[U-Boot] [PATCH] env: allow people to force envcrc building

[Mike Frysinger]

On Sun, Apr 24, 2011 at 10:28 AM, Wolfgang Denk wrote:
> Mike Frysinger wrote:
>> For people who want to manually extract the embedded environment so that
>> it can be manually packed into the final u-boot image, add a config opt
>> to force building of the envcrc tool.
>>
>> Signed-off-by: Mike Frysinger <vapier at gentoo.org>
>> ---
>>  README                |    5 +++++
>>  common/env_embedded.c |    2 +-
>>  include/common.h      |    5 +++++
>>  tools/Makefile        |    1 +
>>  tools/envcrc.c        |   10 +++++++---
>>  5 files changed, 19 insertions(+), 4 deletions(-)
>
> How would that be used?  Can you please provide an example?

for Blackfin targets, i have to generate an LDR format.  this is the
file that is ultimately burned into the flash.  since i cant embed the
env in the original ELF/binary (since offsets in that will not
correlate to actual flash offsets), i have to let the ldr-utils do the
embedding.

so after the final ELF has been linked, Blackfin targets run:
tools/envcrc --binary > env-ldr.o
bfin-uclinux-ldr -T bf548-0.0 -c u-boot.ldr u-boot --bmode PARA
--use-vmas --initcode arch/blackfin/cpu/initcode.o  -J --punchit
$((0x2000)):$((0x2000)):env-ldr.o --dma 6

and this produces the LDR:
  DXE 1 at 0x00000000:
              Offset      BlockCode  Address    Bytes      Argument
    Block  1 0x00000000: 0xADC85006 0xFFA00000 0x00000000 0x00049CF4 (
16bit-dma-from-16bit ignore first )
    Block  2 0x00000010: 0xADAF0806 0xFFA00000 0x00000170 0xDEADBEEF (
16bit-dma-from-16bit init )
    Block  3 0x00000190: 0xAD340006 0x03F00000 0x00001E50 0xDEADBEEF (
16bit-dma-from-16bit )
    Block  4 0x00001FF0: 0xAD711006 0x00000000 0x00002000 0xBAADF00D (
16bit-dma-from-16bit ignore )
    Block  5 0x00004000: 0xADE50006 0x03F01E50 0x000061B0 0xDEADBEEF (
16bit-dma-from-16bit )
    .... more Blocks ....

and now the embedded environment is at the right offset -- 0x2000
(it's Block 4 in the above output)
-mike