A lot of pins are secondary functions on the Bay Trail SOC and thus not available at power on. These pins defaults to function 0 which is either not connected, other function or GPIO pin. They can be configured through configuration registers for each multiplex pad.
The documentation for the DDI signals is completely missing from the documentation.
The DDI signals that are multiplexed and thus not present at the SOC pad are:
Furthermore LPC signals, speaker signal, serial IRQ and a lot of other critical signals are also multiplexed and not the default functions at power on. If you don't configure these signals, most of the functionality that signifies a PC is missing.
However, the DDI signals can not be configured as there are no documentation what so ever of the offset off these configuration register, nor their contents.
What about the rest of these signals? Well, they are documented, but they are locked from configuration and need to be unlocked by some other configuration registers. And guess what, these are not documented!
So you have BIOS writer guides, external device specifications and yet there is impossible to do anything as there are crucial missing peaces.
Yes, I'm kind of frustrated as Intel do state of the art magic hardware which deserves state of the art software. But doing state of art software is impossible if vital parts are left out of the documentation.
I posted this question earlier and it marked as answered. I didn't get any answer. In fact I have tried to get answers from Intel in five years without success. And I don't ask for much, just proper documentation. I'm a wizard on the X86 and just wish to interact with the hardware. Is that too much to ask? If you got the assignment to contact a person, but they do not exist in any record and you don't have the phone number, what should you do? Try all possible combinations of phone numbers?
I have been in the lab everyday during the entire Christmas, weekends and New Years Eve and today. So I'm sorry, I'm a bit frustrated and disappointed of the lack of support!
Hello, B-O. Sorry for the delay as we have been on holiday. On Monday, I will get your request into the system and alert the Intel representative to assist you.
They may at that time involve another representative who covers your customer's account as well. LynnZ.
Also see thread /message/10740# 10740 https://embedded.communities.intel.com/message/10740# 10740