[U-Boot-Users] REB1100: new board ?
aneganov at mail.ru
Sun Apr 6 23:35:10 CEST 2003
Below is the copy of my message posted yesterday to
arm-linux mailing list. I didn't get a reply yet but
I believe this list is better choice :)
Recently I bought ebook reading device called REB1100
(www.rca.com). It is built on ARM720T microprocessor,
has 64Kb of Atmel 27LV512 EPROM with romfs (bios), 8Mb of
NAND flash, Cirrus Logic EP7212 chip with LCD
controller and audio. Also it has modem, SMC
interface, IR interface and... cool rubber surface :)
Now the question. Is it somehow possible to
install [arm/uc]linux there? I study related
materials on armlinx website, on uclinux.org,
ucdot and some others but yet can't realize
from what to start.
Here are results of my "investigations".
First, this CPU has MMU so I can't decide what do I
need: uClinux or ARM linux :) [What was confused me -
uClinux is for non-MMU machines, but there are patches
for ARM7DMI CPU]
When REB1100 starts it executes code from EPROM. The
program there implementing simple filesystem, has USB
driver and some logic which allow it to install and
run 'firmware' (OS, Reader): it is possible to do all
this in special DEBUG mode with a tool called "rebhack".
Lets call it BIOS.
The firmware is on NAND Flash. As I understand, BIOS
do some checks and then runs [or not runs if checks
are failed] the OS.
Firmware has extension .rff and is compressed. It has
512 bytes header which contains some control and
descriptive fields, among them there is Execution
Address. It points to exactly 1Mb.
I hope it is possible to install Linux onto NAND
Flash without changing EPROM. I believe, to do that,
it is enough to make special .rff which contains boot
I have images of OS and BIOS but can't find
disassembler for ARM7 CPU (can you recommend
one? Is there a modification of objdump for ARM?)
An hour ago I've got the sources of U-Boot and read
README file on top level. From there I realized two
1) To get U-Boot image I have to start a new board.
2) U-Boot is installed into ROM, so I'll need to
re-burn EPROM. It is not really a problem for me,
but as I said above, I would be happy not to touch it
and do all the stff in NAND Samsung Flash.
I look forward to your answers.
Artiom mailto:aneganov at mail.ru
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