The RK3188 is a quad core Cortex A9 processor from Rockchip. The reason why it is so popular has to do with its low $12 price tag. You can find a number of low cost computer running on this processor on amazon or newegg. Just search for RK3188.
The bad thing about this processor from designer perspective is - they can not leverage the advantage of this low cost processor, since, there is literally no documentation available about this processor. Rockchips sells like 50 millions of this processor is a year ( the figure may not be exact or may be exaggerated, but you get the idea), and Rockchip does not want to be bothered for some US designers asking tens of question when there potential demand for this chip may be only couple of thousands of pcs a year.
But there are some information available and the purpose of the this blog is to point to the resources available on the internet.
The first pointer is a pdf schematics available from site called Radxa. You can see this schematics here . Here is a block diagram of this board looks like this
RADXA is based in Shenzen China and has made a reference board available for $99. You may be able to purchase it here .
The RADXA board has the source code for the kernel, Android and the Linux. However, it does not has the source code for the bootloader. In theory, the boodloader is more likely derived from an open source and we should have the source code available. As of now, there is no source code for the boot loader. This should not severely hamper any software development task, since you do not touch boot loader, unless, you need to change the boot sequence etc. For example, you may want to eliminate the NAND flash and would like to boot it directly from the SD Card.
We hope that the bootloader should also be made public in future.
If you wish to have your own custom design, you may want to start with the RADXA schematics. We do not have the design file, but it should not be a difficult task. Reference Designer has developed its own Orcad schematics for RK3188 and you may contact Reference Designer for the same. The datasheets of the processor is not available. Reference Designer is working on the layout. Please contact us if this is something of your interest.