[U-Boot-Users] Generic ARM Error with respect to usage of r8 in start.S's.
wd at denx.de
Tue Jun 24 22:28:31 CEST 2003
In message <FD2AC9A020DDD51194710008C7089B20053D4CAD at dlee17.itg.ti.com> you wrote:
> The u-boot for ARM code defines and uses global data which is not referenced
> using r8 (can be seen by all). The code as currently generated only uses r8
> to access into the bd_info structure and its members. As it is, the bd_info
No. All access to the "global data pointer" ("*gd") goes through r8,
as defined in "include/asm-arm/global_data.h":
#define DECLARE_GLOBAL_DATA_PTR register gd_t *gd asm ("r8")
> structure is allocated on the C stack in start_armboot(), there is nothing
> special about the sdram which its allocated in. The structure could have as
As mentioned before, the ARM initialization sequence and memory map
do not exactly fit into the U-Boot model as it was intended to be.
The curerent state is a result of the port done for the ARMBoot
project, but this is a temporary state which will be fixed in a
> Yes the flexibility to do different things is there which is good,
> unfortunately the leaving of expansion hooks which break the existing code
> somewhat defeats its usefulness.
The problem is that we obviously missed the exception code when
chosing r8. If you can, please submit a patch to fix this problem.
Software Engineering: Embedded and Realtime Systems, Embedded Linux
Phone: (+49)-8142-4596-87 Fax: (+49)-8142-4596-88 Email: wd at denx.de
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