fdt adds Extend I/O Interrupt Controller,
we use 'loongson,ls2k2000-eiointc'.

See:
https://github.com/torvalds/linux/blob/v6.7/drivers/irqchip/irq-loongson-eiointc.c
https://lore.kernel.org/r/764e02d924094580ac0f1d15535f4b98308705c6.1683279769.git.zhoubinbin@loongson.cn

Signed-off-by: Song Gao <gaosong@loongson.cn>
---
 include/hw/intc/loongarch_extioi.h |  1 +
 hw/loongarch/virt.c                | 30 +++++++++++++++++++++++++++++-
 2 files changed, 30 insertions(+), 1 deletion(-)

diff --git a/include/hw/intc/loongarch_extioi.h b/include/hw/intc/loongarch_extioi.h
index a0a46b888c..410c6e1121 100644
--- a/include/hw/intc/loongarch_extioi.h
+++ b/include/hw/intc/loongarch_extioi.h
@@ -39,6 +39,7 @@
 #define EXTIOI_COREISR_END           (0xB20 - APIC_OFFSET)
 #define EXTIOI_COREMAP_START         (0xC00 - APIC_OFFSET)
 #define EXTIOI_COREMAP_END           (0xD00 - APIC_OFFSET)
+#define EXTIOI_SIZE                  0x800
 
 typedef struct ExtIOICore {
     uint32_t coreisr[EXTIOI_IRQS_GROUP_COUNT];
diff --git a/hw/loongarch/virt.c b/hw/loongarch/virt.c
index a8374c35a4..4091a14080 100644
--- a/hw/loongarch/virt.c
+++ b/hw/loongarch/virt.c
@@ -100,6 +100,31 @@ static void fdt_add_cpuic_node(LoongArchMachineState *lams,
     g_free(nodename);
 }
 
+static void fdt_add_eiointc_node(LoongArchMachineState *lams,
+                                  uint32_t *cpuintc_phandle,
+                                  uint32_t *eiointc_phandle)
+{
+    MachineState *ms = MACHINE(lams);
+    char *nodename;
+    hwaddr extioi_base = APIC_BASE;
+    hwaddr extioi_size = EXTIOI_SIZE;
+
+    *eiointc_phandle = qemu_fdt_alloc_phandle(ms->fdt);
+    nodename = g_strdup_printf("/eiointc@%" PRIx64, extioi_base);
+    qemu_fdt_add_subnode(ms->fdt, nodename);
+    qemu_fdt_setprop_cell(ms->fdt, nodename, "phandle", *eiointc_phandle);
+    qemu_fdt_setprop_string(ms->fdt, nodename, "compatible",
+                            "loongson,ls2k2000-eiointc");
+    qemu_fdt_setprop(ms->fdt, nodename, "interrupt-controller", NULL, 0);
+    qemu_fdt_setprop_cell(ms->fdt, nodename, "#interrupt-cells", 1);
+    qemu_fdt_setprop_cell(ms->fdt, nodename, "interrupt-parent",
+                          *cpuintc_phandle);
+    qemu_fdt_setprop_cell(ms->fdt, nodename, "interrupts", 3);
+    qemu_fdt_setprop_cells(ms->fdt, nodename, "reg", 0x0,
+                           extioi_base, 0x0, extioi_size);
+    g_free(nodename);
+}
+
 static void fdt_add_flash_node(LoongArchMachineState *lams)
 {
     MachineState *ms = MACHINE(lams);
@@ -508,7 +533,7 @@ static void loongarch_irq_init(LoongArchMachineState *lams)
     CPULoongArchState *env;
     CPUState *cpu_state;
     int cpu, pin, i, start, num;
-    uint32_t cpuintc_phandle;
+    uint32_t cpuintc_phandle, eiointc_phandle;
 
     /*
      * The connection of interrupts:
@@ -577,6 +602,9 @@ static void loongarch_irq_init(LoongArchMachineState *lams)
         }
     }
 
+    /* Add Extend I/O Interrupt Controller node */
+    fdt_add_eiointc_node(lams, &cpuintc_phandle, &eiointc_phandle);
+
     pch_pic = qdev_new(TYPE_LOONGARCH_PCH_PIC);
     num = VIRT_PCH_PIC_IRQ_NUM;
     qdev_prop_set_uint32(pch_pic, "pch_pic_irq_num", num);
-- 
2.25.1