Leave it to AMD to continue to add some last-minute coding before the merge window for Linux 5.20 opening next week, reports Michael Larabel of the website Phoronix. Typically, cutoffs for any feature work placed into the DRM-Next queue for each Linux kernel cycle ends near the "-rc6" point of the cycle. The closing window has yet to stop AMD from attempting to ensure any finalizing of drivers for the upcoming Linux 5.20 kernel for their upcoming RDNA 3 graphics architecture.
AMD continues to add additional support for their RDNA 3 architecture with the merge window closing soon
Larabel reports that AMD added some extra new features in a pull request posted to DRM-Next last Tuesday. With only a few days, not weeks, left until we reach the next merge period, there is minimal risk of any reversal. This low risk is because the alterations to AMDGPU coding are currently inserted into the new IP blocks present within Linux 5.20. AMD's latest hardware is to release in the coming months, and while it is not under the support of the current Linux 5.19 kernel, it is believed that the new additions to the driver will see inclusion before the next window.
New modifications for the RDNA 3 graphics driver for Linux 5.20 are
- fixes for VCN4 video codecs
- Reliability, Availability, and Serviceability (RAS) support for the UWB Multi-interface Controller (UMC), version 8.10
- Audio Co-Processor (ACP) support for the company's Jadeite platforms
- run-time power management fixes
- exposing additional GFXOFF data/statistics via DebugFS
- floating point code clean-ups around new Display Core Next (DCN) display blocks
- repairing DCN display code support for PowerPC
Breaking down each of the modifications for newer readers, The RAS support for the UMC 8.10 is speculated to be utilized by AMD Instinct MI300 chips. ACP support for AMD's Jadeite platform refers to AMD Radeon R4 integrated graphics adapter, also known as Stoney Ridge, and is considered a weaker mobile dual-core APU series. When Stoney Ridge first launched, the AMD A6-9210 utilized it starting in 2016. The low-level APU offered 192 shaders and processed as high as 600 MHz, depending on the TDP and system memory.
The PowerPC is a RISC microprocessor architecture that allows 64-bit and 32-bit implementations, where the 32-bit implementation is included in the 64-bit processes. GFXOFF is a feature of the graphics processor, allowing the graphics engine to be powered off in situations where it would be inactive while not processing any graphics workloads, achieving a level of power savings. The debugfs program is an interactive file system debugger used to review and modify the condition of an ext2, ext3, or ext4 file system.
Other features were added but were minor in detail and not mentioned to a greater extent.
Larabel notes that the recent pull request from AMD reveals IP version information to the user space for consumption by the user-mode drivers. Drivers affected would be the AMDVLK, RadeonSI Gallium3D, RADV, and ROCm codes. The IP version information added to the user space is crucial for enabling newer hardware devices and is a component of the new "block-by-block driver enablement approach." This enablement and previous IP block inclusion were the primary concern and heavily focused on the Linux 5.20 kernel.
The new Linux 5.20 kernel will be complete and active this October. It is unknown if the RDNA 3 GPU support in the upcoming kernel will be acceptable enough for full use or if users will need to wait until the complete release is ready, especially with the enablement from a block-by-block strategy is utilized in these situations.
Linux 5.20 will also be the minimum version requirement for Intel's Arc Graphics desktop GPUs.
Users can locate the pull request for the newest updates for AMDGPU in Linux 5.20 here.
News Sources: Phoronix, Linux Kernel info page
