There is a number of proprietary modules required for the hardware operation:
227128 1 aug 2008 miniuhci.ko 167551 1 aug 2008 padre_des.ko 599901 1 aug 2008 padre_gmac.ko 217699 1 aug 2008 padre_i2c_hwmon.ko 288547 1 aug 2008 padre_i2c.ko 211536 1 aug 2008 padre_i2c_rtc.ko 692820 1 aug 2008 padre_io.ko 212576 1 aug 2008 padre_lcd.ko 135906 1 aug 2008 padre_nand_flash.ko 133329 1 aug 2008 padre_nor_flash.ko 227896 1 aug 2008 padre_p0_led_button.ko 239071 1 aug 2008 padre_wb83782d.ko
These are all found in the encrypted initrd, outside of the harddrive based root filesystem. Source of these modules is not provided by Netgear, even if some seem to be heavily based on other existing modules. The 4.1.4 GPL source release do contain precompiled modules.
miniuhci purpose is isn't fully known, but it seems to be primitive USB UHCI driver.
padre_des is the driver for the hardware encryption unit.
padre_gmac is the gigabit ethernet driver.
padre_i2c* provides access to the I2C bus, where the RTC and some hardware monitors is located.
padre_i2c_rtc.ko provides access to the RTC chip over I2C. Based on the normal RTC driver by Paul Gortmaker but no source is provided.
padre_io is the main I/O driver, SATA, RAID, and also seems to contain the firmware for the "Data junktion" CPU core.
padre_lcd is the lcd driver for NV+ units?
padre_nor_flash maps the NOR flash used in old units.
padre_nand_flash maps the NAND flash used in Duo / NV+ units.
padre_p0_led_button leds & buttons on Duo / NV+ units?
padre_wb83782d provides access to a Winbond 83782D hardware monitor