Commit graph

18 commits

Author SHA1 Message Date
Gabe Black
36b2409a3d x86: Wrap small helper functions from libgcc to avoid an ABI mismatch
When gcc compiles some 64 bit operations on a 32 bit machine, it generates
calls to small functions instead of instructions which do the job directly.
Those functions are defined in libgcc and transparently provide whatever
functionality was necessary. Unfortunately, u-boot can be built with a
non-standard ABI when libgcc isn't. More specifically, u-boot uses
-mregparm. When the u-boot and libgcc are linked together, very confusing
bugs can crop up, for instance seemingly normal integer division or modulus
getting the wrong answer or even raising a spurious divide by zero
exception.

This change borrows (steals) a technique and some code from coreboot which
solves this problem by creating wrappers which translate the calling
convention when calling the functions in libgcc. Unfortunately that means
that these instructions which had already been turned into functions have
even more overhead, but more importantly it makes them work properly.

To find all of the functions that needed wrapping, u-boot was compiled
without linking in libgcc. All the symbols the linker complained were
undefined were presumed to be the symbols that are needed from libgcc.
These were a subset of the symbols covered by the coreboot code, so it was
used unmodified.

To prevent symbols which are provided by libgcc but not currently wrapped
(or even known about) from being silently linked against by code generated
by libgcc, a new copy of libgcc is created where all the symbols are
prefixed with __normal_. Without being purposefully wrapped, these symbols
will cause linker errors instead of silently introducing very subtle,
confusing bugs.

Another approach would be to whitelist symbols from libgcc and strip out
all the others. The problem with this approach is that it requires the
white listed symbols to be specified three times, once for objcopy, once so
the linker inserts the wrapped, and once to generate the wrapper itself,
while this implementation needs it to be listed only twice. There isn't
much tangible difference in what each approach produces, so this one was
preferred.

Signed-off-by: Gabe Black <gabeblack@chromium.org>
2011-11-29 21:31:24 +11:00
Gabe Black
dbaef6ef33 x86: Import the glibc memset implementation
The new implementation is about twice as fast as the old. This is from
glibc-2.14, sysdeps/i386/memset.c.

Signed-off-by: Gabe Black <gabeblack@chromium.org>
2011-11-29 21:31:17 +11:00
Gabe Black
60a9b6bfdd x86: Fix a few recently added bugs
Signed-off-by: Gabe Black <gabeblack@chromium.org>
Signed-off-by: Graeme Russ <graeme.russ@gmail.com>
2011-11-29 21:30:51 +11:00
Gabe Black
769db03a4a x86: Don't relocate symbols which point to things that aren't relocated
This change adds an upper bound for symbols which are fixed up after u-boot
is relocated into RAM. This way portions that are left at their original
location can be referred to without having to manually fix up any pointers.

Signed-off-by: Gabe Black <gabeblack@chromium.org>
2011-11-29 21:30:44 +11:00
Gabe Black
03228b26d5 x86: Fix how the location of the realmode and bios blobs are calculated
There are two blobs embedded into the u-boot image which are linked to run
at an address which is different from where they actually end up in the
ROM, one called "realmode" and one called "bios". There are realmode_setup
and bios_setup functions which prepare those blobs by copying them into the
location they're supposed to run from, among other things.

During u-boot relocation from ROM to RAM, the text and a few data segments
are copied over. The realmode and bios sections are not copied, and so the
only place they can be read from is their original location in the ROM.
Looking specifically at the bios blob, there are symbols defined in the
linker script called __bios_start and __bios_size which are defined to be
the start and size of the blob in the ROM.

In the bios_setup function, there seem to be two mistakes happening. First,
the offset from ROM to RAM is being added to __bios_start which implies that
this code expects to use the copy moved to RAM. No such copy is made, so
that's wrong. More subtly, when u-boot relocates itself, it goes through
all of the relocations stored in .rel.dyn and fixes them up. This has the
effect of transforming the __bios_start reference in bios_setup so that it
refers to the version in RAM (if one existed) instead of the one in ROM. To
correct for that, the offset actually needs to be subtracted out again to
translate the address back into the ROM.

The net effect is that for both blobs, a + needs to be changed to a -.

Signed-off-by: Gabe Black <gabeblack@chromium.org>
2011-11-29 21:30:38 +11:00
Graeme Russ
1cfcf03701 x86: Misc PCI touchups
Signed-off-by: Graeme Russ <graeme.russ@gmail.com>
2011-11-29 21:10:08 +11:00
Graeme Russ
303418cc97 x86: Ensure IDT and GDT remain 16-byte aligned post relocation
Some CPUs have strict alignment requirements for these tables

Signed-off-by: Graeme Russ <graeme.russ@gmail.com>
2011-11-29 21:10:01 +11:00
Graeme Russ
a76fc70ee1 x86: Provide more configuration granularity
Planned future ports requires more granularity for some options

Signed-off-by: Graeme Russ <graeme.russ@gmail.com>
2011-11-29 21:09:52 +11:00
Graeme Russ
83088afbba cosmetic: checkpatch cleanup of arch/x86/lib/*.c
Signed-off-by: Graeme Russ <graeme.russ@gmail.com>
2011-11-29 21:03:43 +11:00
Gabe Black
4c1c355a68 x86: Fix a compiler warning in arch/x86/lib/realmode.c
Ensure that the value being passed to a %d format specifier is of type
int.

Signed-off-by: Gabe Black <gabeblack@chromium.org>
2011-11-02 21:45:38 +11:00
Graeme Russ
3c7db1beac x86: Rename include/asm/ic to include/asm/arch-sc520
Also include some trivial related cleanups
2011-11-02 20:49:17 +11:00
Simon Glass
f5ca20c6b6 x86: Use getenv_ulong() in place of getenv(), strtoul
This changes the board code to use the new getenv_ulong() function.

Signed-off-by: Simon Glass <sjg@chromium.org>
2011-10-23 23:34:19 +02:00
Mike Frysinger
e2a53458a7 net: drop !NET_MULTI code
This is long over due.  All but two net drivers have been converted, but
those have now been dropped.

The only thing left to do is actually delete all references to NET_MULTI
and code that is compiled when that is not defined.  So here we scrub the
core code.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2011-10-05 22:22:16 +02:00
Albert ARIBAUD
fa82f871c8 Convert ISO-8859 files to UTF-8
There was a mix of UTF-8 and ISO-8859 files in the U-Boot source
tree, which could cause issues with the patchwork review system.
This commit converts all ISO-8859 files to UTF-8.

Signed-off-by: Albert ARIBAUD <albert.u.boot@aribaud.net>
2011-08-04 23:34:02 +02:00
Andreas Bießmann
09c2e90c11 unify version_string
This patch removes the architecture specific implementation of
version_string where possible. Some architectures use a special place
and therefore we provide U_BOOT_VERSION_STRING definition and a common
weak symbol version_string.

Signed-off-by: Andreas Biemann <andreas.devel@googlemail.com>
CC: Mike Frysinger <vapier@gentoo.org>
CC: Peter Pan <pppeterpppan@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
2011-07-28 17:22:53 +02:00
Graeme Russ
4769be21cc Timer: Remove reset_timer() for non-Nios2 arches 2011-07-26 14:53:30 +02:00
Graeme Russ
5c8404aff1 Timer: Remove set_timer completely 2011-07-26 14:52:17 +02:00
Graeme Russ
fea2572001 x86: Rename i386 to x86
Signed-off-by: Graeme Russ <graeme.russ@gmail.com>
2011-04-13 19:43:28 +10:00