diff options
| author | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2007-02-05 21:18:19 +0100 |
|---|---|---|
| committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2007-02-05 21:18:19 +0100 |
| commit | d54853ef8cb17296ac7bce9c77430fb7c80532d0 (patch) | |
| tree | 649e14d532e17231225a042a7c9a3d9207ad91ee /drivers/s390/s390mach.h | |
| parent | c1821c2e9711adc3cd298a16b7237c92a2cee78d (diff) | |
[S390] ETR support.
This patch adds support for clock synchronization to an external time
reference (ETR). The external time reference sends an oscillator
signal and a synchronization signal every 2^20 microseconds to keep
the TOD clocks of all connected servers in sync. For availability
two ETR units can be connected to a machine. If the clock deviates
for more than the sync-check tolerance all cpus get a machine check
that indicates that the clock is out of sync. For the lovely details
how to get the clock back in sync see the code below.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'drivers/s390/s390mach.h')
| -rw-r--r-- | drivers/s390/s390mach.h | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/s390/s390mach.h b/drivers/s390/s390mach.h index 7abb42a09ae..d3ca4281a49 100644 --- a/drivers/s390/s390mach.h +++ b/drivers/s390/s390mach.h @@ -102,4 +102,7 @@ static inline int stcrw(struct crw *pcrw ) return ccode; } +#define ED_ETR_SYNC 12 /* External damage ETR sync check */ +#define ED_ETR_SWITCH 13 /* External damage ETR switch to local */ + #endif /* __s390mach */ |