From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnd Bergmann Subject: Re: [PATCH 62/62] ARM: tegra: make debug_ll code build for ARMv6 Date: Thu, 20 Mar 2014 11:50:16 +0100 Message-ID: <201403201150.16963.arnd@arndb.de> References: <1395257399-359545-1-git-send-email-arnd@arndb.de> <6268308.cWSbPODKo9@wuerfel> <5329FA18.6090208@wwwdotorg.org> Mime-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <5329FA18.6090208-3lzwWm7+Weoh9ZMKESR00Q@public.gmane.org> Sender: linux-tegra-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Stephen Warren Cc: arm-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, Thierry Reding , linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-tegra@vger.kernel.org On Wednesday 19 March 2014, Stephen Warren wrote: > On 03/19/2014 01:51 PM, Arnd Bergmann wrote: > > On Wednesday 19 March 2014 13:40:06 Stephen Warren wrote: > >> Hmmm. This code is guaranteed to only execute on Tegra (well, perhaps > >> someone can turn on the wrong debug option and run it on non-Tegra, but > >> then it's guaranteed not to work since the HW it touches doesn't exist). > >> As such, the code ought to be able to use ARMv7 instructions. > >> > >> As a fix for similar issues in assembly code in arch/arm/mach-tegra/*.S, > >> Makefile there does: > >> > >> asflags-y += -march=armv7-a > >> > >> (I think you added that? Yes, in 408e713545ca "ARM: tegra: build > >> assembly files with -march=armv7-a") > >> > >> Shouldn't we use the same fix in this case too? > > > > That was my first idea, but I couldn't come up with a nice way to do this > > for arch/arm/kernel/debug.S, which #includes the specific implementation. > > > > I'd rather not put lots of per-platform hacks into arch/arm/kernel/Makefile. > > Oh, I guess the fact it's include makes it a bit more painful. > > You could deal with it in Kconfig reasonably easily by having each of > DEBUG_*_UART select a config option indicating how to compile code that > includes DEBUG_LL_INCLUDE, and then have the Makefiles set up asflags > based on those. Still, that would be a lot of work and this patch is > simpler. > > Tested-by: Stephen Warren > Acked-by: Stephen Warren Ok, thanks for testing! I'm always cautious aobut my own assembly skills, so I'm glad this worked. Arnd