| Message ID | 20081015144359.GA30649@Chamillionaire.breakpoint.cc (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Delegated to: | Kumar Gala |
| Headers | show |
On Oct 15, 2008, at 9:43 AM, Sebastian Andrzej Siewior wrote: > * Kumar Gala | 2008-10-15 08:25:54 [-0500]: > >> >> On Oct 15, 2008, at 3:59 AM, Sebastian Andrzej Siewior wrote: >> >>> * Sebastian Andrzej Siewior | 2008-10-15 00:49:46 [+0200]: >>> >>>>> is the -mabi=no-spe really needed? >>>> It seems to work the other way around (without -mabi=no-spe but >>>> with >>>> -mabi=no-spe) alteast I did not find anything in do_syslog() or >>>> while >>>> browsing through the dissasm. I do a boot check tomorrow. >>> >>> Okay. I recompiled with -mspe=no and was able to boot without >>> trouble. >>> It didn't work with -mabi=no-spe. >> >> I'm confused.. what did you change from your patch? > > This is the patch it right now: > --- a/arch/powerpc/Makefile > +++ b/arch/powerpc/Makefile > @@ -103,6 +103,7 @@ KBUILD_CFLAGS += $(call cc-option,-mno-altivec) > > # No SPE instruction when building kernel > KBUILD_CFLAGS += $(call cc-option,-mno-spe) > +KBUILD_CFLAGS += $(call cc-option,-mspe=no) > > # Enable unit-at-a-time mode when possible. It shrinks the > # kernel considerably. > -- > > With this patch it compiles and boots fine. > The option -mabi=no-spe is not required. ok. can post a clean patch w/just this change. - k
On Wed, 2008-10-15 at 16:43 +0200, Sebastian Andrzej Siewior wrote: > With this patch it compiles and boots fine. > The option -mabi=no-spe is not required. Please don't accept this patch yet. My past testing showed that "-mabi=no-spe" was required for my toolchain. I'll go back and double check though. - Nate Case <ncase@xes-inc.com>
* Nate Case | 2008-10-17 09:02:11 [-0500]: >On Wed, 2008-10-15 at 16:43 +0200, Sebastian Andrzej Siewior wrote: >> With this patch it compiles and boots fine. >> The option -mabi=no-spe is not required. > >Please don't accept this patch yet. My past testing showed that >"-mabi=no-spe" was required for my toolchain. I'll go back and double >check though. Okay. Here my compiler details: | powerpc-linux-gnuspe-gcc -v | Using built-in specs. | Target: powerpc-linux-gnuspe | Configured with: ../src/configure -v --with-pkgversion='Debian 4.3.1-9' | --with-bugurl=file:///usr/share/doc/gcc-4.3/README.Bugs | --enable-languages=c,c++,obj-c++ --prefix=/usr --enable-shared | --with-system-zlib --libexecdir=/usr/lib --without-included-gettext | --enable-threads=posix --enable-nls | --with-gxx-include-dir=/usr/powerpc-linux-gnuspe/include/c++/4.3.1 | --program-suffix=-4.3 --enable-clocale=gnu --enable-libstdcxx-debug | --disable-multilib --disable-multilib --with-cpu=8540 | --enable-e500_double --with-long-double-128 --enable-checking=release | --program-prefix=powerpc-linux-gnuspe- | --includedir=/usr/powerpc-linux-gnuspe/include --build=i486-linux-gnu | --host=i486-linux-gnu --target=powerpc-linux-gnuspe | Thread model: posix | gcc version 4.3.1 (Debian 4.3.1-9) ths told me that we need all three options in this order because of how they interact with gcc's internal flags. >- Nate Case <ncase@xes-inc.com> Sebastian
On Fri, 2008-10-17 at 09:02 -0500, Nate Case wrote: > > With this patch it compiles and boots fine. > > The option -mabi=no-spe is not required. > > Please don't accept this patch yet. My past testing showed that > "-mabi=no-spe" was required for my toolchain. I'll go back and double > check though. OK, I went back and re-tested. Kernel: 2.6.27 CPU: MPC8572 Toolchain: Cross-compiler built using crosstool-ng gcc 4.3.1, default target CFLAGS include '-mabi=spe -mspe' binutils 2.18.90 snapshot (built with --enable-spe=yes) Kbuild flags Result ------------ ------ -mno-spe (*) FAILED -mno-spe -mabi=no-spe FAILED -mno-spe -mspe=no OK -mspe=no OK (*) 2.6.27 default In the failure case, the kernel would repeatedly dump out "SPE used in kernel (task=xxxxxxxx, pc=xxxxxxxx)". I think I was fooled before because I added _both_ "-mspe=no" and "-mabi=no-spe" to my KBUILD_CFLAGS and saw the problem go away. Since I trusted the documentation that -mspe=no and -mno-spe were the same, I assumed that -mabi=no-spe was the key. So, I've changed my mind. I now agree with Sebastian that "-mabi=no-spe" is not required. "-mno-spe -mspe=no" is probably the safe way to go.
On Oct 24, 2008, at 6:51 PM, Nate Case wrote: > On Fri, 2008-10-17 at 09:02 -0500, Nate Case wrote: >>> With this patch it compiles and boots fine. >>> The option -mabi=no-spe is not required. >> >> Please don't accept this patch yet. My past testing showed that >> "-mabi=no-spe" was required for my toolchain. I'll go back and >> double >> check though. > > OK, I went back and re-tested. > > Kernel: 2.6.27 > CPU: MPC8572 > Toolchain: > Cross-compiler built using crosstool-ng > gcc 4.3.1, default target CFLAGS include '-mabi=spe -mspe' > binutils 2.18.90 snapshot (built with --enable-spe=yes) > > Kbuild flags Result > ------------ ------ > -mno-spe (*) FAILED > -mno-spe -mabi=no-spe FAILED > -mno-spe -mspe=no OK > -mspe=no OK > > (*) 2.6.27 default > > In the failure case, the kernel would repeatedly dump out "SPE used in > kernel (task=xxxxxxxx, pc=xxxxxxxx)". > > I think I was fooled before because I added _both_ "-mspe=no" and > "-mabi=no-spe" to my KBUILD_CFLAGS and saw the problem go away. > Since I > trusted the documentation that -mspe=no and -mno-spe were the same, I > assumed that -mabi=no-spe was the key. > > So, I've changed my mind. I now agree with Sebastian that > "-mabi=no-spe" is not required. "-mno-spe -mspe=no" is probably the > safe way to go. > > -- > Nate Case <ncase@xes-inc.com> thanks for testing this all out. I'll submit a patch to remove the -mabi=.*spe.* foo. - k
--- a/arch/powerpc/Makefile +++ b/arch/powerpc/Makefile @@ -103,6 +103,7 @@ KBUILD_CFLAGS += $(call cc-option,-mno-altivec) # No SPE instruction when building kernel KBUILD_CFLAGS += $(call cc-option,-mno-spe) +KBUILD_CFLAGS += $(call cc-option,-mspe=no) # Enable unit-at-a-time mode when possible. It shrinks the # kernel considerably.