diff options
Diffstat (limited to 'target/arm/helper.c')
| -rw-r--r-- | target/arm/helper.c | 25 |
1 files changed, 21 insertions, 4 deletions
diff --git a/target/arm/helper.c b/target/arm/helper.c index ff1970981e..2746d3fdac 100644 --- a/target/arm/helper.c +++ b/target/arm/helper.c @@ -2646,11 +2646,28 @@ static void gt_recalc_timer(ARMCPU *cpu, int timeridx) gt->ctl = deposit32(gt->ctl, 2, 1, istatus); if (istatus) { - /* Next transition is when count rolls back over to zero */ - nexttick = UINT64_MAX; + /* + * Next transition is when (count - offset) rolls back over to 0. + * If offset > count then this is when count == offset; + * if offset <= count then this is when count == offset + 2^64 + * For the latter case we set nexttick to an "as far in future + * as possible" value and let the code below handle it. + */ + if (offset > count) { + nexttick = offset; + } else { + nexttick = UINT64_MAX; + } } else { - /* Next transition is when we hit cval */ - nexttick = gt->cval + offset; + /* + * Next transition is when (count - offset) == cval, i.e. + * when count == (cval + offset). + * If that would overflow, then again we set up the next interrupt + * for "as far in the future as possible" for the code below. + */ + if (uadd64_overflow(gt->cval, offset, &nexttick)) { + nexttick = UINT64_MAX; + } } /* * Note that the desired next expiry time might be beyond the |