Use the base address of the 'F' segment as a pointer to the global data
structure. By adding the linear address (i.e. the 'D' segment address) as
the first word of the global data structure, the address of the global data
relative to the 'D' segment can be found simply, for example, by:
fs movl 0, %eax
This makes the gd 'pointer' writable prior to relocation (by reloading the
Global Desctriptor Table) which brings x86 into line with all other arches
NOTE: Writing to the gd 'pointer' is expensive (but we only do it
twice) but using it to access global data members (read and write) is
still fairly cheap
--
Changes for v2:
- Rebased against changes made to patch #3
- Removed extra indent
- Tweaked commit message
This commit introduces no functional changes - It simply re-arranges the
calculations so that adding to them in future commits will be cleaner
--
Changes for v2:
- Fixed typo in title
- Added commit message
Move the relocation offset calculation out of assembler and into C. This
also paves the way for the upcoming init sequence simplification by adding
the board_init_f_r flash to RAM transitional function
--
Changes for v2:
- Added commit message
- Minor adjustment to new stack address comment
The implementations of memcpy and memset are now the optimised versions
from glibc, so use them instead of simple copy loops
--
Changes for v2:
- Removed unneeded brackets
This change finishes plumbing the initrd support built into the zboot
mechanism out to the command interface.
It also fixes a bug in the command declaration where the kernel size could
be passed as an optional second parameter but not enough arguments were
allowed.
Signed-off-by: Gabe Black <gabeblack@chromium.org>
If vboot successfully verifies a kernel, it will leave it in place and
basically ready to boot. The zeropage table which is part of the x86 boot
protocol is at the end of the kernel, though, instead of the beginning, and
because the image is already in place there's no need to copy it around.
This change refactors the code which implements the zboot command so that
the configuration of the zeropage table and loading the pieces of the
kernel into memory are done separately. Also, because the command line goes
before the zeropage table in vboot which is somewhat incompatible with the
normal protocol, where to put the command line is a now a parameter instead
of being hard coded.
Signed-off-by: Gabe Black <gabeblack@chromium.org>
This change conditionally modifies the zboot command so that it can use the
32 bit boot protocol. This is necessary because the 16 bit realmode entry
point assumes that it can call BIOS services which neither coreboot nor
u-boot provide.
Signed-off-by: Gabe Black <gabeblack@chromium.org>
This change cleans up some formatting issues in the zimage handling code, and
converts it from using offsets added to a base pointer to using the available
structure definitions which were already being included.
Signed-off-by: Gabe Black <gabeblack@chromium.org>
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>
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>
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>
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>
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>
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>
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>
