1 /* 2 * same structure to x86's 3 * Hopefully asm-x86/pvclock-abi.h would be moved to somewhere more generic. 4 * For now, define same duplicated definitions. 5 */ 6 7 #ifndef _ASM_IA64__PVCLOCK_ABI_H 8 #define _ASM_IA64__PVCLOCK_ABI_H 9 #ifndef __ASSEMBLY__ 10 11 /* 12 * These structs MUST NOT be changed. 13 * They are the ABI between hypervisor and guest OS. 14 * Both Xen and KVM are using this. 15 * 16 * pvclock_vcpu_time_info holds the system time and the tsc timestamp 17 * of the last update. So the guest can use the tsc delta to get a 18 * more precise system time. There is one per virtual cpu. 19 * 20 * pvclock_wall_clock references the point in time when the system 21 * time was zero (usually boot time), thus the guest calculates the 22 * current wall clock by adding the system time. 23 * 24 * Protocol for the "version" fields is: hypervisor raises it (making 25 * it uneven) before it starts updating the fields and raises it again 26 * (making it even) when it is done. Thus the guest can make sure the 27 * time values it got are consistent by checking the version before 28 * and after reading them. 29 */ 30 31 struct pvclock_vcpu_time_info { 32 u32 version; 33 u32 pad0; 34 u64 tsc_timestamp; 35 u64 system_time; 36 u32 tsc_to_system_mul; 37 s8 tsc_shift; 38 u8 pad[3]; 39 } __attribute__((__packed__)); /* 32 bytes */ 40 41 struct pvclock_wall_clock { 42 u32 version; 43 u32 sec; 44 u32 nsec; 45 } __attribute__((__packed__)); 46 47 #endif /* __ASSEMBLY__ */ 48 #endif /* _ASM_IA64__PVCLOCK_ABI_H */ 49