hw/intc: Don't clear pending bits on IRQ lowering

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>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20240918140229.124329-3-s.makarov@syntacore.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
(cherry picked from commit a84be2baa9eca8bc500f866ad943b8f63dc99adf)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>

diff --git a/hw/intc/sifive_plic.c b/hw/intc/sifive_plic.c
index e559f118052ae80639cde322166c2045f0738367..ca4c2de4949bf3efb50f30bdcc54666b25eb65dc 100644 (file)
--- a/hw/intc/sifive_plic.c
+++ b/hw/intc/sifive_plic.c
@@ -349,8 +349,10 @@ 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)