diff --git a/hw/intc/loongarch_pch_msi.c b/hw/intc/loongarch_pch_msi.c
index b36d6d76e4..279be448d2 100644
--- a/hw/intc/loongarch_pch_msi.c
+++ b/hw/intc/loongarch_pch_msi.c
@@ -32,7 +32,7 @@ static void loongarch_msi_mem_write(void *opaque, hwaddr addr,
      */
     irq_num = (val & 0xff) - s->irq_base;
     trace_loongarch_msi_set_irq(irq_num);
-    assert(irq_num < PCH_MSI_IRQ_NUM);
+    assert(irq_num < s->irq_num);
     qemu_set_irq(s->pch_msi_irq[irq_num], 1);
 }
 
@@ -49,6 +49,22 @@ static void pch_msi_irq_handler(void *opaque, int irq, int level)
     qemu_set_irq(s->pch_msi_irq[irq], level);
 }
 
+static void loongarch_pch_msi_realize(DeviceState *dev, Error **errp)
+{
+    LoongArchPCHMSI *s = LOONGARCH_PCH_MSI(dev);
+
+    assert(s->irq_num > 0);
+
+    s->pch_msi_irq = g_malloc(sizeof(qemu_irq) * s->irq_num);
+    if (!s->pch_msi_irq) {
+        error_report("loongarch_pch_msi: fail to alloc memory");
+        exit(1);
+    }
+
+    qdev_init_gpio_out(dev, s->pch_msi_irq, s->irq_num);
+    qdev_init_gpio_in(dev, pch_msi_irq_handler, s->irq_num);
+}
+
 static void loongarch_pch_msi_init(Object *obj)
 {
     LoongArchPCHMSI *s = LOONGARCH_PCH_MSI(obj);
@@ -59,12 +75,11 @@ static void loongarch_pch_msi_init(Object *obj)
     sysbus_init_mmio(sbd, &s->msi_mmio);
     msi_nonbroken = true;
 
-    qdev_init_gpio_out(DEVICE(obj), s->pch_msi_irq, PCH_MSI_IRQ_NUM);
-    qdev_init_gpio_in(DEVICE(obj), pch_msi_irq_handler, PCH_MSI_IRQ_NUM);
 }
 
 static Property loongarch_msi_properties[] = {
     DEFINE_PROP_UINT32("msi_irq_base", LoongArchPCHMSI, irq_base, 0),
+    DEFINE_PROP_UINT32("msi_irq_num",  LoongArchPCHMSI, irq_num, 0),
     DEFINE_PROP_END_OF_LIST(),
 };
 
@@ -72,6 +87,7 @@ static void loongarch_pch_msi_class_init(ObjectClass *klass, void *data)
 {
     DeviceClass *dc = DEVICE_CLASS(klass);
 
+    dc->realize = loongarch_pch_msi_realize;
     device_class_set_props(dc, loongarch_msi_properties);
 }
 
diff --git a/hw/loongarch/virt.c b/hw/loongarch/virt.c
index 958be74fa1..3547d5f711 100644
--- a/hw/loongarch/virt.c
+++ b/hw/loongarch/virt.c
@@ -496,7 +496,7 @@ static void loongarch_irq_init(LoongArchMachineState *lams)
     LoongArchCPU *lacpu;
     CPULoongArchState *env;
     CPUState *cpu_state;
-    int cpu, pin, i;
+    int cpu, pin, i, start, num;
 
     ipi = qdev_new(TYPE_LOONGARCH_IPI);
     sysbus_realize_and_unref(SYS_BUS_DEVICE(ipi), &error_fatal);
@@ -576,14 +576,17 @@ static void loongarch_irq_init(LoongArchMachineState *lams)
     }
 
     pch_msi = qdev_new(TYPE_LOONGARCH_PCH_MSI);
-    qdev_prop_set_uint32(pch_msi, "msi_irq_base", PCH_MSI_IRQ_START);
+    start   =  PCH_PIC_IRQ_NUM;
+    num = 256 - start;
+    qdev_prop_set_uint32(pch_msi, "msi_irq_base", start);
+    qdev_prop_set_uint32(pch_msi, "msi_irq_num", num);
     d = SYS_BUS_DEVICE(pch_msi);
     sysbus_realize_and_unref(d, &error_fatal);
     sysbus_mmio_map(d, 0, VIRT_PCH_MSI_ADDR_LOW);
-    for (i = 0; i < PCH_MSI_IRQ_NUM; i++) {
+    for (i = 0; i < num; i++) {
         /* Connect 192 pch_msi irqs to extioi */
         qdev_connect_gpio_out(DEVICE(d), i,
-                              qdev_get_gpio_in(extioi, i + PCH_MSI_IRQ_START));
+                              qdev_get_gpio_in(extioi, i + start));
     }
 
     loongarch_devices_init(pch_pic, lams);
diff --git a/include/hw/intc/loongarch_pch_msi.h b/include/hw/intc/loongarch_pch_msi.h
index 6d67560dea..c5a52bc327 100644
--- a/include/hw/intc/loongarch_pch_msi.h
+++ b/include/hw/intc/loongarch_pch_msi.h
@@ -15,8 +15,9 @@ OBJECT_DECLARE_SIMPLE_TYPE(LoongArchPCHMSI, LOONGARCH_PCH_MSI)
 
 struct LoongArchPCHMSI {
     SysBusDevice parent_obj;
-    qemu_irq pch_msi_irq[PCH_MSI_IRQ_NUM];
+    qemu_irq *pch_msi_irq;
     MemoryRegion msi_mmio;
     /* irq base passed to upper extioi intc */
     unsigned int irq_base;
+    unsigned int irq_num;
 };
diff --git a/include/hw/pci-host/ls7a.h b/include/hw/pci-host/ls7a.h
index df7fa55a30..6443327bd7 100644
--- a/include/hw/pci-host/ls7a.h
+++ b/include/hw/pci-host/ls7a.h
@@ -34,7 +34,6 @@
  */
 #define PCH_PIC_IRQ_OFFSET       64
 #define VIRT_DEVICE_IRQS         16
-#define VIRT_PCI_IRQS            48
 #define VIRT_UART_IRQ            (PCH_PIC_IRQ_OFFSET + 2)
 #define VIRT_UART_BASE           0x1fe001e0
 #define VIRT_UART_SIZE           0X100
