Commit graph

7 commits

Author SHA1 Message Date
Andre Przywara
cdaa633fcf arm/arm64: implement a boot header capability
Some SPL loaders (like Allwinner's boot0, and Broadcom's boot0)
require a header before the actual U-Boot binary to both check its
validity and to find other data to load. Sometimes this header may
only be a few bytes of information, and sometimes this might simply
be space that needs to be reserved for a post-processing tool.

Introduce a config option to allow assembler preprocessor commands
to be inserted into the code at the appropriate location; typical
assembler preprocessor commands might be:
  .space 1000
  .word 0x12345678

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Steve Rae <srae@broadcom.com>
Commit Notes:
Please note that the current code:
  start.S (arm64) and
  vectors.S (arm)
already jumps over some portion of data already, so this option basically
just increases the size of this region (and the resulting binary).

For use with Allwinner's boot0 blob there is a tool called boot0img[1],
which fills the header to allow booting A64 based boards.
For the Pine64 we need a 1536 byte header (including the branch
instruction) at the moment, so we add this to the defconfig.

[1] https://github.com/apritzel/pine64/tree/master/tools
END
Reviewed-by: Tom Rini <trini@konsulko.com>
2016-06-06 13:39:19 -04:00
Georges Savoundararadj
c57a642384 arm: make .vectors section allocatable
A regression was introduced in commit 41623c91. The consequence of that
is the non-relocation of the section .vectors symbols :
_undefined_instruction, _software_interrupt, _prefetch_abort,
_data_abort, _not_used, _irq and _fiq.

Before commit 41623c91, the exception vectors were in a .text section.
The .text section has the attributes allocatable and executable [1].

In commit 41623c91, a specific section is created, called .vectors, with
the attribute executable only.

What have changed between commit 41623c91^ and 41623c91 is the attribute
of the section which contains the exception vectors.
An allocatable section is "a section [that] occupies memory during
process execution" [1] which is the case of the section .vectors.
Adding the lacking attribute (SHF_ALLOC or "a") for the definition of
the section .vectors fixed the issue.

To summarize, the fix has to mark .vectors as allocatable because the
exception vectors reside in "memory during execution" and they need to
be relocated.

[1] http://man7.org/linux/man-pages/man5/elf.5.html

Signed-off-by: Georges Savoundararadj <savoundg@gmail.com>
Acked-by: Albert ARIBAUD <albert.u.boot@aribaud.net>
2014-10-29 09:02:17 -04:00
Benoît Thébaudeau
a7f99bf139 arm: Fix _start for CONFIG_SYS_DV_NOR_BOOT_CFG
The boards using CONFIG_SYS_DV_NOR_BOOT_CFG (i.e. calimain,
da850evm_direct_nor and enbw_cmc) had the _start symbol defined after
the CONFIG_SYS_DV_NOR_BOOT_CFG word rather than before it in
arch/arm/lib/vectors.S. Because of that, if by lack of luck
'gd->mon_len = (ulong)&__bss_end - (ulong)_start' (see setup_mon_len())
was a multiple of 4 kiB (see reserve_uboot()), then the last BSS word
overlapped the first word of the following reserved RAM area (or went
beyond the top of RAM without such an area) after relocation because
__image_copy_start did not match _start (see relocate_code()).

This was broken by commit 41623c9 'arm: move exception handling out of
start.S files', which defined _start twice (before and after the
CONFIG_SYS_DV_NOR_BOOT_CFG word), then by commit 0a26e1d 'arm: fix a
double-definition error of _start symbol', which kept the definition of
the _start symbol after the CONFIG_SYS_DV_NOR_BOOT_CFG word. This new
commit fixes this issue by restoring the original behavior, i.e. by
defining the _start symbol before the CONFIG_SYS_DV_NOR_BOOT_CFG word.

Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau.dev@gmail.com>
Cc: Albert Aribaud <albert.u.boot@aribaud.net>
Cc: Manfred Rudigier <manfred.rudigier@omicron.at>
Cc: Christian Riesch <christian.riesch@omicron.at>
Cc: Sudhakar Rajashekhara <sudhakar.raj@ti.com>
Cc: Heiko Schocher <hs@denx.de>
2014-09-11 18:04:39 +02:00
Benoît Thébaudeau
58f9e1ae63 arm: Make reset position-independent
Some boards, like mx31pdk and tx25, require the beginning of the SPL
code to be position-independent. For these two boards, this is because
they use the i.MX external NAND boot, which starts by executing the
first NAND Flash page from the NFC page buffer. The SPL then needs to
copy itself to its actual link address in order to free the NFC page
buffer and use it to load the non-SPL image from Flash before running
it. This means that the SPL runtime address differs from its link
address between the reset and the initial copy performed by
board_init_f(), so this part of the SPL binary must be
position-independent.

This requirement was broken by commit 41623c9 'arm: move exception
handling out of start.S files', which used an absolute address to branch
to the reset routine. This new commit restores the original behavior,
which just performed a relative branch. This fixes the boot of mx31pdk
and tx25.

Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau.dev@gmail.com>
Reported-by: Helmut Raiger <helmut.raiger@hale.at>
Cc: Albert Aribaud <albert.u.boot@aribaud.net>
Cc: Magnus Lilja <lilja.magnus@gmail.com>
Cc: John Rigby <jcrigby@gmail.com>
Tested-by: Magnus Lilja <lilja.magnus@gmail.com>
2014-09-11 18:04:34 +02:00
Christian Riesch
db993fc8ec arm: include config.h in arch/arm/lib/vectors.S
config.h is required for CONFIG_SYS_DV_NOR_BOOT_CFG.

Signed-off-by: Christian Riesch <christian.riesch@omicron.at>
Reported-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Cc: Albert Aribaud <albert.u.boot@aribaud.net>
Cc: Masahiro Yamada <yamada.m@jp.panasonic.com>
Cc: Heiko Schocher <hs@denx.de>
Cc: Sudhakar Rajashekhara <sudhakar.raj@ti.com>
2014-08-29 15:50:43 -04:00
Masahiro Yamada
0a26e1d6c3 arm: fix a double-definition error of _start symbol
The symbol "_start" is defined twice in arch/arm/lib/vectors.S:
around line 48 and line 54.

If CONFIG_SYS_DV_NOR_BOOT_CFG is defined (as on calimain board),
build fails:

  arch/arm/lib/vectors.S: Assembler messages:
  arch/arm/lib/vectors.S:54: Error: symbol `_start' is already defined
  make[1]: *** [arch/arm/lib/vectors.o] Error 1
  make: *** [arch/arm/lib] Error 2

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Cc: Albert ARIBAUD <albert.u.boot@aribaud.net>
2014-06-09 10:36:40 +02:00
Albert ARIBAUD
41623c91b0 arm: move exception handling out of start.S files
Exception handling is basically identical for all ARM targets.
Factorize it out of the various start.S files and into a
single vectors.S file, and adjust linker scripts accordingly.

Signed-off-by: Albert ARIBAUD <albert.u.boot@aribaud.net>
2014-05-15 16:24:53 +02:00