On Mon, Sep 26, 2022 at 12:01:19PM +1000, Jonathan Gray wrote: > On Sun, Sep 25, 2022 at 05:28:29PM +0200, Mark Kettenis wrote: > > > From: Daniel Pocock <dan...@pocock.pro> > > > Date: Tue, 20 Sep 2022 11:45:50 +0200 > > > > > > After the feedback about amdgpu being unsupported on the big endian > > > OpenBSD build, I decided to try a radeondrm supported card, the Radeon > > > R9 290X ASUS DirectCU II 4GB. > > > > I fear that card is too new and doesn't work on big-endian platforms > > either. Hawaii is GCN 2, but even GCN 1 cards (Oland) don't work > > properly on big-endian machines. I don't really know at what hardware > > generation big-endian support was abandoned by AMD/Linux. Maybe jsg@ > > knows. > > There are references to the previous generation (Northern Islands) > working on big-endian platforms. > > https://lists.freedesktop.org/archives/xorg-announce/2011-March/001628.html > "kms: evergreen/ni big endian accel support" > > Codenames are described in https://www.x.org/wiki/RadeonFeature/ > > https://lists.freedesktop.org/archives/amd-gfx/2018-June/023022.html > > "AFAIK all GPUs supported by amdgpu simply don't have these byte > swapping capabilities anymore" > > Use of RDNA cards (which have DCN display blocks) is also limited to a > small number of architectures as floating-point is used. Gated by > CONFIG_DRM_AMD_DC_DCN. > > The low end of radeon cards has also moved from PCIe 3.0 x8 electrical > on GCN parts to PCIe 4.0 x4 on RDNA2 parts. So a GCN part may even > be preferred on amd64 machines with PCIe <= 3.0.
It is worth noting that pre-GCN cards can not output at 4k resolutions. For example a Radeon HD 6450 which is CAICOS/Northern Islands based: DisplayPort 1.2 Max resolution: 2560x1600 HDMI 1.4a Max resolution: 1920x1200 Dual-link DVI Max resolution: 2560x1600 VGA Max resolution: 2048x1536 from http://web.archive.org/web/20180204040538/https://www.amd.com/en-us/products/graphics/desktop/6000/6450 A Radeon HD 7750 which is CAPE VERDE/Southern Islands based: DisplayPort 1.2 Maximum resolution: 4096x2160 @ 60 Hz HDMI Maximum resolution: 4096x2160 @ 30 Hz Dual-link DVI Maximum resolution: 2560x1600 VGA Maximum resolution: 2048x1536 from http://web.archive.org/web/20180202144726/http://www.amd.com/en-us/products/graphics/desktop/7000/7700 A Radeon RX 550 which is POLARIS12 based: DisplayPort: 5120×2880@60Hz HDMI: 4096×2160@60Hz DVI:2560x1600@60Hz from https://www.sapphiretech.com/en/consumer/pulse-rx-550-4g-g5#Specification
