diff --git a/hw/cxl/cxl-device-utils.c b/hw/cxl/cxl-device-utils.c
index 035d034f6d..52ad1e4c3f 100644
--- a/hw/cxl/cxl-device-utils.c
+++ b/hw/cxl/cxl-device-utils.c
@@ -352,10 +352,8 @@ static void device_reg_init_common(CXLDeviceState *cxl_dstate)
     }
 }
 
-static void mailbox_reg_init_common(CXLDeviceState *cxl_dstate)
+static void mailbox_reg_init_common(CXLDeviceState *cxl_dstate, int msi_n)
 {
-    const uint8_t msi_n = 9;
-
     /* 2048 payload size */
     ARRAY_FIELD_DP32(cxl_dstate->mbox_reg_state32, CXL_DEV_MAILBOX_CAP,
                      PAYLOAD_SIZE, CXL_MAILBOX_PAYLOAD_SHIFT);
@@ -382,7 +380,7 @@ static void memdev_reg_init_common(CXLDeviceState *cxl_dstate)
     cxl_dstate->memdev_status = memdev_status_reg;
 }
 
-void cxl_device_register_init_t3(CXLType3Dev *ct3d)
+void cxl_device_register_init_t3(CXLType3Dev *ct3d, int msi_n)
 {
     CXLDeviceState *cxl_dstate = &ct3d->cxl_dstate;
     uint64_t *cap_h = cxl_dstate->caps_reg_state64;
@@ -398,7 +396,7 @@ void cxl_device_register_init_t3(CXLType3Dev *ct3d)
     device_reg_init_common(cxl_dstate);
 
     cxl_device_cap_init(cxl_dstate, MAILBOX, 2, CXL_DEV_MAILBOX_VERSION);
-    mailbox_reg_init_common(cxl_dstate);
+    mailbox_reg_init_common(cxl_dstate, msi_n);
 
     cxl_device_cap_init(cxl_dstate, MEMORY_DEVICE, 0x4000,
         CXL_MEM_DEV_STATUS_VERSION);
@@ -408,7 +406,7 @@ void cxl_device_register_init_t3(CXLType3Dev *ct3d)
                               CXL_MAILBOX_MAX_PAYLOAD_SIZE);
 }
 
-void cxl_device_register_init_swcci(CSWMBCCIDev *sw)
+void cxl_device_register_init_swcci(CSWMBCCIDev *sw, int msi_n)
 {
     CXLDeviceState *cxl_dstate = &sw->cxl_dstate;
     uint64_t *cap_h = cxl_dstate->caps_reg_state64;
@@ -423,7 +421,7 @@ void cxl_device_register_init_swcci(CSWMBCCIDev *sw)
     device_reg_init_common(cxl_dstate);
 
     cxl_device_cap_init(cxl_dstate, MAILBOX, 2, 1);
-    mailbox_reg_init_common(cxl_dstate);
+    mailbox_reg_init_common(cxl_dstate, msi_n);
 
     cxl_device_cap_init(cxl_dstate, MEMORY_DEVICE, 0x4000, 1);
     memdev_reg_init_common(cxl_dstate);
diff --git a/hw/cxl/switch-mailbox-cci.c b/hw/cxl/switch-mailbox-cci.c
index 65cdac6cc1..833b824619 100644
--- a/hw/cxl/switch-mailbox-cci.c
+++ b/hw/cxl/switch-mailbox-cci.c
@@ -17,10 +17,12 @@
 #include "hw/qdev-properties.h"
 #include "hw/cxl/cxl.h"
 
+#define CXL_SWCCI_MSIX_MBOX 3
+
 static void cswmbcci_reset(DeviceState *dev)
 {
     CSWMBCCIDev *cswmb = CXL_SWITCH_MAILBOX_CCI(dev);
-    cxl_device_register_init_swcci(cswmb);
+    cxl_device_register_init_swcci(cswmb, CXL_SWCCI_MSIX_MBOX);
 }
 
 static void cswbcci_realize(PCIDevice *pci_dev, Error **errp)
diff --git a/hw/mem/cxl_type3.c b/hw/mem/cxl_type3.c
index 0ae1704a34..ebc0ec536e 100644
--- a/hw/mem/cxl_type3.c
+++ b/hw/mem/cxl_type3.c
@@ -30,6 +30,14 @@
 #include "hw/cxl/cxl.h"
 #include "hw/pci/msix.h"
 
