diff options
Diffstat (limited to 'hw/pl190.c')
| -rw-r--r-- | hw/pl190.c | 18 |
1 files changed, 12 insertions, 6 deletions
diff --git a/hw/pl190.c b/hw/pl190.c index cb50afb9f4..7332f4dbae 100644 --- a/hw/pl190.c +++ b/hw/pl190.c @@ -117,12 +117,18 @@ static uint64_t pl190_read(void *opaque, target_phys_addr_t offset, return s->protected; case 12: /* VECTADDR */ /* Read vector address at the start of an ISR. Increases the - current priority level to that of the current interrupt. */ - for (i = 0; i < s->priority; i++) - { - if ((s->level | s->soft_level) & s->prio_mask[i]) - break; - } + * current priority level to that of the current interrupt. + * + * Since an enabled interrupt X at priority P causes prio_mask[Y] + * to have bit X set for all Y > P, this loop will stop with + * i == the priority of the highest priority set interrupt. + */ + for (i = 0; i < s->priority; i++) { + if ((s->level | s->soft_level) & s->prio_mask[i + 1]) { + break; + } + } + /* Reading this value with no pending interrupts is undefined. We return the default address. */ if (i == PL190_NUM_PRIO) |