Here is an amdgpu-firmware update for after unlock.
The linux 4.19 based drm in -current should be fine with this.
Index: Makefile
===================================================================
RCS file: /cvs/ports/sysutils/firmware/amdgpu/Makefile,v
retrieving revision 1.2
diff -u -p -r1.2 Makefile
--- Makefile 3 Jul 2019 05:25:29 -0000 1.2
+++ Makefile 29 Apr 2020 02:51:34 -0000
@@ -1,7 +1,7 @@
# $OpenBSD: Makefile,v 1.2 2019/07/03 05:25:29 jsg Exp $
FW_DRIVER= amdgpu
-FW_VER= 20190312
+FW_VER= 20200421
DISTNAME= linux-firmware-${FW_VER}
EXTRACT_SUFX= .tar.xz
Index: distinfo
===================================================================
RCS file: /cvs/ports/sysutils/firmware/amdgpu/distinfo,v
retrieving revision 1.2
diff -u -p -r1.2 distinfo
--- distinfo 3 Jul 2019 05:25:29 -0000 1.2
+++ distinfo 29 Apr 2020 02:52:01 -0000
@@ -1,2 +1,2 @@
-SHA256 (firmware/linux-firmware-20190312.tar.xz) =
7R5dYEUBX1QO+JZ4IqhSR3ScaGbQdHmhczHcf1gVIyE=
-SIZE (firmware/linux-firmware-20190312.tar.xz) = 78781204
+SHA256 (firmware/linux-firmware-20200421.tar.xz) =
bdfLol1pTAMfZVKbkCfMj6r/rd+ucKTjtYwuSgrzv6g=
+SIZE (firmware/linux-firmware-20200421.tar.xz) = 98988760
Index: pkg/PLIST
===================================================================
RCS file: /cvs/ports/sysutils/firmware/amdgpu/pkg/PLIST,v
retrieving revision 1.2
diff -u -p -r1.2 PLIST
--- pkg/PLIST 3 Jul 2019 05:25:29 -0000 1.2
+++ pkg/PLIST 29 Apr 2020 02:53:43 -0000
@@ -83,6 +83,39 @@ firmware/amdgpu/mullins_sdma.bin
firmware/amdgpu/mullins_sdma1.bin
firmware/amdgpu/mullins_uvd.bin
firmware/amdgpu/mullins_vce.bin
+firmware/amdgpu/navi10_asd.bin
+firmware/amdgpu/navi10_ce.bin
+firmware/amdgpu/navi10_gpu_info.bin
+firmware/amdgpu/navi10_me.bin
+firmware/amdgpu/navi10_mec.bin
+firmware/amdgpu/navi10_mec2.bin
+firmware/amdgpu/navi10_pfp.bin
+firmware/amdgpu/navi10_rlc.bin
+firmware/amdgpu/navi10_sdma.bin
+firmware/amdgpu/navi10_sdma1.bin
+firmware/amdgpu/navi10_smc.bin
+firmware/amdgpu/navi10_sos.bin
+firmware/amdgpu/navi10_ta.bin
+firmware/amdgpu/navi10_vcn.bin
+firmware/amdgpu/navi14_asd.bin
+firmware/amdgpu/navi14_ce.bin
+firmware/amdgpu/navi14_ce_wks.bin
+firmware/amdgpu/navi14_gpu_info.bin
+firmware/amdgpu/navi14_me.bin
+firmware/amdgpu/navi14_me_wks.bin
+firmware/amdgpu/navi14_mec.bin
+firmware/amdgpu/navi14_mec2.bin
+firmware/amdgpu/navi14_mec2_wks.bin
+firmware/amdgpu/navi14_mec_wks.bin
+firmware/amdgpu/navi14_pfp.bin
+firmware/amdgpu/navi14_pfp_wks.bin
+firmware/amdgpu/navi14_rlc.bin
+firmware/amdgpu/navi14_sdma.bin
+firmware/amdgpu/navi14_sdma1.bin
+firmware/amdgpu/navi14_smc.bin
+firmware/amdgpu/navi14_sos.bin
+firmware/amdgpu/navi14_ta.bin
+firmware/amdgpu/navi14_vcn.bin
firmware/amdgpu/oland_ce.bin
firmware/amdgpu/oland_k_smc.bin
firmware/amdgpu/oland_mc.bin
@@ -100,6 +133,7 @@ firmware/amdgpu/picasso_pfp.bin
firmware/amdgpu/picasso_rlc.bin
firmware/amdgpu/picasso_rlc_am4.bin
firmware/amdgpu/picasso_sdma.bin
+firmware/amdgpu/picasso_ta.bin
firmware/amdgpu/picasso_vcn.bin
firmware/amdgpu/pitcairn_ce.bin
firmware/amdgpu/pitcairn_k_smc.bin
@@ -178,18 +212,32 @@ firmware/amdgpu/raven2_mec2.bin
firmware/amdgpu/raven2_pfp.bin
firmware/amdgpu/raven2_rlc.bin
firmware/amdgpu/raven2_sdma.bin
+firmware/amdgpu/raven2_ta.bin
firmware/amdgpu/raven2_vcn.bin
firmware/amdgpu/raven_asd.bin
firmware/amdgpu/raven_ce.bin
firmware/amdgpu/raven_dmcu.bin
firmware/amdgpu/raven_gpu_info.bin
+firmware/amdgpu/raven_kicker_rlc.bin
firmware/amdgpu/raven_me.bin
firmware/amdgpu/raven_mec.bin
firmware/amdgpu/raven_mec2.bin
firmware/amdgpu/raven_pfp.bin
firmware/amdgpu/raven_rlc.bin
firmware/amdgpu/raven_sdma.bin
+firmware/amdgpu/raven_ta.bin
firmware/amdgpu/raven_vcn.bin
+firmware/amdgpu/renoir_asd.bin
+firmware/amdgpu/renoir_ce.bin
+firmware/amdgpu/renoir_dmcub.bin
+firmware/amdgpu/renoir_gpu_info.bin
+firmware/amdgpu/renoir_me.bin
+firmware/amdgpu/renoir_mec.bin
+firmware/amdgpu/renoir_mec2.bin
+firmware/amdgpu/renoir_pfp.bin
+firmware/amdgpu/renoir_rlc.bin
+firmware/amdgpu/renoir_sdma.bin
+firmware/amdgpu/renoir_vcn.bin
firmware/amdgpu/si58_mc.bin
firmware/amdgpu/stoney_ce.bin
firmware/amdgpu/stoney_me.bin