diff options
| author | Mike Frysinger <vapier@gentoo.org> | 2008-10-11 21:40:26 -0400 |
|---|---|---|
| committer | Mike Frysinger <vapier@gentoo.org> | 2009-01-28 13:26:14 -0500 |
| commit | b5eba3fafcccd1979380f12a256bd0e19be3d61e (patch) | |
| tree | 703504cad609428edbd07d9d2ac64af56cf28916 /cpu/blackfin | |
| parent | 95433f6d43ede6b40c1d900f3f704c839aa074f1 (diff) | |
| download | u-boot-imx-b5eba3fafcccd1979380f12a256bd0e19be3d61e.zip u-boot-imx-b5eba3fafcccd1979380f12a256bd0e19be3d61e.tar.gz u-boot-imx-b5eba3fafcccd1979380f12a256bd0e19be3d61e.tar.bz2 | |
Blackfin: clarify relocation comment during init
People often ask questions about the init process and when things go
from flash to relocated base, so clarify the comments a bit.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Diffstat (limited to 'cpu/blackfin')
| -rw-r--r-- | cpu/blackfin/start.S | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/cpu/blackfin/start.S b/cpu/blackfin/start.S index 8617c98..6c8def4 100644 --- a/cpu/blackfin/start.S +++ b/cpu/blackfin/start.S @@ -125,9 +125,11 @@ ENTRY(_start) */ r6 = 1 (x); - /* Relocate from wherever are (FLASH/RAM/etc...) to the hardcoded + /* Relocate from wherever we are (FLASH/RAM/etc...) to the hardcoded * monitor location in the end of RAM. We know that memcpy() only - * uses registers, so it is safe to call here. + * uses registers, so it is safe to call here. Note that this only + * copies to external memory ... we do not start executing out of + * it yet (see "lower to 15" below). */ serial_early_puts("Relocate"); call _get_pc; @@ -172,7 +174,9 @@ ENTRY(_start) * setting the 15 handler to ".Lenable_nested", raising the 15 * interrupt, and then returning from the highest interrupt * level to the dummy "jump" until the interrupt controller - * services the pending 15 interrupt. + * services the pending 15 interrupt. If executing out of + * flash, these steps also changes the code flow from flash + * to external memory. */ serial_early_puts("Lower to 15"); r0 = r7; |