s390/time: STP sync clock correction
The sync clock operation of the channel subsystem call for STP delivers
the TOD clock difference as a result. Use this TOD clock difference
instead of the difference between the TOD timestamps before and after
the sync clock operation.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/drivers/s390/cio/chsc.c b/drivers/s390/cio/chsc.c
index c424c0c..452193f7 100644
--- a/drivers/s390/cio/chsc.c
+++ b/drivers/s390/cio/chsc.c
@@ -1176,7 +1176,7 @@
EXPORT_SYMBOL_GPL(css_general_characteristics);
EXPORT_SYMBOL_GPL(css_chsc_characteristics);
-int chsc_sstpc(void *page, unsigned int op, u16 ctrl)
+int chsc_sstpc(void *page, unsigned int op, u16 ctrl, u64 *clock_delta)
{
struct {
struct chsc_header request;
@@ -1186,7 +1186,9 @@
unsigned int ctrl : 16;
unsigned int rsvd2[5];
struct chsc_header response;
- unsigned int rsvd3[7];
+ unsigned int rsvd3[3];
+ u64 clock_delta;
+ unsigned int rsvd4[2];
} __attribute__ ((packed)) *rr;
int rc;
@@ -1200,6 +1202,8 @@
if (rc)
return -EIO;
rc = (rr->response.code == 0x0001) ? 0 : -EIO;
+ if (clock_delta)
+ *clock_delta = rr->clock_delta;
return rc;
}