I droped GPE0_EN initialization from coreboot and now it works. I think OS gets GPE0_EN information from _PRW objects in ACPI tables. So... Is there any reason to setup GPE0_EN register in coreboot?
Little addition to my last message: Not even drop GPE0_EN initialization from coreboot, but add GPE0_EN reset to 0x00000000. Cause coreboot gets it initializated from OS. Should it be done this way, or it is terrible hack?