How to get further according to cr2 in XDA Developers. Questions, Answers and HowTo.
Q> Do I need to tell HaRET about my framebuffer address?
R> No. First, haret knows the address, but it's the Linux kernel business to deal with the hardware.
Q> Does the kernel need information about the video chipset?
R> Since your framebuffer address is not in RAM, the dedicated kernel video driver is needed (i.e. not PXA LCD driver), and it needs some information where the hardware is located.
Q> What is needed to make HaRET talk over the USB serial connection?
R> You need the USB kernel driver for that, and you don't need synce, but the usb tty driver (usbserial). For that you should know which USB chipset is used (with 99% probability it is PXA UDC).
What you should do is as follows:
0>. Describe you hardware : what does it have ?
MMC/SD/CF/PCMCIA ? RS232 cable ? USB ? IR ? Camera ? Wifi ? Bluetooth ? Ethernet ? etc.
1>. Can you open the device box ? If yes, make the motherboard and parts photos and make them available over internet.
2>. Run some WinCe programm that shows the serial ports, then we can guess what of them are used and how. (Using the PHM Device Manager for instance)
2a>. Dump the WinCe registry in the human-readable form.
3>. Split the rom and run '$strings' and '$strings -el' on the files, or just on the rom itself.
Dump your rom with HaRET and with itsutils (pmemdump) . Do they produce the same output ? itsutils download here : [You must be registered and logged in to see this link.]
Post the dumped first 8192 bytes (or a bit more) in XDA or to a forum where to get help.
5>. Now things become hard and should be handed over to the people who know better
Q> Trying a new kernel with the information about the video chip, of course without any booting result.
R> You need to feed the framebuffer address to the driver, because the video chip is memory mapped somewhere around it. If you have the documentation and a linux driver, so look there. It's also worth looking into the .data section of the WinCe video driver (if you have it), or somewhere in .text in between.
Make the gpio tracelogs with 'wgpio 60' and transfer something over IR, make a GSM call, call your PDA from another phone, etc.