loading drm crashes system

Hello:
	On a system now running:

14.0-CURRENT FreeBSD 14.0-CURRENT #0 main-d6327ae8c1: Sun Jan 24
14:16:54 EST 2021 amd64

	(src+ports updated at midnight US EST)
	with PORTS_MODULES="drm-current-kmod gpu-firmware-kmod", starting
the system _without_ loading drm results in a usable system.
	Loading drm - whether via kldlist in rc.conf or by kldload at the
console immediately after start-up - instantly crashes the system; the
screen goes blank and the lights on the monitor report no signal
from the system.
	There is nothing in dmesg.boot.
	In messages I find (75 lines follow):

Jan 24 17:35:22 jerusalem kernel: [drm:drm_core_init] Initialized
Jan 24 17:35:22 jerusalem kernel: [drm] radeon kernel modesetting enabled.
Jan 24 17:35:22 jerusalem kernel: drmn0: <drmn> on vgapci0
Jan 24 17:35:22 jerusalem kernel: vgapci0: child drmn0 requested pci_enable_io
Jan 24 17:35:22 jerusalem kernel: [drm:drm_minor_register] 
Jan 24 17:35:22 jerusalem kernel: [drm:drm_minor_register] new minor registered 128
Jan 24 17:35:22 jerusalem kernel: [drm:drm_minor_register] 
Jan 24 17:35:22 jerusalem kernel: [drm:drm_minor_register] new minor registered 0
Jan 24 17:35:22 jerusalem kernel: [drm] initializing kernel modesetting (RS780 0x1002:0x9614 0x1849:0x9614 0x00).
Jan 24 17:35:22 jerusalem kernel: [drm:radeon_get_bios] ATOMBIOS detected
Jan 24 17:35:22 jerusalem kernel: [drm ERROR :radeon_atombios_init] Unable to find PCI I/O BAR; using MMIO for ATOM IIO
Jan 24 17:35:22 jerusalem kernel: [drm:atom_allocate_fb_scratch] atom firmware requested 17ffb000 20kb
Jan 24 17:35:22 jerusalem kernel: drmn0: VRAM: 384M 0x00000000C0000000 - 0x00000000D7FFFFFF (384M used)
Jan 24 17:35:22 jerusalem kernel: drmn0: GTT: 512M 0x00000000A0000000 - 0x00000000BFFFFFFF
Jan 24 17:35:22 jerusalem kernel: [drm] Detected VRAM RAM=384M, BAR=256M
Jan 24 17:35:22 jerusalem kernel: [drm] RAM width 32bits DDR
Jan 24 17:35:22 jerusalem kernel: [drm] radeon: 384M of VRAM memory ready
Jan 24 17:35:22 jerusalem kernel: [drm] radeon: 512M of GTT memory ready.
Jan 24 17:35:22 jerusalem kernel: [drm:r600_init_microcode] 
Jan 24 17:35:22 jerusalem kernel: [drm] Loading RS780 Microcode
Jan 24 17:35:23 jerusalem kernel: drmn0: fail (0) to get firmware image with name: radeon/RS780_pfp.bin
Jan 24 17:35:23 jerusalem kernel: drmn0: successfully loaded firmware image with mapped name: radeon_RS780_pfp_bin
Jan 24 17:35:23 jerusalem kernel: drmn0: fail (0) to get firmware image with name: radeon/RS780_me.bin
Jan 24 17:35:23 jerusalem kernel: drmn0: successfully loaded firmware image with mapped name: radeon_RS780_me_bin
Jan 24 17:35:24 jerusalem kernel: drmn0: fail (0) to get firmware image with name: radeon/R600_rlc.bin
Jan 24 17:35:24 jerusalem kernel: drmn0: successfully loaded firmware image with mapped name: radeon_R600_rlc_bin
Jan 24 17:35:24 jerusalem kernel: [drm:radeon_pm_print_states] 3 Power State(s)
