Depending on how GCC is built, GCC 4 may generate altivec instructions without
user explicitly requesting vector operations in the code. Although this is a
performance booster for user applications, it is a problem for kernel.
This patch explicitly instruct GCC to NOT generate altivec instructions while
building the kernel.
Here are some test cases I ran.
(1) build gcc 4.0.1 with '--with-cpu=7450 --enable-altivec
--enable-cxx-flags=-mcpu=7450', and use this gcc to build kernel WITHOUT
this kernel patch. Kernel fail to boot up on a 7450 board because of
altivec instructions in kernel.
(2) build gcc 4.0.1 with "--with-cpu=7450 --enable-altivec
--enable-cxx-flags=-mcpu=7450", and use this gcc to build kernel WITH this
kernel patch. Kernel boot up on a 7450 board without any problem.
(3) build gcc 4.0.1 with "--with-cpu=750 --enable-cxx-flags=-mcpu=750",
and use this gcc to build kernel with or without this kernel patch.
Kernel boot up on a 7450 board without any problem.
This patch should also work with GCC 3 or even earlier GCC 2.95.3.
Signed-off-by: Lee Nicks <allinux@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The merged version follows the ppc64 version pretty closely mostly,
and in fact ARCH=ppc64 now uses the arch/powerpc/xmon version.
The main difference for ppc64 is that the 'p' command to call
show_state (which was always pretty dodgy) has been replaced by
the ppc32 'p' command, which calls a given procedure (so in fact
the old 'p' command behaviour can be achieved with 'p $show_state').
Signed-off-by: Paul Mackerras <paulus@samba.org>
This allows us to also use entry_64.S from the merged tree and reverts
the setup_64.c part of fda262b897.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
The recent merge of fpu.S broken the handling of fpscr for
ARCH=powerpc and CONFIG_PPC64=y. FP registers could be corrupted,
leading to strange random application crashes.
The confusion arises, because the thread_struct has (and requires) a
64-bit area to save the fpscr, because we use load/store double
instructions to get it in to/out of the FPU. However, only the low
32-bits are actually used, so we want to treat it as a 32-bit quantity
when manipulating its bits to avoid extra load/stores on 32-bit. This
patch replaces the current definition with a structure of two 32-bit
quantities (pad and val), to clarify things as much as is possible.
The 'val' field is used when manipulating bits, the structure itself
is used when obtaining the address for loading/unloading the value
from the FPU.
While we're at it, consolidate the 4 (!) almost identical versions of
cvt_fd() and cvt_df() (arch/ppc/kernel/misc.S,
arch/ppc64/kernel/misc.S, arch/powerpc/kernel/misc_32.S,
arch/powerpc/kernel/misc_64.S) into a single version in fpu.S. The
new version takes a pointer to thread_struct and applies the correct
offset itself, rather than a pointer to the fpscr field itself, again
to avoid confusion as to which is the correct field to use.
Finally, this patch makes ARCH=ppc64 also use the consolidated fpu.S
code, which it previously did not.
Built for G5 (ARCH=ppc64 and ARCH=powerpc), 32-bit powermac (ARCH=ppc
and ARCH=powerpc) and Walnut (ARCH=ppc, CONFIG_MATH_EMULATION=y).
Booted on G5 (ARCH=powerpc) and things which previously fell over no
longer do.
Signed-off-by: David Gibson <dwg@au1.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This moves the remaining files in arch/ppc64/mm to arch/powerpc/mm,
and arranges that we use them when compiling with ARCH=ppc64.
Signed-off-by: Paul Mackerras <paulus@samba.org>
zImage.vmode was recently added. It's a version of zImage in which the ELF
note section used by open firmware indicates that it requires a virtual
mode instance of OF instead of real mode. This allows it to work with
Apple OF, and thus is directly bootable (or netbootable) from OF command
line. (Unfortunately, pSeries OF sort-of requires real mode and Apple OF
sort-of requires virtual mode, and both tend to be unhappy if no notes
section specifies the mode at all).
However, we forgot to add zImage.vmode to the default G5 build. This
fixes it.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
- merge common.c
- move model specific files
- remove stub Makefiles
- clean up arch/ppc*/Makefile
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This is less troublesome and makes more sense.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Now that asm-powerpc/* is using ifdefs on __powerpc64__ we need to add it
to CHECKFLAGS on ppc64.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The ppc and ppc64 trees are hopefully going to merge over time, so this
patch begins the process by creating a place for the merging of the
header files.
Create include/asm-powerpc (and move linkage.h into it from
asm-{ppc,ppc64} since we don't like empty directories). Modify the
ppc and ppc64 Makefiles to cope.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This adds the basic support for running on BPA machines.
So far, this is only the IBM workstation, and it will
not run on others without a little more generalization.
It should be possible to configure a kernel for any
combination of CONFIG_PPC_BPA with any of the other
multiplatform targets.
Signed-off-by: Arnd Bergmann <arndb@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The following kind of calls currently fails :
make ARCH=ppc64 CC="gcc-3.4"
Since the code for detecting a biarch compiler and adding the needed 64bit
magic argument fails if the AS/LD/CC commands are overriden in the command
line.
The attached patch fixes this by using the make override and += directive,
but i am not 100% sure this will work without gmake, as i am no Makefile
expert.
Cc: Paul Mackerras <paulus@samba.org>
Cc: Anton Blanchard <anton@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
gcc-4.0 generates altivec code implicitly when -mcpu indicates an
altivec capable CPU which is not suitable for the kernel. However, we
used to set -mcpu=970 when CONFIG_ALTIVEC was set because a gcc-3.x bug
prevented from using -maltivec along with -mcpu=power4, thus prevented
building the RAID6 altivec code.
This patch fixes all of this by testing for the gcc version. If 4.0 or
later, just normally use -mcpu=power4 and let the RAID6 code add
-maltivec to the few files it needs to be compiled with altivec support.
For 3.x, we still use -mcpu=970 to work around the above problem, which
is fine as 3.x will never implicitly generate altivec code.
The Makefile hackery may not be the most lovely, I welcome anybody more
skilled than me to improve it.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
