Pi4 not booting with a Pi3 (Sarpi) card. Any hint ?

Hello everyone,
I've just got a Pi4 ( model B ) 4G to replace my loved Pi3.
I would like to transfer directly the sd-card from Pi3 to Pi4 so I don't have to rebuild everything.

I have then put the new SD card in the usb adapter, created 3 partitions ( vfat, swap, and ext4 )
On the vfat I've copied config.txt,cmdline.txt, kernel.img and System.map from my Pi3 and all other files and overlays from the newly arrived Pi4 sd card, and cpio'ed all other files on the ext4.

It almost works, but it stops just after
Code:[ ] bcm2835-power bcm2835-power; Broadcom BCM2835 power domains driver
[ ] mnc-bcm2835 fe300000.mmenr: mmcdebug:0 mmc_debug2:0
[ ] mmc-bcm2835 1e300000.mmcnr: mmc-bcm2835: Unable to initialise DMA channel. Falling back to PIO
[ ] of_jcfs_init
[ ] of_cfs_init: OK
[ ] Waiting for root device /dev/mmcblk0p3
[ ] mmc1: queuing unknown CIS tuple 0x80 (3 bytes)
[ ] mmc1: queuing unknown CIS tuple 0x80 (3 bytes)
[ ] mmc1: queuing unknown CIS tuple 0x80 (3 bytes)
[ ] mmc1: queuing unknown CIS tuple 0x80 (3 bytes)
[ ] random: fast init done
[ ] mmc1: new high speed SDIO card at address 0001After this last message it hangs there without any other message and also after waiting quite a lot f time it don't goes on.

Any hint on what to check ?

Thanks in advance

Pigi