Jan 24 17:35:24 jerusalem kernel: [drm:radeon_pm_print_states] State 0: 
Jan 24 17:35:24 jerusalem kernel: [drm:radeon_pm_print_states] 	Default[drm:radeon_pm_print_states] 	1 Clock Mode(s)
Jan 24 17:35:24 jerusalem kernel: [drm:radeon_pm_print_states] 		0 e: 800000
Jan 24 17:35:24 jerusalem kernel: [drm:radeon_pm_print_states] State 1: Performance
Jan 24 17:35:24 jerusalem kernel: [drm:radeon_pm_print_states] 	1 Clock Mode(s)
Jan 24 17:35:24 jerusalem kernel: [drm:radeon_pm_print_states] 		0 e: 500000
Jan 24 17:35:24 jerusalem kernel: [drm:radeon_pm_print_states] State 2: 
Jan 24 17:35:24 jerusalem kernel: [drm:radeon_pm_print_states] 	1 Clock Mode(s)
Jan 24 17:35:24 jerusalem kernel: [drm:radeon_pm_print_states] 		0 e: 500000
Jan 24 17:35:24 jerusalem kernel: [drm] radeon: power management initialized
Jan 24 17:35:24 jerusalem kernel: drmn0: fail (0) to get firmware image with name: radeon/RS780_uvd.bin
Jan 24 17:35:24 jerusalem kernel: drmn0: successfully loaded firmware image with mapped name: radeon_RS780_uvd_bin
Jan 24 17:35:24 jerusalem kernel: [drm] GART: num cpu pages 131072, num gpu pages 131072
Jan 24 17:35:34 jerusalem kernel: [drm] PCIE GART of 512M enabled (table at 0x00000000C0146000).
Jan 24 17:35:34 jerusalem kernel: drmn0: WB enabled
Jan 24 17:35:34 jerusalem kernel: drmn0: fence driver on ring 0 use gpu addr 0x00000000a0000c00 and cpu addr 0x0xfffff801cb29cc00
Jan 24 17:35:34 jerusalem kernel: drmn0: fence driver on ring 5 use gpu addr 0x00000000c0056038 and cpu addr 0x0xfffff800d0056038
Jan 24 17:35:34 jerusalem kernel: [drm] Supports vblank timestamp caching Rev 2 (21.10.2013).
Jan 24 17:35:34 jerusalem kernel: [drm] Driver supports precise vblank timestamp query.
Jan 24 17:35:34 jerusalem kernel: drmn0: radeon: MSI limited to 32-bit
Jan 24 17:35:34 jerusalem kernel: [drm:drm_irq_install] irq=18
Jan 24 17:35:34 jerusalem kernel: [drm] radeon: irq initialized.
Jan 24 17:35:34 jerusalem kernel: [drm:r600_irq_process] r600_irq_process start: rptr 0, wptr 32
Jan 24 17:35:34 jerusalem kernel: [drm:r600_irq_process] IH: D1 flip
Jan 24 17:35:34 jerusalem kernel: [drm:r600_irq_process] IH: D2 flip
Jan 24 17:35:34 jerusalem kernel: [drm] ring test on 0 succeeded in 1 usecs
Jan 24 17:35:34 jerusalem kernel: [drm ERROR :uvd_v1_0_start] UVD not responding, trying to reset the VCPU!!!
Jan 24 17:35:35 jerusalem kernel: [drm ERROR :uvd_v1_0_start] UVD not responding, giving up!!!
Jan 24 17:35:35 jerusalem kernel: drmn0: failed initializing UVD (-1).
Jan 24 17:35:35 jerusalem kernel: [drm:r600_irq_set] r600_irq_set: sw int
Jan 24 17:35:35 jerusalem kernel: [drm] ib test on ring 0 succeeded in 0 usecs
Jan 24 17:35:35 jerusalem kernel: [drm:radeon_atombios_get_tv_info] Unknown TV standard; defaulting to NTSC
Jan 24 17:35:35 jerusalem kernel: [drm] Connector VGA-1: get mode from tunables:
Jan 24 17:35:35 jerusalem kernel: [drm]   - kern.vt.fb.modes.VGA-1
