u-boot-brain/cpu/arm920t/at91rm9200
David Brownell 06bffc6ea5 rm9200 lowevel_init: don't touch reserved/readonly registers
For some reason the AT91rm9200 lowlevel init writes to a bunch of
reserved or read-only addresses.  All the boards seem to define the
value-to-be-written values as zero ... but they shouldn't actually
be writing *anything* there.

No documented erratum justifies these accesses.  It looks like maybe
some pre-release BDI-2000 setup code has been carried along by cargo
cult programming since at least late 2004 (per GIT history).

Here's a patch disabling what seems to be bogosity.  Tested on a
csb337; there were no behavioral changes.

Signed-off-by: David Brownell <david-b@pacbell.net>

on RM9200ek
Tested-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
2009-08-03 09:26:26 +02:00
..
bcm5221.c cpu/[7a-ln-z]*: Remove obsolete references to CONFIG_COMMANDS 2007-07-09 18:57:22 -05:00
dm9161.c Add MACH_TYPE records for several AT91 boards. 2007-08-14 10:10:52 +01:00
ether.c rm9200 ethernet driver: board-specific quirk (csb337) 2009-07-22 22:39:23 -07:00
i2c.c i2c: Create common default i2c_[set|get]_bus_speed() functions 2009-06-12 20:39:45 +02:00
lowlevel_init.S rm9200 lowevel_init: don't touch reserved/readonly registers 2009-08-03 09:26:26 +02:00
lxt972.c Remove duplicate definitions in include/lxt971a.h. 2008-07-06 23:44:34 -07:00
Makefile arm: timer and interrupt init rework 2009-06-12 20:39:48 +02:00
reset.c at91rm9200: move reset code to reset.c 2009-06-12 20:39:48 +02:00
spi.c rename CFG_ macros to CONFIG_SYS 2008-10-18 21:54:03 +02:00
timer.c arm: timer and interrupt init rework 2009-06-12 20:39:48 +02:00
usb.c rename CFG_ macros to CONFIG_SYS 2008-10-18 21:54:03 +02:00