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>
By adding a multiboot header, U-Boot can be loaded by GRUB2. Using GRUB2 to
bootstrap U-Boot is useful for using an existing BIOS to get an initial
U-Boot port up and running before implementing the low-level reset vector
code, SDRAM init, etc. and overwriting the BIOS
Signed-off-by: Graeme Russ <graeme.russ@gmail.com>
U-Boot Makefiles contain a number of tests for compiler features etc.
which so far are executed again and again. On some architectures
(especially ARM) this results in a large number of calls to gcc.
This patch makes sure to run such tests only once, thus largely
reducing the number of "execve" system calls.
Example: number of "execve" system calls for building the "P2020DS"
(Power Architecture) and "qong" (ARM) boards, measured as:
-> strace -f -e trace=execve -o /tmp/foo ./MAKEALL <board>
-> grep execve /tmp/foo | wc -l
Before: After: Reduction:
==================================
P2020DS 20555 15205 -26%
qong 31692 14490 -54%
As a result, built times are significantly reduced, typically by
30...50%.
Signed-off-by: Wolfgang Denk <wd@denx.de>
Cc: Andy Fleming <afleming@gmail.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Albert Aribaud <albert.aribaud@free.fr>
cc: Graeme Russ <graeme.russ@gmail.com>
cc: Mike Frysinger <vapier@gentoo.org>
Tested-by: Graeme Russ <graeme.russ@gmail.com>
Tested-by: Matthias Weisser <weisserm@arcor.de>
Tested-by: Sanjeev Premi <premi@ti.com>
Tested-by: Simon Glass <sjg@chromium.org>
Tested-by: Macpaul Lin <macpaul@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.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>
This pushes the ugly duplicated arch ifdef lists we maintain in various
image related files out to the arch headers themselves.
Acked-by: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
Tested-by: Thomas Chou <thomas@wytron.com.tw>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Allow redirection of console output prior to console initialisation to a
temporary buffer.
To enable this functionality, the board (or arch) must define:
- CONFIG_PRE_CONSOLE_BUFFER - Enable pre-console buffer
- CONFIG_PRE_CON_BUF_ADDR - Base address of pre-console buffer
- CONFIG_PRE_CON_BUF_SZ - Size of pre-console buffer (in bytes)
The pre-console buffer will buffer the last CONFIG_PRE_CON_BUF_SZ bytes
Any earlier characters are silently dropped.
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>
Clean up some duplicated prototype declarations.
Get rid of now useless AVR32 initcalls.h file.
Signed-off-by: Wolfgang Denk <wd@denx.de>
Cc: Albert Aribaud <albert.aribaud@free.fr>
Cc: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Cc: Graeme Russ <graeme.russ@gmail.com>
Recieve/Receive
recieve/receive
Interupt/Interrupt
interupt/interrupt
Addres/Address
addres/address
Signed-off-by: Mike Williams <mike@mikebwilliams.com>
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>
Currently, some linker scripts are found by common code in config.mk.
Some are found using CONFIG_SYS_LDSCRIPT, but the code for that is
sometimes in arch config.mk and sometimes in board config.mk. Some
are found using an arch-specific rule for looking in CPUDIR, etc.
Further, the powerpc config.mk rule relied on CONFIG_NAND_SPL
when it really wanted CONFIG_NAND_U_BOOT -- which covered up the fact
that not all NAND_U_BOOT builds actually wanted CPUDIR/u-boot-nand.lds.
Replace all of this -- except for a handful of boards that are actually
selecting a linker script in a unique way -- with centralized ldscript
finding.
If board code specifies LDSCRIPT, that will be used.
Otherwise, if CONFIG_SYS_LDSCRIPT is specified, that will be used.
If neither of these are specified, then the central config.mk will
check for the existence of the following, in order:
$(TOPDIR)/board/$(BOARDDIR)/u-boot-nand.lds (only if CONFIG_NAND_U_BOOT)
$(TOPDIR)/$(CPUDIR)/u-boot-nand.lds (only if CONFIG_NAND_U_BOOT)
$(TOPDIR)/board/$(BOARDDIR)/u-boot.lds
$(TOPDIR)/$(CPUDIR)/u-boot.lds
Some boards (sc3, cm5200, munices) provided their own u-boot.lds that
were dead code, because they were overridden by a CPUDIR u-boot.lds under
the old powerpc rules. These boards' own u-boot.lds have bitrotted and
no longer work -- these lds files have been removed.
Signed-off-by: Scott Wood <scottwood@freescale.com>
Tested-by: Graeme Russ <graeme.russ@gmail.com>
Partial linking allows weak functions to be overridden in files containing
only one function. Moving the sc520 override of reset_cpu gets rid of an
ugly #ifdef
Signed-off-by: Graeme Russ <graeme.russ@gmail.com>
Gabe Black
Gabe Black
Graeme Russ
Wolfgang Denk
Ondrej Kupka
Simon Glass
Anton Staaf
Mike Frysinger
Albert ARIBAUD
Mike Williams
Andreas Bießmann
Scott Wood