| Isaku Yamahata | 25c7bfa | 2008-10-17 11:17:50 +0900 | [diff] [blame] | 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 */ |