Re: [ECOS] ecos platform porting

[Christoph Csebits <christoph dot csebits at frequentis dot com>]

Hi,

On Sun, Dec 16, 2001 at 07:56:08PM +0800, Liu Wensheng wrote:
> Hi,
> i want to port ecos to a MPC860 board, but it is not in the list of 
> boards supported by eCos, i want to know what work i have to do,
> how much workload will be? and will i have to change a lot of
> source code? 
> if anyone have such experience, and tell me something, i will be
> grateful.

first start reading the docs at
http://sources.redhat.com/ecos/docs-latest especially 
http://sources.redhat.com/ecos/docs-latest/porting/index.html

Memorize the "MPC860 PowerQUICC User's Manual" as well as
"The Programming Environments for 32-Bit Microprocessors"
(Green Book). :-)

You need some functionality to upload code to your board
and start it.  (load-go bootstrapper in Flash, JTAG loader, ...)

Use the CVS version (snapshot at
ftp://ftp.skynet.ie/cvs/ecos-latest.tar.gz )

copy an existing port (MBX would the right for you) with
renaming the files accordingly. 

adjust the memory layout for matching your board in
myboard/current/include/pkgconf/mlt_powerpc_*[h,ldi]

After having done the linking stuff right, the core should
starting execution at the entry point _start in
arch/current/src/vectors.S. An On-Chip-Debugger would be
useful, at least some leds would also help.

rewrite the hal_hardware_init macro in myboard/current/src/myboard.S
(memory initialization, Base/Option Registers, ...)

disable cache/MMU at the beginning
write a diagnostic serial device driver (quicc/current/src/quicc_smc1.c)
write a flash driver (if needed)
write a ethernet driver (if needed)

It is recommended that you do not changing the existing code.
Copy the parts you have to change (create new packages). Its
easier when updating to a newer version of eCos.

I did first porting RedBoot to my platform. After having this 
done you have an working HAL for your platform, and the step
for running eCos applications should be a small one.

These are not the complete steps to get it working - only that
i remember on monday morning, but it will give an overview what
to do.

good luck
christoph
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