HelenOS sources

icp_irqc_mask     171 kernel/arch/arm32/src/mach/integratorcp/integratorcp.c 	icp_irqc_mask(ICP_TIMER_IRQ);
icp_irqc_mask     331 kernel/arch/arm32/src/mach/integratorcp/integratorcp.c 			icp_irqc_mask(ICP_KBD_IRQ);
HelenOS homepage, sources at GitHub