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
---
 hw/intc/gicv3_internal.h |  1 +
 hw/intc/arm_gicv3_its.c  | 11 +++++++++++
 hw/intc/trace-events     |  1 +
 3 files changed, 13 insertions(+)

diff --git a/hw/intc/gicv3_internal.h b/hw/intc/gicv3_internal.h
index c1467ce7263..ef1d75b3cf4 100644
--- a/hw/intc/gicv3_internal.h
+++ b/hw/intc/gicv3_internal.h
@@ -330,6 +330,7 @@ FIELD(GITS_TYPER, CIL, 36, 1)
 #define GITS_CMD_MOVALL           0x0E
 #define GITS_CMD_DISCARD          0x0F
 #define GITS_CMD_VMOVP            0x22
+#define GITS_CMD_VSYNC            0x25
 #define GITS_CMD_VMAPP            0x29
 #define GITS_CMD_VMAPTI           0x2A
 #define GITS_CMD_VMAPI            0x2B
diff --git a/hw/intc/arm_gicv3_its.c b/hw/intc/arm_gicv3_its.c
index 8bc93295fb5..a3f5bac5513 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;
diff --git a/hw/intc/trace-events b/hw/intc/trace-events
index a2dd1bdb6c3..b9efe14c690 100644
--- a/hw/intc/trace-events
+++ b/hw/intc/trace-events
@@ -191,6 +191,7 @@ gicv3_its_cmd_vmapi(uint32_t devid, uint32_t eventid, uint32_t vpeid, uint32_t d
 gicv3_its_cmd_vmapti(uint32_t devid, uint32_t eventid, uint32_t vpeid, uint32_t vintid, uint32_t doorbell) "GICv3 ITS: command VMAPI DeviceID 0x%x EventID 0x%x vPEID 0x%x vINTID 0x%x Dbell_pINTID 0x%x"
 gicv3_its_cmd_vmapp(uint32_t vpeid, uint64_t rdbase, int valid, uint64_t vptaddr, uint32_t vptsize) "GICv3 ITS: command VMAPP vPEID 0x%x RDbase 0x%" PRIx64 " V %d VPT_addr 0x%" PRIx64 " VPT_size 0x%x"
 gicv3_its_cmd_vmovp(uint32_t vpeid, uint64_t rdbase) "GICv3 ITS: command VMOVP vPEID 0x%x RDbase 0x%" PRIx64
+gicv3_its_cmd_vsync(void) "GICv3 ITS: command VSYNC"
 gicv3_its_cmd_unknown(unsigned cmd) "GICv3 ITS: unknown command 0x%x"
 gicv3_its_cte_read(uint32_t icid, int valid, uint32_t rdbase) "GICv3 ITS: Collection Table read for ICID 0x%x: valid %d RDBase 0x%x"
 gicv3_its_cte_write(uint32_t icid, int valid, uint32_t rdbase) "GICv3 ITS: Collection Table write for ICID 0x%x: valid %d RDBase 0x%x"
-- 
2.25.1