From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Warren Subject: Re: [PATCH 62/62] ARM: tegra: make debug_ll code build for ARMv6 Date: Wed, 19 Mar 2014 14:12:08 -0600 Message-ID: <5329FA18.6090208@wwwdotorg.org> References: <1395257399-359545-1-git-send-email-arnd@arndb.de> <1395257399-359545-63-git-send-email-arnd@arndb.de> <5329F296.6030308@wwwdotorg.org> <6268308.cWSbPODKo9@wuerfel> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <6268308.cWSbPODKo9@wuerfel> Sender: linux-tegra-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Arnd Bergmann 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 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