I think I did it, I mentioned it in my first post. I followed this tuto.
Now I've made a big mistake. I went apocalyptic and wiped out my NAND and my NOR with:
erase mtd0 // NAND, kernel
erase mtd1 // NAND, filesystem
erase mtd2 // NAND, reserved-kernel ? what is it ?
erase mtd3 // NAND, reserved-filesystem ? what is it ?
erase mtd4 // NAND, config ? what is it ?
erase mtd5 // NAND, nand-filesystem ? what is it ?
erase mtd6 // NOR, urlader: bootloader
erase mtd7 // NOR, tffs ? what is it ?
erase mtd8 // NOR, tffs ? what is it ?
I know I know, BIG MISTAKE. Which means no more EVA bootloader, no more serial access, and no more ftp flashing as usual.
Hopefully I've made a backup of every mtdx.
So I was going to try to "JTAG" my fritzbox. But I think I don't need to.
Correct me guys if I'm wrong, but I only need to flash the NOR (mine is MX25L2006E) which contains the bootloader. And once I got the bootloader back, I should be able to flash the NAND via ftp.
In order to flash the NOR, I've already got my backup, the flashrom utility, a CH341A programmer and a SOIC8 Clip, that I previously used to flash some ThinkPad X230 BIOS.
I'm about to proceed. Any advice is welcome. 