could you dmesg |grep -ie pvr_k -ie rgx -ie drm ?
mine looks like this:
$ uname -a
Linux VF2-A 5.15.2-cwt-3.0.4-2 #1 SMP PREEMPT Wed Jun 14 01:20:40 +07 2023 riscv64 GNU/Linux
$ dmesg |grep -ie pvr_k -ie rgx -ie drm
[ 0.646801] PVR_K: 1: Read BVNC 36.50.54.182 from HW device registers
[ 0.646874] PVR_K: 1: RGX Device registered BVNC 36.50.54.182 with 1 core in the system
[ 0.792378] PVR_K: 1: RGX Firmware image 'rgx.fw.36.50.54.182' loaded
[ 0.796462] PVR_K: 1: Shader binary image 'rgx.sh.36.50.54.182' loaded
[ 0.798833] [drm] Initialized pvr 1.17.6210866 20170530 for 18000000.gpu on minor 0
[ 2.782652] innohdmi-starfive 29590000.hdmi: [drm:inno_hdmi_i2c_adapter] registered Inno HDMI I2C bus driver success
[ 2.783884] [drm] Initialized starfive 1.0.0 20191101 for soc:display-subsystem on minor 1
[ 3.284002] starfive soc:display-subsystem: [drm] Cannot find any crtc or sizes
[ 3.784230] starfive soc:display-subsystem: [drm] Cannot find any crtc or sizes
[ 4.284388] starfive soc:display-subsystem: [drm] Cannot find any crtc or sizes
[ 9.419763] systemd[1]: Starting Load Kernel Module drm...
[ 9.586787] systemd[1]: modprobe@drm.service: Deactivated successfully.
[ 9.587524] systemd[1]: Finished Load Kernel Module drm.
[ 39.085943] starfive soc:display-subsystem: [drm] fb0: starfive frame buffer device