From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dave P Martin Subject: Re: [PATCH 6/7] Add EFI stub for ARM Date: Tue, 6 Aug 2013 11:31:08 +0100 Message-ID: <20130806103108.GD2791@e103592.cambridge.arm.com> References: <1375478948-22562-1-git-send-email-roy.franz@linaro.org> <1375478948-22562-7-git-send-email-roy.franz@linaro.org> <20130805141149.GB2755@localhost.localdomain> <20130805153318.GL18151@rocoto.smurfnet.nu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20130805153318.GL18151-GZEopFhza0F985/tl1ce8aaDwS/vmuI7@public.gmane.org> Sender: linux-efi-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Leif Lindholm Cc: Roy Franz , "linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "linux-efi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org" , "matt.fleming-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org" , "linux-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org" List-Id: linux-efi@vger.kernel.org On Mon, Aug 05, 2013 at 04:33:19PM +0100, Leif Lindholm wrote: > On Mon, Aug 05, 2013 at 03:11:49PM +0100, Dave Martin wrote: > > > diff --git a/arch/arm/boot/compressed/head.S b/arch/arm/boot/compressed/head.S > > > index 75189f1..4c70b9e 100644 > > > --- a/arch/arm/boot/compressed/head.S > > > +++ b/arch/arm/boot/compressed/head.S > > > @@ -122,19 +122,106 @@ > > > .arm @ Always enter in ARM state > > > start: > > > .type start,#function > > > - .rept 7 > > > +#ifdef CONFIG_EFI_STUB > > > + @ Magic MSDOS signature for PE/COFF + ADD opcode > > > + .word 0x62805a4d > > > > What about BE32? > > The ARM bindings for UEFI specify that the processor must be in > little-endian mode. > > > In that case, the instruction is a coprocessor load, that loads from a > > random address to a coprocessor that almost certainly doesn't exist. > > This will probably fault. > > > > Since BE32 is only for older platforms ( > solvable, it might be sensible to make the EFI stub support depend on > > !CPU_ENDIAN_BE32. > > Well, it would make more sense to make EFI_STUB depend on EFI and > EFI depend on !CPU_ENDIAN_BE32. Which is something I can add to > my next set of general ARM UEFI patches. Thanks. That sounds fair enough. Cheers ---Dave