AMD released over 200 Linux patches (opens in new tab) today for an unannounced graphics card (opens in new tab), as reported by Linux news outlet Phoronix (opens in new tab). The Radeon graphics card, codename Sienna Cichlid, is presumably the Big Navi (opens in new tab) that the hardware world has been eagerly anticipating.
Phoronix said that AMD developers have considered using a substitute codename to hide a product's real marketing name before. This makes sense, considering that developers have to release patches in advance, and using a fake name could help hide the product from prying eyes.
The Linux patch, which was signed off by Alex Deucher from AMD, explicitly states that "Sienna Cichlid is a GPU from AMD."
"This patch set adds support for it including power management, display, kfd, interrupts, gfx, multi-media,etc," the patch reads.
This is the first time that Sienna Cichlid has ever appeared in public. If it weren't for the description, no one would ever think that Sienna Cichlid is in anyway related to a graphics card. Sienna is a yellowish-brown substance from the earth, and cichlid is a fish. If you put both together, you get a yellowish-brown fish - a great way to mask a graphics card.
The Linux patches point to Sienna Cichlid's utilization of AMD's Video Core Next (VCN) 3.0 and Display Core Next (DCN) 3.0 engines. Existing Navi graphics card are on VCN 2.0 and DCN 2.0, so it'd be logical for the next wave of Navi products to transition to 3.0. The current gossip is that Sienna Cichlid might be using the Navi 21 silicon that's based on the RDNA 2 architecture. One particular patch (opens in new tab) hints to the usage of GDDR6 memory on the graphics card.
According to Phoronix, Sienna Cichlid won't be inserted until the Linux 5.9 merge window, which is expected for August. The stable version would consequently land in October.
That time frame suggests Sienna Cichlid could be an RDNA 2 graphics card coming later this year. A DigiTimes report last month claimed that AMD Big Navi's release (opens in new tab)date will be September. The rumored dates line up perfectly.
The latter makes more sense to me, but I did not research it.