RISC-V is an architecture instruction set (ISA) open source based on the reduced instruction set concept (RISC). It has 32, 64 and 128 bit variants, along with its open specifications that has sparked great interest in building mobile devices.
For its part, Android is an OS adaptable to various architectures and devices, this due to its "open source" nature. Even At the time Google expressed its "love" for RISC-V during the “RISC-V Summit 2022” held in December and mentioned its intentions to officially support the architecture on Android.
Nonetheless, It seems that that only remained in words, or at least that's what Google has shown with the recent patches removing RISC-V support ACK (Android Common Kernel) supports the RISC-V kernel, the RISC-V kernel build, and the RISC-V emulator. This decision has generated divided opinions, but for the most part, it is criticism that has rained down on Google.
Tal and as Android Authority explains: ACK is the basis of the kernel of all Android products and also provides a unified kernel foundation for AOSP. Simply put, ACK is a fork of Google's upstream Linux kernel, but with Android-specific additions added that haven't yet been merged into the mainline or Long Term Support (LTS) kernel.
There are several branches of ACK, including android-mainline, which is the main development branch that branches into kernel branches «GKI» (kernel overview), a project launched by Google to solve the problem of kernel fragmentation by unifying.
The GKI kernel provides a stable kernel module interface (KMI) for kernel modules, so that the module and the kernel can be updated independently. Each certified Android device will ship with a kernel based on one of these GKI branches, as Google does not currently certify Android devices built with the mainline Linux kernel.
With this, basicallyThe next version of Android that uses the latest version of GKI will not be compatible with devices that have chips RISC-V. As a result, companies wishing to create a version of Android for RISC-V devices will need to develop and maintain their own version of the Linux kernel using RISC-V ACK patches.
However, This merged patch is not permanent, as Google has not removed forever compatibility with RISC-V, and Google has not remained silent and has mentioned that its commitment to RISC-V is real and despite the controversy generated by the recent patches, Google has assured that it continues to support the RISC-V architecture on Android.
The company snotes that, due to the speed of the iterations, adjustments have been made in the generic Android kernel image (GKI), so the move made does not mean an abandonment of its efforts in adopting RISC-V.
To ensure compatibility Android with RISC-V, Google works in collaboration with the community and the RISE project (RISC-V Software Ecosystem), this with the purpose of accelerating the availability of software for high-performance, low-power RISC-V processors and not only for Android, but also for Linux and other operating systems in various application areas, such as high performance computing.
Finally, it should be mentioned that Google has not provided details about the reason behind the implementation of the patches, but it does confirm that RISC-V support on Android has not been completely removed, plus there is speculation that the move was prompted by government policies aimed at curbing the growth of device manufacturing. chips in China and that the United States seeks to stop China from using the RISC-V architecture.
Although this is not entirely clear, at the moment with Google's decision and its commitment to not abandon compatibility it may mean that we will have to wait longer than expected before seeing commercial Android devices running with RISC-V chips.
Source: https://www.androidauthority.com