A few days ago Galland contacted me saying that he found this github repository containing new Rockchip kernel sources that referenced the new quad core RK3188 SOC.
The original source of this repo is once again bq Readers, the Spanish tablet maker that was among the first manufacturers to release the RK3066 kernel code last year. The original kernel source is meant for the bq Curie model, and can be found here.
Looking at the bq Curie kernel snapshot it is version 3.0.36+ of the linux kernel, like all the RK3188 devices currently use. The code is the most up-to-date Rockchip version that I've seen so far. I started out to configure the kernel for the MK808B because I was curious to know whether or not this kernel snapshot has support for the RK903 Wifi/Bluetooth working out-of-the-box. Since the HDMI drivers are also updated from the version I use it might as well have fixes for the "Black screen/No signal" problem as seen in the 3.0.8+ version of the kernel. I decided to leave all code as-is and see if it compiled to begin with. I had to make a couple of changes in order to get the kernel compiled, and after it finally compiled I had to fiddle with the kernel configuration here and there because of some errors I made in the configuration.
The kernel booted but Android didn't start, so I had to check what happened using the serial console. Problem was that the serial console got disabled early in the boot process, so I couldn't see what went wrong. Current status is that I have the serial console fixed. I now know that Android is not booting because of the missing/non-working NAND module for the 3.0.36+ kernel. I tried changing the kernel version back to 3.0.8+ but then the NAND module crashes. So next thing will be to copy over the 3.0.36+ version from the Cube or the MK908 to see if that works.
Looking at the code a bit further one sweet thing I found was that it finally contains source code for clock_data.c. I broke my head over this previously closed source part over and over again. I need to investigate this piece of code later, since this might open up more overclock/underclock possibilities. But more importantly it can drastically improve general stability if tweaked correctly.
Hopefully I will find some time later this week to see if this kernel snapshot can be used on the RK3188 quad core MK908 device. If this version of the kernel indeed is usable for the RK3188 quad cores, then a big thank you goes out to bq Readers for providing the code. This sets an example for other companies that up until now refuse to follow the (GPL license) rules!
A lot of developments... Nice!
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