Hi Albert,
On Fri, Jul 4, 2014 at 10:35 PM, Albert ARIBAUD albert.u.boot@aribaud.net wrote:
Hi Christian,
On Wed, 2 Jul 2014 15:45:17 +0200, Christian Riesch christian.riesch@omicron.at wrote:
Hello Albert,
On Wed, Jun 18, 2014 at 2:55 PM, Christian Riesch christian.riesch@omicron.at wrote:
Am I missing something here? What would be the preferred solution to make the board working again?
Any comments on this? What shall we do to get the boards working again?
Sorry for the delay.
My opinion is that for these boards, there should actually be *no* exception vectors at the start of the image, since it would never serve any purpose anyway unless as you suggest we copy the vectors table from the image to the actual vectors table location (or set the VBAR to the image vector table location for those targets which allow it).
(and I don't think this is limited to the three boards discussed here. IOW, the current exception/interrupt system in ARM U-Boot is FUBAR.)
As far as fixing the boards, Masahiro had posted a series where one patch fixed the issue. I NAKed the submission for several reasons; I had expected a followup (v3) which I failed to ping for.
MAsahiro: do you have a v3 ready?
I assume you are talking about [1]. Adding this #include alone does not solve the issue for the calimain board.
With adding the include, we would end up with
#include <config.h>
#ifdef CONFIG_SYS_DV_NOR_BOOT_CFG .word CONFIG_SYS_DV_NOR_BOOT_CFG #endif _start:
ldr pc, _reset ...
in arch/arm/lib/vectors.S. As a result, __image_copy_start points to 0x60000000 (CONFIG_SYS_TEXT_BASE) and _start points is 0x60000004. The relocation code in arch/arm/lib/relocate.S calculates its relocation offset based on __image_copy_start. However, arch/arm/lib/board.c calculates the offset as
gd->reloc_off = addr - (ulong)&_start;
As the two are different, we have different offsets for the relocation code in relocate.S (based on __image_copy_start) and the calculation of the lr register in arch/arm/lib/crt0.S (gd->reloc_off). After relocation, the CPU jumps to the wrong address.
So we can either unify the offset calculation (which of the two is the correct one?) or put the _start label where it was in earlier versions of u-boot:
#include <config.h>
_start: #ifdef CONFIG_SYS_DV_NOR_BOOT_CFG .word CONFIG_SYS_DV_NOR_BOOT_CFG #endif
ldr pc, _reset ...
What do you think? Thanks, Christian
[1] http://lists.denx.de/pipermail/u-boot/2014-June/181334.html