Jan 24 17:35:35 jerusalem kernel: [drm]   - kern.vt.fb.default_mode
Jan 24 17:35:35 jerusalem kernel: [drm:drm_connector_get_cmdline_mode] cmdline mode for connector VGA-1  800x600_at_60Hz
Jan 24 17:35:35 jerusalem kernel: [drm:drm_sysfs_connector_add] adding "VGA-1" to sysfs
Jan 24 17:35:35 jerusalem kernel: [drm:drm_sysfs_hotplug_event] generating hotplug event
Jan 24 17:35:35 jerusalem kernel: [drm] Connector DVI-D-1: get mode from tunables:
Jan 24 17:35:35 jerusalem kernel: [drm]   - kern.vt.fb.modes.DVI-D-1
Jan 24 17:35:35 jerusalem kernel: [drm]   - kern.vt.fb.default_mode
Jan 24 17:35:35 jerusalem kernel: [drm:drm_connector_get_cmdline_mode] cmdline mode for connector DVI-D-1  800x600_at_60Hz
Jan 24 17:35:35 jerusalem kernel: [drm:drm_sysfs_connector_add] adding "DVI-D-1" to sysfs
Jan 24 17:35:35 jerusalem kernel: [drm:drm_sysfs_hotplug_event] generating hotplug event
Jan 24 17:35:35 jerusalem kernel: [drm] Radeon Display Connectors
Jan 24 17:35:35 jerusalem kernel: [drm] Connector 0:
Jan 24 17:35:35 jerusalem kernel: [drm]   VGA-1
Jan 24 17:35:35 jerusalem kernel: [drm]   DDC: 0x7e40 0x7e40 0x7e44 0x7e44 0x7e48 0x7e48 0x7e4c 0x7e4c
Jan 24 17:35:35 jerusalem kernel: [drm]   Encoders:
Jan 24 17:35:35 jerusalem kernel: [drm]     CRT1: INTERNAL_KLDSCP_DAC1
Jan 24 17:35:35 jerusalem kernel: [drm] Connector 1:
Jan 24 17:35:35 jerusalem kernel: [drm]   DVI-D-1
Jan 24 17:35:35 jerusalem kernel: [drm]   HPD3
Jan 24 17:35:35 jerusalem kernel: [drm]   DDC: 0x7e50 0x7e50 0x7e54 0x7e54 0x7e58 0x7e58 0x7e5c 0x7e5c
Jan 24 17:35:35 jerusalem kernel: [drm]   Encoders:
Jan 24 17:35:35 jerusalem kernel: [drm]     DFP3: INTERNAL_KLDSCP_LVTMA
Jan 24 17:35:35 jerusalem kernel: [drm:r600_irq_set] r600_irq_set: hpd 3
Jan 24 17:35:35 jerusalem kernel: [drm:radeon_atom_encoder_dpms] encoder dpms 21 to mode 3, devices 00000001, active_devices 00000000
Jan 24 17:35:35 jerusalem kernel: [drm:radeon_atom_encoder_dpms] encoder dpms 31 to mode 3, devices 00000200, active_devices 00000000
Jan 24 17:35:35 jerusalem kernel: [drm:drm_crtc_vblank_off] crtc 0, vblank enabled 0, inmodeset 0
Jan 24 17:35:35 jerusalem kernel: [drm:drm_crtc_vblank_off] crtc 1, vblank enabled 0, inmodeset 0
Jan 24 17:35:35 jerusalem kernel: [drm:drm_client_modeset_probe] 
Jan 24 17:35:35 jerusalem kernel: [drm:drm_mode_object_get] OBJ ID: 46 (2)
Jan 24 17:35:35 jerusalem kernel: [drm:drm_mode_object_get] OBJ ID: 48 (2)
Jan 24 17:35:35 jerusalem kernel: [drm:drm_helper_probe_single_connector_modes] [CONNECTOR:46:VGA-1]
Jan 24 17:35:35 jerusalem kernel: [drm] Cannot find any crtc or sizes
Jan 24 17:35:35 jerusalem kernel: [drm] Initialized radeon 2.50.0 20080528 for drmn0 on minor 0
Jan 24 17:35:36 jerusalem kernel: [drm] Cannot find any crtc or sizes

	[insert image of open jaw and glassy-eyed stare]
	The GPU is a Radeon HD 3300, and at one point this used to work.
	Help, please?


			Respectfully,


				Robert Huff