I am fully recompiled all Omega firmware, now my kernel have all spi drivers:

root@Omega-3079:/# lsmod | grep spi regmap_spi 1274 0 spi_bitbang 2661 1 spi_gpio spi_gpio 5424 0 spidev 6336 0

I also successfully compiled driver spi-gpio-driver-master using some additional required files from firmware sources. For example, onion-debug.h was found in i2c-exp-driver, etc.
After spi-gpio-driver-master compile I have spi-tool utility, libonionspi.so and python onionSpi.so module.

But I don't see soft-spi device in /dev:

root@Omega-3079:~# ls -l /dev/spi* crw------- 1 root root 153, 0 Dec 6 16:29 /dev/spidev0.1

/dev/spidev0.1 -- hardware SPI, used python3-spidev driver.
But spi-tool utility, libonionspi.so and python onionSpi.so used /dev/spidev%d.%d device too.

As I think spi_gpio driver should create some other device in /dev. May be I should run some "activate procedure" for spi_gpio kernel driver?
Or https://github.com/OnionIoT/spi-gpio-driver too old and it cannot work with some latest Omega's Linux kernels?

dmesg outputs only hardware /dev/spidev0.1:

root@Omega-3079:/# dmesg | grep spi [ 0.371163] spi-mt7621 10000b00.spi: sys_freq: 193333333 [ 0.382341] m25p80 spi0.0: mx25l25635e (32768 Kbytes) [ 0.387589] 5 fixed-partitions partitions found on MTD device spi0.0 [ 0.394049] Creating 5 MTD partitions on "spi0.0": root@Omega-3079:/#

any other spi device does not create.