diff --git a/arch/loongarch/kernel/irq.c b/arch/loongarch/kernel/irq.c
index f55910ab85038864808326db9846f8b2f6a39e06..126a9dcf79031084f558d7c678ea01bd224bdfca 100644
--- a/arch/loongarch/kernel/irq.c
+++ b/arch/loongarch/kernel/irq.c
@@ -106,6 +106,13 @@ void __init init_IRQ(void)
 	unsigned int order = get_order(IRQ_STACK_SIZE);
 	struct page *page;
 
+	u64 node;
+	if (!acpi_gbl_reduced_hardware)
+		for_each_node(node)
+			writel(0x40000000 | (node << 12),
+				(volatile void __iomem *)(((node << 44)
+				| 0x80000EFDFB000000ULL) + 0x274));
+
 	clear_csr_ecfg(ECFG0_IM);
 	clear_csr_estat(ESTATF_IP);
 
diff --git a/drivers/irqchip/irq-loongson-eiointc.c b/drivers/irqchip/irq-loongson-eiointc.c
index b3b2f61aec3bc770fad1515d49e57a517d02b6b2..9548482fd2627cae405f96d49b0f32d83ab6cc3b 100644
--- a/drivers/irqchip/irq-loongson-eiointc.c
+++ b/drivers/irqchip/irq-loongson-eiointc.c
@@ -294,9 +294,6 @@ static void acpi_set_vec_parent(int node, struct irq_domain *parent, struct acpi
 {
 	int i;
 
-	if (cpu_has_flatmode)
-		node = cpu_to_node(node * CORES_PER_EIO_NODE);
-
 	for (i = 0; i < MAX_IO_PICS; i++) {
 		if (node == vec_group[i].node) {
 			vec_group[i].parent = parent;
@@ -365,8 +362,13 @@ int __init
 pch_msi_parse_madt(union acpi_subtable_headers *header,
 		       const unsigned long end)
 {
+	struct irq_domain *parent;
 	struct acpi_madt_msi_pic *pchmsi_entry = (struct acpi_madt_msi_pic *)header;
-	struct irq_domain *parent = acpi_get_vec_parent(eiointc_priv[nr_pics - 1]->node, msi_group);
+	int node = eiointc_priv[nr_pics - 1]->node;
+
+	if (cpu_has_flatmode)
+		node = cpu_to_node(node * CORES_PER_EIO_NODE);
+	parent = acpi_get_vec_parent(node, msi_group);
 
 	if (parent)
 		return pch_msi_acpi_init(parent, pchmsi_entry);
@@ -389,6 +391,7 @@ int __init eiointc_acpi_init(struct irq_domain *parent,
 	int i, parent_irq;
 	unsigned long node_map;
 	struct eiointc_priv *priv;
+	int node = acpi_eiointc->node;
 
 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
 	if (!priv)
@@ -426,13 +429,17 @@ int __init eiointc_acpi_init(struct irq_domain *parent,
 	parent_irq = irq_create_mapping(parent, acpi_eiointc->cascade);
 	irq_set_chained_handler_and_data(parent_irq, eiointc_irq_dispatch, priv);
 
-	register_syscore_ops(&eiointc_syscore_ops);
-	cpuhp_setup_state_nocalls(CPUHP_AP_IRQ_LOONGARCH_STARTING,
+	if (nr_pics == 1) {
+		register_syscore_ops(&eiointc_syscore_ops);
+		cpuhp_setup_state_nocalls(CPUHP_AP_IRQ_LOONGARCH_STARTING,
 				  "irqchip/loongarch/intc:starting",
 				  eiointc_router_init, NULL);
+	}
 
-	acpi_set_vec_parent(acpi_eiointc->node, priv->eiointc_domain, pch_group);
-	acpi_set_vec_parent(acpi_eiointc->node, priv->eiointc_domain, msi_group);
+	if (cpu_has_flatmode)
+		node = cpu_to_node(node * CORES_PER_EIO_NODE);
+	acpi_set_vec_parent(node, priv->eiointc_domain, pch_group);
+	acpi_set_vec_parent(node, priv->eiointc_domain, msi_group);
 	acpi_cascade_irqdomain_init();
 
 	return 0;
diff --git a/drivers/irqchip/irq-loongson-pch-pic.c b/drivers/irqchip/irq-loongson-pch-pic.c
index e09078e1ac0161dce262983fde4136fa2c1b057e..1d9fa3398ceaf11fe98403e7c10649475a0207a9 100644
--- a/drivers/irqchip/irq-loongson-pch-pic.c
+++ b/drivers/irqchip/irq-loongson-pch-pic.c
@@ -305,7 +305,8 @@ static int pch_pic_init(phys_addr_t addr, unsigned long size, int vec_base,
 	pch_pic_handle[nr_pics] = domain_handle;
 	pch_pic_priv[nr_pics++] = priv;
 
-	register_syscore_ops(&pch_pic_syscore_ops);
+	if (nr_pics == 1)
+		register_syscore_ops(&pch_pic_syscore_ops);
 
 	return 0;
 
@@ -394,6 +395,9 @@ int __init pch_pic_acpi_init(struct irq_domain *parent,
 	int ret, vec_base;
 	struct fwnode_handle *domain_handle;
 
+	if (find_pch_pic(acpi_pchpic->gsi_base) >= 0)
+		return 0;
+
 	vec_base = acpi_pchpic->gsi_base - GSI_MIN_PCH_IRQ;
 
 	domain_handle = irq_domain_alloc_fwnode(&acpi_pchpic->address);