storcli: howto crossflash Fujitsu PRAID400i to LSI3008 HBA?

Hello out there.

I have a bunch of Fujitsu PRAID400i Controller from some servers we switch to
FreeBSD driven systems and ZFS. I will not use RAID controllers with ZFS so I
tried to cross flash these controllers, but without any success. The DOS tools
I use produce on several mainboards a PAL error. The motherboard's UEFI I
uitilise doesn't provide a UEFI shell, so at that point it seems I'm stuck. I
found the FreeBSD port storcli, but the tool doesn't crossflash - or it doesn't
reveal its magic knobs to do so.

The sas3flash FreeBSD binary imag from Broadcom
https://www.broadcom.com/products/storage/host-bus-adapters/sas-9300-8i

doesn't recognize the test adapter (the adapters seem to have different stages
of firmware brandings, some from 2015 do have Avago, other, newer from 2019,
seem to be branded with Broadcom):

pciconf -lvbc

mrsas0@pci0:1:0:0:      class=0x010400 rev=0x02 hdr=0x00 vendor=0x1000
device=0x005f subvendor=0x1734 subdevice=0x1211
    vendor     = 'Broadcom / LSI'
    device     = 'MegaRAID SAS-3 3008 [Fury]'
    class      = mass storage
    subclass   = RAID
    bar   [10] = type I/O Port, range 32, base 0xe000, size 256, enabled
    bar   [14] = type Memory, range 64, base 0xfb300000, size 65536, enabled
    bar   [1c] = type Memory, range 64, base 0xfb200000, size 1048576, enabled
    cap 01[50] = powerspec 3  supports D0 D1 D2 D3  current D0
    cap 10[68] = PCI-Express 2 endpoint max data 256(4096) FLR NS
                 max read 512
                 link x4(x8) speed 8.0(8.0) ASPM disabled(L0s)
    cap 05[a8] = MSI supports 1 message, 64 bit, vector masks
    cap 11[c0] = MSI-X supports 97 messages, enabled
                 Table in map 0x14[0xe000], PBA in map 0x14[0xf000]
    ecap 0001[100] = AER 2 0 fatal 0 non-fatal 1 corrected
    ecap 0019[1e0] = PCIe Sec 1 lane errors 0
    ecap 0004[1c0] = Power Budgeting 1
    ecap 0016[190] = DPA 1
    ecap 000e[148] = ARI 1

The sas3flash utility reports:

# /tmp/Installer_P16_for_FreeBSD/sas3flash_freebsd_amd64_rel/sas3flash
Avago Technologies SAS3 Flash Utility
Version 17.00.00.00 (2018.04.02)
Copyright 2008-2018 Avago Technologies. All rights reserved.

        No Avago SAS adapters found! Limited Command Set Available!
        Finished Processing Commands Successfully.
        Exiting SAS3Flash.



Does anyone have had success on flashing this type of SAS controller from IR
firmware to IT firmware?

Thanks in advance,

oliver