+/* type3 device private */
+enum CXL_T3_MSIX_VECTOR {
+    CXL_T3_MSIX_PCIE_DOE_TABLE_ACCESS = 0,
+    CXL_T3_MSIX_EVENT_START = 2,
+    CXL_T3_MSIX_MBOX = CXL_T3_MSIX_EVENT_START + CXL_EVENT_TYPE_MAX,
+    CXL_T3_MSIX_VECTOR_NR
+};
+
 #define DWORD_BYTE 4
 #define CXL_CAPACITY_MULTIPLIER   (256 * MiB)
 
@@ -843,7 +851,6 @@ static void ct3_realize(PCIDevice *pci_dev, Error **errp)
     ComponentRegisters *regs = &cxl_cstate->crb;
     MemoryRegion *mr = &regs->component_registers;
     uint8_t *pci_conf = pci_dev->config;
-    unsigned short msix_num = 10;
     int i, rc;
     uint16_t count;
 
@@ -884,16 +891,17 @@ static void ct3_realize(PCIDevice *pci_dev, Error **errp)
                      &ct3d->cxl_dstate.device_registers);
 
     /* MSI(-X) Initialization */
-    rc = msix_init_exclusive_bar(pci_dev, msix_num, 4, NULL);
+    rc = msix_init_exclusive_bar(pci_dev, CXL_T3_MSIX_VECTOR_NR, 4, NULL);
     if (rc) {
         goto err_address_space_free;
     }
-    for (i = 0; i < msix_num; i++) {
+    for (i = 0; i < CXL_T3_MSIX_VECTOR_NR; i++) {
         msix_vector_use(pci_dev, i);
     }
 
     /* DOE Initialization */
-    pcie_doe_init(pci_dev, &ct3d->doe_cdat, 0x190, doe_cdat_prot, true, 0);
+    pcie_doe_init(pci_dev, &ct3d->doe_cdat, 0x190, doe_cdat_prot, true,
+                  CXL_T3_MSIX_PCIE_DOE_TABLE_ACCESS);
 
     cxl_cstate->cdat.build_cdat_table = ct3_build_cdat_table;
     cxl_cstate->cdat.free_cdat_table = ct3_free_cdat_table;
@@ -908,7 +916,7 @@ static void ct3_realize(PCIDevice *pci_dev, Error **errp)
     if (rc) {
         goto err_release_cdat;
     }
-    cxl_event_init(&ct3d->cxl_dstate, 2);
+    cxl_event_init(&ct3d->cxl_dstate, CXL_T3_MSIX_EVENT_START);
 
     /* Set default value for patrol scrub attributes */
     ct3d->patrol_scrub_attrs.scrub_cycle_cap =
@@ -1202,7 +1210,7 @@ static void ct3d_reset(DeviceState *dev)
 
     pcie_cap_fill_link_ep_usp(PCI_DEVICE(dev), ct3d->width, ct3d->speed);
     cxl_component_register_init_common(reg_state, write_msk, CXL2_TYPE3_DEVICE);
-    cxl_device_register_init_t3(ct3d);
+    cxl_device_register_init_t3(ct3d, CXL_T3_MSIX_MBOX);
 
     /*
      * Bring up an endpoint to target with MCTP over VDM.
diff --git a/include/hw/cxl/cxl_device.h b/include/hw/cxl/cxl_device.h
index 561b375dc8..3a0ee7e8e7 100644
--- a/include/hw/cxl/cxl_device.h
+++ b/include/hw/cxl/cxl_device.h
@@ -264,8 +264,8 @@ void cxl_device_register_block_init(Object *obj, CXLDeviceState *dev,
 typedef struct CXLType3Dev CXLType3Dev;
 typedef struct CSWMBCCIDev CSWMBCCIDev;
 /* Set up default values for the register block */
-void cxl_device_register_init_t3(CXLType3Dev *ct3d);
-void cxl_device_register_init_swcci(CSWMBCCIDev *sw);
+void cxl_device_register_init_t3(CXLType3Dev *ct3d, int msi_n);
+void cxl_device_register_init_swcci(CSWMBCCIDev *sw, int msi_n);
 
 /*
  * CXL r3.1 Section 8.2.8.1: CXL Device Capabilities Array Register