HelenOS sources

VPN_SHIFT          54 kernel/arch/mips32/src/mm/tlb.c #define ADDR2HI_VPN(a)   ((a) >> VPN_SHIFT)
VPN_SHIFT          57 kernel/arch/mips32/src/mm/tlb.c #define HI_VPN2ADDR(vpn)    ((vpn) << VPN_SHIFT)
HelenOS homepage, sources at GitHub