uname -a Linux alarmpi 3.18.7-3-ARCH #1 PREEMPT Fri Feb 13 06:28:50 MST 2015 armv61 GNU/Linux
pacman -Qs linux-raspberrypi local/linux-raspberrypi 3.18.7-3 The Linux Kernel and modules - Raspberry Pi local/linux-raspberrypi-headers 3.18.7-3 Header files and scripts for building modules for linux kernel - Raspberry Pi
Thank you. It's solved. I didn't know about it, because i followed guide on enabling spidev prepared for rapsbian. I didn't find anything for arch. Could you post link to some reliable resource i can use?