Ok. So you recommend I stop "hacking" the CFI probing and instead write a custom flash map driver?
No. Never write new drivers when you can use existing ones :-)
Describe the flash memory as "mtd-ram" (instead of "cfi-flash") in the device tree and select the physmap driver in your kernel config.
Hi Wolfgang, I did as you recommended and replaced cfi-flash with mtd-ram in the device tree. I also defined CONFIG_MTD_PHYSMAP_OF, CONFIG_MTD_MTDRAM, CONFIG_MTDRAM_TOTAL_SIZE according to our specifications. The default erase-size was 128k, which is what we have too, so I didn't touch that. Now when I boot the kernel recognizes all the partitions I've defined in the dts. But, when mounting a jffs2-filesystem, it ends with a jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found...
Do you have any other tips?
When working with this, I realised that if I could get it to work we'd still might have a problem. You see, we need write access for one of the flashes when upgrading software. We can't treat this as a simple ROM. So do we need CFI working in order to set the device into write-mode, erase flash sectors, etc.? Or do mtd-ram handle flash write operations too?
In theory, I guess I could unmount the root fs, unload the mtd module, insert the cfi-flash module, mount the filesystem, then write, etc.. But isn't that harder than write a custom map driver?
Best regards, Frank