1 files changed, 43 insertions, 1 deletions
diff --git a/hw/cxl/cxl-device-utils.c b/hw/cxl/cxl-device-utils.c
index 327949a805..eb86634250 100644
--- a/hw/cxl/cxl-device-utils.c
+++ b/hw/cxl/cxl-device-utils.c
@@ -157,7 +157,49 @@ static void mailbox_reg_write(void *opaque, hwaddr offset, uint64_t value,
 
     if (ARRAY_FIELD_EX32(cxl_dstate->mbox_reg_state32, CXL_DEV_MAILBOX_CTRL,
                          DOORBELL)) {
-        cxl_process_mailbox(cci);
+        uint64_t command_reg =
+            cxl_dstate->mbox_reg_state64[R_CXL_DEV_MAILBOX_CMD];
+        uint8_t cmd_set = FIELD_EX64(command_reg, CXL_DEV_MAILBOX_CMD,
+                                     COMMAND_SET);
+        uint8_t cmd = FIELD_EX64(command_reg, CXL_DEV_MAILBOX_CMD, COMMAND);
+        size_t len_in = FIELD_EX64(command_reg, CXL_DEV_MAILBOX_CMD, LENGTH);
+        uint8_t *pl = cxl_dstate->mbox_reg_state + A_CXL_DEV_CMD_PAYLOAD;
+        /*
+         * Copy taken to avoid need for individual command handlers to care
+         * about aliasing.
+         */
+        g_autofree uint8_t *pl_in_copy = NULL;
+        size_t len_out = 0;
+        uint64_t status_reg;
+        bool bg_started = false;
+        int rc;
+
+        pl_in_copy = g_memdup2(pl, len_in);
+        if (len_in == 0 || pl_in_copy) {
+            /* Avoid stale data  - including from earlier cmds */
+            memset(pl, 0, CXL_MAILBOX_MAX_PAYLOAD_SIZE);
+            rc = cxl_process_cci_message(cci, cmd_set, cmd, len_in, pl_in_copy,
+                                         &len_out, pl, &bg_started);
+        } else {
+            rc = CXL_MBOX_INTERNAL_ERROR;
+        }
+
+        /* Set bg and the return code */
+        status_reg = FIELD_DP64(0, CXL_DEV_MAILBOX_STS, BG_OP,
+                                bg_started ? 1 : 0);
+        status_reg = FIELD_DP64(status_reg, CXL_DEV_MAILBOX_STS, ERRNO, rc);
+        /* Set the return length */
+        command_reg = FIELD_DP64(0, CXL_DEV_MAILBOX_CMD, COMMAND_SET, cmd_set);
+        command_reg = FIELD_DP64(command_reg, CXL_DEV_MAILBOX_CMD,
+                                 COMMAND, cmd);
+        command_reg = FIELD_DP64(command_reg, CXL_DEV_MAILBOX_CMD,
+                                 LENGTH, len_out);
+
+        cxl_dstate->mbox_reg_state64[R_CXL_DEV_MAILBOX_CMD] = command_reg;
+        cxl_dstate->mbox_reg_state64[R_CXL_DEV_MAILBOX_STS] = status_reg;
+        /* Tell the host we're done */
+        ARRAY_FIELD_DP32(cxl_dstate->mbox_reg_state32, CXL_DEV_MAILBOX_CTRL,
+                         DOORBELL, 0);
     }
 }