According to PLIC specification (chapter 5), there
is only one case, when interrupt is claimed. Fix
PLIC controller to match this behavior.

Signed-off-by: Sergey Makarov <s.makarov@syntacore.com>
---
 hw/intc/sifive_plic.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/hw/intc/sifive_plic.c b/hw/intc/sifive_plic.c
index 3f3ee96ebc..deec162630 100644
--- a/hw/intc/sifive_plic.c
+++ b/hw/intc/sifive_plic.c
@@ -354,8 +354,10 @@ static void sifive_plic_irq_request(void *opaque, int irq, int level)
 {
     SiFivePLICState *s = opaque;
 
-    sifive_plic_set_pending(s, irq, level > 0);
-    sifive_plic_update(s);
+    if (level > 0) {
+        sifive_plic_set_pending(s, irq, true);
+        sifive_plic_update(s);
+    }
 }
 
 static void sifive_plic_realize(DeviceState *dev, Error **errp)
-- 
2.34.1