If you specify the (e.g., RTL8382M switch, RTL8197F router, RTL8822CE Wi-Fi), I can provide more targeted open-source driver sources or public documentation.
For the popular
For IoT-focused chips (Ameba series), Realtek has a semi-public portal. realtek sdk download
If you simply search "Realtek SDK download" on Google, you might find yourself frustrated. You will likely land on Realtek’s consumer download page, which only offers generic drivers, not development kits. If you specify the (e
In the world of embedded systems, networking, and audio engineering, few names are as ubiquitous as Realtek. From the Wi-Fi chip in your laptop to the audio controller on your motherboard and the Ethernet controller in your router, Realtek semiconductor solutions power a massive segment of the global electronics market. You will likely land on Realtek’s consumer download
This is the official and recommended route.