From mboxrd@z Thu Jan 1 00:00:00 1970 From: tony@atomide.com (Tony Lindgren) Date: Thu, 23 Dec 2010 11:55:03 -0800 Subject: linux-next: omap2plus_defconfig not building In-Reply-To: <1289209693.3538.5.camel@e102109-lin.cambridge.arm.com> References: <4CBD707F.6050204@ti.com> <1287488255.18646.110.camel@e102109-lin.cambridge.arm.com> <1289209693.3538.5.camel@e102109-lin.cambridge.arm.com> Message-ID: <20101223195503.GN7771@atomide.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org * Catalin Marinas [101108 01:38]: > On Mon, 2010-11-08 at 06:05 +0000, Anand Gadiyar wrote: > > Catalin Marinas wrote: > > > On Tue, 2010-10-19 at 11:18 +0100, Anand Gadiyar wrote: > > > > Commit ba1b9be5cd in linux-next (ARM: Add SWP/SWPB emulation for ARMv7 > > > > processors (v5)) introduced arch/arm/kernel/swp_emulate.c. This file > > > > gets compiled when the omap2plus_defconfig is built - the > > > > omap2plus_defconfig builds OMAP2420, OMAP2430, OMAP3 and OMAP4 in one > > > > image, and has CPU_V6 and CPU_V7 both enabled. > > > > > > This patch should fix it: > > > > > > > > > ARM: Do not enable SWP emulation if CPU_V6 && CPU_V7 > > > > > > From: Catalin Marinas > > > > > > This option uses LDREXB/STREXB to emulate SWPB but these instructions > > > are not supported on all the ARMv6 processors. > > > > > > Reported-by: Anand Gadiyar > > > Signed-off-by: Catalin Marinas > > > Cc: Leif Lindholm > > > > I can't find this patch in linux-next. Hope we haven't missed it. > > Tony acked this btw. > > > > Strangely, the omap2plus_defconfig in v2.6.37-rc1 no longer gets > > CONFIG_SWP_EMULATE enabled even without this patch - I can't figure > > out why. > > Russell had a better idea for handling this, not sure whether it went > into -next. It was basically adding -march=armv7-a to > CFLAGS_swp_emulate.o in arch/arm/kernel/Makefile since we can't trigger > an undef fault for SWP on ARMv6 anyway. > > If it's not in yet, I can submit a patch. Catalin, you patch is still needed until we have a better solution. Looks like the long term solution is to move the _user_swpX_asm into a separate .S file and set the v7 instructions for it. Regards, Tony