Merge remote-tracking branch 'remotes/pmaydell/tags/pull-target-arm-20180709' into staging

target-arm queue:
 * hw/net/dp8393x: don't make prom region 'nomigrate'
 * boards.h: Remove doc comment reference to nonexistent function
 * hw/sd/omap_mmc: Split 'pseudo-reset' from 'power-on-reset'
 * target/arm: Fix do_predset for large VL
 * tcg: Restrict check_size_impl to multiples of the line size
 * target/arm: Suppress Coverity warning for PRF
 * hw/timer/cmsdk-apb-timer: fix minor corner-case bugs and
   suppress spurious warnings when running Linux's timer driver
 * hw/arm/smmu-common: Fix devfn computation in smmu_iommu_mr

# gpg: Signature made Mon 09 Jul 2018 14:53:38 BST
# gpg:                using RSA key 3C2525ED14360CDE
# gpg: Good signature from "Peter Maydell <peter.maydell@linaro.org>"
# gpg:                 aka "Peter Maydell <pmaydell@gmail.com>"
# gpg:                 aka "Peter Maydell <pmaydell@chiark.greenend.org.uk>"
# Primary key fingerprint: E1A5 C593 CD41 9DE2 8E83  15CF 3C25 25ED 1436 0CDE

* remotes/pmaydell/tags/pull-target-arm-20180709:
  hw/net/dp8393x: don't make prom region 'nomigrate'
  boards.h: Remove doc comment reference to nonexistent function
  hw/sd/omap_mmc: Split 'pseudo-reset' from 'power-on-reset'
  target/arm: Fix do_predset for large VL
  tcg: Restrict check_size_impl to multiples of the line size
  target/arm: Suppress Coverity warning for PRF
  hw/timer/cmsdk-apb-timer: run or stop timer on writes to RELOAD and VALUE
  hw/timer/cmsdk-apb-timer: Correctly identify and set one-shot mode
  hw/timer/cmsdk-apb-timer: Correct ptimer policy settings
  ptimer: Add TRIGGER_ONLY_ON_DECREMENT policy option
  hw/arm/smmu-common: Fix devfn computation in smmu_iommu_mr

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 21 insertions, 1 deletions

diff --git a/hw/core/ptimer.c b/hw/core/ptimer.c
index 7221c68a98..170fd34d8b 100644
--- a/hw/core/ptimer.c
+++ b/hw/core/ptimer.c
@@ -45,8 +45,20 @@ static void ptimer_reload(ptimer_state *s, int delta_adjust)
     uint32_t period_frac = s->period_frac;
     uint64_t period = s->period;
     uint64_t delta = s->delta;
+    bool suppress_trigger = false;
 
-    if (delta == 0 && !(s->policy_mask & PTIMER_POLICY_NO_IMMEDIATE_TRIGGER)) {
+    /*
+     * Note that if delta_adjust is 0 then we must be here because of
+     * a count register write or timer start, not because of timer expiry.
+     * In that case the policy might require us to suppress the timer trigger
+     * that we would otherwise generate for a zero delta.
+     */
+    if (delta_adjust == 0 &&
+        (s->policy_mask & PTIMER_POLICY_TRIGGER_ONLY_ON_DECREMENT)) {
+        suppress_trigger = true;
+    }
+    if (delta == 0 && !(s->policy_mask & PTIMER_POLICY_NO_IMMEDIATE_TRIGGER)
+        && !suppress_trigger) {
         ptimer_trigger(s);
     }
 
@@ -353,6 +365,14 @@ ptimer_state *ptimer_init(QEMUBH *bh, uint8_t policy_mask)
     s->bh = bh;
     s->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, ptimer_tick, s);
     s->policy_mask = policy_mask;
+
+    /*
+     * These two policies are incompatible -- trigger-on-decrement implies
+     * a timer trigger when the count becomes 0, but no-immediate-trigger
+     * implies a trigger when the count stops being 0.
+     */
+    assert(!((policy_mask & PTIMER_POLICY_TRIGGER_ONLY_ON_DECREMENT) &&
+             (policy_mask & PTIMER_POLICY_NO_IMMEDIATE_TRIGGER)));
     return s;
 }