Then I try faster card. zImages boot fine from it, but fast cfcard is not visible from linux after boot.
With xeno advice I made some test and found this:
card X: new one (originally formated ext2/32G , later ext2/4G, FAT16/4G, FAT16/256M)
SanDisk Extreme, 32GB, up to 120MB/s read speed; up to 85MB/s write speed, VPG-20, UDMA 7 ( specs from SanDisk site)
card Y: old one (formatted ext2/4G)
SanDisk Ultra, 4GB, up to 25MB/s read; write speed lower, Compatible with CompactFlash supporting host devices ( specs from SanDisk site)
- card X can be used for zImages, card Y not (I/O errors)
- card Y is visible from all booted systems ( Debian8 or Fienix ) with all tested kernels
- card X is visible only in systems booted with kernels 4.2, 4.4, 4.5, 4.7, 4.9.0-alpha1
and not visible with kernels 4.9.85, 4.14, 4.19, 4.20, 5.0, 5.1, 5.1-rc5
then I compared dmesg from 4.9.0-alpha1 and 4.9.85. The most suspicious I found this:
kernel 4.9.0-alpha1: card X recognized like pata_of_platform
Code: Select all
pata_of_platform f0000000.cf: pio-mode unspecified, assuming PIO0
Code: Select all
scsi 6:0:0:0: Direct-Access ATA SDCFXS-032G 6.01 PQ: 0 ANSI: 5
sd 6:0:0:0: [sdd] 62537328 512-byte logical blocks: (32.0 GB/29.8 GiB)
Code: Select all
electra-cf f0000000.cf: at mem 0xf0000000 io 0xf1000000 irq 17
Also I don't know, on what depend selection pata_of_platform vs. electra-cf - speed, size, UDMA capability?
Now I will test which exact kernel version 4.9.x is first with this issue, and also check what type (pata_of_platform vs. electra-cf) is old card Y on new kernel.