diff mbox

[v15,02/15] hw/ptimer: Fix counter - 1 returned by ptimer_get_count for the active timer

Message ID 2592778c5f9be74a63c50647075843f13e6e24f6.1469110137.git.digetx@gmail.com
State New
Headers show

Commit Message

Dmitry Osipenko July 21, 2016, 2:31 p.m. UTC 
Due to rounding down performed by ptimer_get_count, it returns counter - 1 for
the enabled timer. That's incorrect because counter should decrement only after
period been expired, not before. I.e. if running timer has been loaded with
value X, then timer counter should stay with X until period expired.
Fix this by adding 1 to the counter value.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
---
 hw/core/ptimer.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)
diff mbox

Patch

diff --git a/hw/core/ptimer.c b/hw/core/ptimer.c
index 9dc2bb0..461b91c 100644
--- a/hw/core/ptimer.c
+++ b/hw/core/ptimer.c
@@ -89,6 +89,7 @@  uint64_t ptimer_get_count(ptimer_state *s)
     if (s->enabled) {
         int64_t now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
         int64_t next = s->next_event;
+        int64_t last = s->last_event;
         bool expired = (now - next >= 0);
         bool oneshot = (s->enabled == 2);
 
@@ -97,6 +98,8 @@  uint64_t ptimer_get_count(ptimer_state *s)
             /* Prevent timer underflowing if it should already have
                triggered.  */
             counter = 1;
+        } else if (now == last) {
+            counter = s->delta;
         } else {
             uint64_t rem;
             uint64_t div;
@@ -139,7 +142,7 @@  uint64_t ptimer_get_count(ptimer_state *s)
                 if ((uint32_t)(period_frac << shift))
                     div += 1;
             }
-            counter = rem / div;
+            counter = rem / div + 1;
         }
     } else {
         counter = s->delta;