hw/intc/arm_gicv3_its: Implement VSYNC

The VSYNC command forces the ITS to synchronize all outstanding ITS
operations for the specified vPEID, so that subsequent writes to
GITS_TRANSLATER honour them.  The QEMU implementation is always in
sync, so for us this is a nop, like the existing SYNC command.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220408141550.1271295-18-peter.maydell@linaro.org

1 files changed, 11 insertions, 0 deletions

diff --git a/hw/intc/arm_gicv3_its.c b/hw/intc/arm_gicv3_its.c
index 8bc93295fb..a3f5bac551 100644
--- a/hw/intc/arm_gicv3_its.c
+++ b/hw/intc/arm_gicv3_its.c
@@ -1165,6 +1165,17 @@ static void process_cmdq(GICv3ITSState *s)
              */
             trace_gicv3_its_cmd_sync();
             break;
+        case GITS_CMD_VSYNC:
+            /*
+             * VSYNC also is a nop, because our implementation is always
+             * in sync.
+             */
+            if (!its_feature_virtual(s)) {
+                result = CMD_CONTINUE;
+                break;
+            }
+            trace_gicv3_its_cmd_vsync();
+            break;
         case GITS_CMD_MAPD:
             result = process_mapd(s, cmdpkt);
             break;