Comment 104 for bug 1874194

Same issue on my Dell 5520

When I REBOOT and the HDMI 2nd monitor is connected, splash screen freezes.

_________
Specs:
Xubuntu 20.04

uname -r
5.8.0-59-generic

lspci -vvv
Graphics:
0000:00:02.0 VGA compatible controller: Intel Corporation Device 9a49 (rev 01) (prog-if 00 [VGA controller])
 Subsystem: Dell Device 0a21
 Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+
 Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
 Latency: 0
 Interrupt: pin A routed to IRQ 169
 Region 0: Memory at 6054000000 (64-bit, non-prefetchable) [size=16M]
 Region 2: Memory at 4000000000 (64-bit, prefetchable) [size=256M]
 Region 4: I/O ports at 3000 [size=64]
 Expansion ROM at 000c0000 [virtual] [disabled] [size=128K]
 Capabilities: <access denied>
 Kernel driver in use: i915
 Kernel modules: i915

dmesg --level=err,warn
[ 1.039745] Missing case (clock == 539440)
[ 1.039795] WARNING: CPU: 3 PID: 193 at drivers/gpu/drm/i915/display/intel_dpll_mgr.c:2967 icl_calc_dpll_state.isra.0+0x21d/0x280 [i915]

[ 1.039828] RIP: 0010:icl_calc_dpll_state.isra.0+0x21d/0x280 [i915]
[ 1.039829] Code: 4c 63 c2 39 cf 74 55 48 83 c2 01 48 83 fa 08 75 e5 48 63 d7 48 c7 c6 ee b5 7f c0 48 c7 c7 e3 b4 7f c0 88 45 bf e8 ab 32 5e c8 <0f> 0b 0f b6 45 bf e9 ea fe ff ff 31 d2 be 54 00 60 00 e9 9b fe ff
[ 1.039830] RSP: 0018:ffffb460805eb6c8 EFLAGS: 00010282
[ 1.039830] RAX: 0000000000000000 RBX: ffffa00c5795a490 RCX: 00000000000003bb
[ 1.039831] RDX: 0000000000000001 RSI: 0000000000000086 RDI: 0000000000000247
[ 1.039831] RBP: ffffb460805eb710 R08: 00000000000003bb R09: 0000000000000004
[ 1.039831] R10: 0000000000000000 R11: 0000000000000001 R12: ffffa00c5795a000
[ 1.039832] R13: ffffa00c58820000 R14: ffffa00c68dea800 R15: ffffa00c5795c000
[ 1.039832] FS: 00007f60162cc880(0000) GS:ffffa00c6f6c0000(0000) knlGS:0000000000000000
[ 1.039833] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1.039833] CR2: 00007fff1750bec0 CR3: 000000085902a002 CR4: 0000000000760ee0
[ 1.039833] PKRU: 55555554
[ 1.039834] Call Trace:
[ 1.039857] icl_get_dplls+0x34b/0x840 [i915]
[ 1.039870] ? drm_mode_object_get+0x2a/0x60 [drm]
[ 1.039877] ? drm_connector_list_iter_next+0x8e/0xb0 [drm]
[ 1.039898] intel_reserve_shared_dplls+0x24/0x60 [i915]
[ 1.039920] hsw_crtc_compute_clock+0x5a/0x90 [i915]
[ 1.039941] intel_atomic_check_crtcs+0x3ba/0x620 [i915]
[ 1.039961] ? icl_put_dplls+0x6c/0xb0 [i915]
[ 1.039980] intel_atomic_check+0xa22/0xb60 [i915]
[ 1.039982] ? __kmalloc_track_caller+0x271/0x280
[ 1.040004] ? intel_crtc_duplicate_state+0x27/0xb0 [i915]
[ 1.040011] drm_atomic_check_only+0x2c7/0x450 [drm]
[ 1.040017] drm_atomic_commit+0x18/0x50 [drm]
[ 1.040037] intel_modeset_init+0x456/0xae0 [i915]
[ 1.040055] i915_driver_probe+0x275/0x500 [i915]
[ 1.040058] ? _cond_resched+0x19/0x30
[ 1.040059] ? mutex_lock+0x13/0x40
[ 1.040077] i915_pci_probe+0x5a/0x140 [i915]
[ 1.040080] local_pci_probe+0x48/0x80
[ 1.040081] pci_device_probe+0x10f/0x1b0
[ 1.040083] really_probe+0x159/0x3d0
[ 1.040084] driver_probe_device+0xe9/0x160
[ 1.040085] device_driver_attach+0x5d/0x70
[ 1.040086] __driver_attach+0x8f/0x150
[ 1.040087] ? device_driver_attach+0x70/0x70
[ 1.040087] bus_for_each_dev+0x7e/0xc0
[ 1.040088] driver_attach+0x1e/0x20
[ 1.040089] bus_add_driver+0x152/0x1f0
[ 1.040089] driver_register+0x74/0xd0
[ 1.040090] __pci_register_driver+0x54/0x60
[ 1.040109] i915_init+0x61/0x75 [i915]
[ 1.040110] ? 0xffffffffc0890000
[ 1.040112] do_one_initcall+0x4a/0x200
[ 1.040113] ? vfree+0x2c/0x40
[ 1.040114] ? _cond_resched+0x19/0x30
[ 1.040115] ? kmem_cache_alloc_trace+0x1b0/0x240
[ 1.040116] do_init_module+0x62/0x250
[ 1.040117] load_module+0x1185/0x1390
[ 1.040119] ? ima_post_read_file+0x108/0x120
[ 1.040120] __do_sys_finit_module+0xc9/0x130
[ 1.040121] ? __do_sys_finit_module+0xc9/0x130
[ 1.040122] __x64_sys_finit_module+0x1a/0x20
[ 1.040123] do_syscall_64+0x49/0xc0
[ 1.040124] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[ 1.040124] RIP: 0033:0x7f601684e89d