AMD Radeon RX 6700XT (RDNA2) on SiFive Unmatched
Computer Scientists patches Linux kernel to add AMD’s latest desktop GPU support.
René Rebe managed to add Radeon RX 6700 XT (Navi 22/Navy Flounder) support to the Linux kernel for its HiFive Unmatched development board.
HiFive Unmatched is a PC form factor development board powered by SiFive Freedom U740 multi-core processor. This processor is based on RISC-V architecture, an open-source alternative to ARM.
With a bit of work, Rebe was able to unlock high-performance graphics support on RISC-V architecture, which is the first time this was accomplished. He attached MSI Radeon RX 6700 XT Ventus GPU through PCIe Express raiser directly to the HiFive motherboard, which is essentially a tiny 17x17cm motherboard equipped with SiFive Freedom U740 SoC with 4 x U74 and 1x S7 cores. The motherboard is equipped with up to 16GB DDR4 memory and offers a PCIe Gen3 x8 interface.
He demonstrated hardware accelerated video encoding using RX 6700 XT graphics card, but the performance was clearly limited by the low-power U740 processor.
While this proof of concept is indeed a big milestone for RISC-V architecture, it is very far away from being widely available for consumers. The HiFive platforms are not meant for gamers, but software developers, Linux researchers, and hackers. Not to mention a very high price of this board going for around 700 USD.