explaining both why .rel._secure* input sections have to be discarded,
and also explaining why this is done it right at the start of the output
sections.

Thanks for your patience. :)

> Regards,
> Peng.

Amicalement,
-- 
Albert.