Over the past few weeks, I’ve focused on understanding and implementing a kernel driver for our system. In our original schedule, this task was supposed to take around a week. That has turned out not to be the case due to me running a bit behind and complications with the implementation of the kernel driver.
What I do have, is a user space front end to the controller kernel driver and a kernel space driver file that has not been compiled yet. Theoretically, this should work fine, but I have been unable to compile the kernel module due to complications with building against the pre-built kernel provided by Terasic. As far as I can tell, they do not provide the tools necessary to build against the provided kernel, and so a new one must be built from scratch and supplied to our board. I’ve begun this process, and hope to have the kernel built and booting by the end of today. If all goes well, I’ll be able to jump straight into testing the controller module tonight/tomorrow.
Due to the excessive and frustrating amount of time it has taken to write my first kernel module, audio has been pushed back to the body of this coming week. I don’t anticipate audio taking much time, as Joseph has a firm understanding of what would be the hardest part (communication with DDR3 and the cpu). Aside from this, it will be a relatively simple FSM that reads from memory and sends data to I2C. I believe the driver will be simple as well, considering I’ve learned some useful tools while reading up for the controller driver (ex. I can create a device file and arrange it so that the write system call sends samples to the kernel driver).
Once audio has been finished, I’ll be working on the sprite engine.
Drafts of the user space and kernel space implementation of the controller driver are available here:
https://drive.google.com/file/d/1LZ3EGkWE5TbSmbO2-qg8U7c6oalinqTu/view?usp=sharing