The only thing I see which differs from my setup is the kernel as I am using 6.4.
Let me say - older kernels like 5.10 and 5.15 is not likely to work well with your hardware.
I am going to suggest you install linux64 in your chroot (I noted you cannot even get into TTY)
Another option is to navigate - in chroot -
cd /var/cache/pacman/pkg
ls amd-ucode*
The current package is named amd-ucode-20230810.7be2766d-1-any.pkg.tar.xz
- Testing update 2023-08-09 - Comment 11
- Testing update 2023-08-09 - Comment 12
- Testing update 2023-08-09 - Comment 14
- Testing update 2023-08-09 - Comment 16
It may work or it may not - you can use pacman -U to install the previous amd-ucode from your cache - possibly (from memory - please check your listing for correct filename)
pacman -U amd-ucode-20230724.59fbffa9-1-any.pkg.tar.zst