irqchip/loongson-eiointc: Add DT init support

Add EIOINTC irqchip DT support, which is needed for Loongson chips
based on DT and supporting EIOINTC, such as the Loongson-2K0500 SOC.

Signed-off-by: Binbin Zhou <[email protected]>
Signed-off-by: Marc Zyngier <[email protected]>
Link: https://lore.kernel.org/r/764e02d924094580ac0f1d15535f4b98308705c6.1683279769.git.zhoubinbin@loongson.cn

Author: AaronDot

drivers/irqchip/irq-loongson-eiointc.c

@@ -36,6 +36,7 @@ static int nr_pics;
 
 struct eiointc_priv {
 	u32			node;
+	u32			vec_count;
 	nodemask_t		node_map;
 	cpumask_t		cpuspan_map;
 	struct fwnode_handle	*domain_handle;
@@ -153,18 +154,18 @@ static int eiointc_router_init(unsigned int cpu)
 	if ((cpu_logical_map(cpu) % CORES_PER_EIO_NODE) == 0) {
 		eiointc_enable();
 
-		for (i = 0; i < VEC_COUNT / 32; i++) {
+		for (i = 0; i < eiointc_priv[0]->vec_count / 32; i++) {
 			data = (((1 << (i * 2 + 1)) << 16) | (1 << (i * 2)));
 			iocsr_write32(data, EIOINTC_REG_NODEMAP + i * 4);
 		}
 
-		for (i = 0; i < VEC_COUNT / 32 / 4; i++) {
+		for (i = 0; i < eiointc_priv[0]->vec_count / 32 / 4; i++) {
 			bit = BIT(1 + index); /* Route to IP[1 + index] */
 			data = bit | (bit << 8) | (bit << 16) | (bit << 24);
 			iocsr_write32(data, EIOINTC_REG_IPMAP + i * 4);
 		}
 
-		for (i = 0; i < VEC_COUNT / 4; i++) {
+		for (i = 0; i < eiointc_priv[0]->vec_count / 4; i++) {
 			/* Route to Node-0 Core-0 */
 			if (index == 0)
 				bit = BIT(cpu_logical_map(0));
@@ -175,7 +176,7 @@ static int eiointc_router_init(unsigned int cpu)
 			iocsr_write32(data, EIOINTC_REG_ROUTE + i * 4);
 		}
 
-		for (i = 0; i < VEC_COUNT / 32; i++) {
+		for (i = 0; i < eiointc_priv[0]->vec_count / 32; i++) {
 			data = 0xffffffff;
 			iocsr_write32(data, EIOINTC_REG_ENABLE + i * 4);
 			iocsr_write32(data, EIOINTC_REG_BOUNCE + i * 4);
@@ -195,7 +196,7 @@ static void eiointc_irq_dispatch(struct irq_desc *desc)
 
 	chained_irq_enter(chip, desc);
 
-	for (i = 0; i < VEC_REG_COUNT; i++) {
+	for (i = 0; i < eiointc_priv[0]->vec_count / VEC_COUNT_PER_REG; i++) {
 		pending = iocsr_read64(EIOINTC_REG_ISR + (i << 3));
 		iocsr_write64(pending, EIOINTC_REG_ISR + (i << 3));
 		while (pending) {
@@ -310,7 +311,7 @@ static void eiointc_resume(void)
 	eiointc_router_init(0);
 
 	for (i = 0; i < nr_pics; i++) {
-		for (j = 0; j < VEC_COUNT; j++) {
+		for (j = 0; j < eiointc_priv[0]->vec_count; j++) {
 			desc = irq_resolve_mapping(eiointc_priv[i]->eiointc_domain, j);
 			if (desc && desc->handle_irq && desc->handle_irq != handle_bad_irq) {
 				raw_spin_lock(&desc->lock);
@@ -375,11 +376,47 @@ static int __init acpi_cascade_irqdomain_init(void)
 	return 0;
 }
 
+static int __init eiointc_init(struct eiointc_priv *priv, int parent_irq,
+			       u64 node_map)
+{
+	int i;
+
+	node_map = node_map ? node_map : -1ULL;
+	for_each_possible_cpu(i) {
+		if (node_map & (1ULL << (cpu_to_eio_node(i)))) {
+			node_set(cpu_to_eio_node(i), priv->node_map);
+			cpumask_or(&priv->cpuspan_map, &priv->cpuspan_map,
+				   cpumask_of(i));
+		}
+	}
+
+	priv->eiointc_domain = irq_domain_create_linear(priv->domain_handle,
+							priv->vec_count,
+							&eiointc_domain_ops,
+							priv);
+	if (!priv->eiointc_domain) {
+		pr_err("loongson-extioi: cannot add IRQ domain\n");
+		return -ENOMEM;
+	}
+
+	eiointc_priv[nr_pics++] = priv;
+	eiointc_router_init(0);
+	irq_set_chained_handler_and_data(parent_irq, eiointc_irq_dispatch, priv);
+
+	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);
+	}
+
+	return 0;
+}
+
 int __init eiointc_acpi_init(struct irq_domain *parent,
 				     struct acpi_madt_eio_pic *acpi_eiointc)
 {
-	int i, ret, parent_irq;
-	unsigned long node_map;
+	int parent_irq, ret;
 	struct eiointc_priv *priv;
 	int node;
 
@@ -394,45 +431,25 @@ int __init eiointc_acpi_init(struct irq_domain *parent,
 		goto out_free_priv;
 	}
 
+	priv->vec_count = VEC_COUNT;
 	priv->node = acpi_eiointc->node;
-	node_map = acpi_eiointc->node_map ? : -1ULL;
-
-	for_each_possible_cpu(i) {
-		if (node_map & (1ULL << cpu_to_eio_node(i))) {
-			node_set(cpu_to_eio_node(i), priv->node_map);
-			cpumask_or(&priv->cpuspan_map, &priv->cpuspan_map, cpumask_of(i));
-		}
-	}
-
-	/* Setup IRQ domain */
-	priv->eiointc_domain = irq_domain_create_linear(priv->domain_handle, VEC_COUNT,
-					&eiointc_domain_ops, priv);
-	if (!priv->eiointc_domain) {
-		pr_err("loongson-eiointc: cannot add IRQ domain\n");
-		goto out_free_handle;
-	}
-
-	eiointc_priv[nr_pics++] = priv;
-
-	eiointc_router_init(0);
 
 	parent_irq = irq_create_mapping(parent, acpi_eiointc->cascade);
-	irq_set_chained_handler_and_data(parent_irq, eiointc_irq_dispatch, priv);
 
-	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);
-	}
+	ret = eiointc_init(priv, parent_irq, acpi_eiointc->node_map);
+	if (ret < 0)
+		goto out_free_handle;
 
 	if (cpu_has_flatmode)
 		node = cpu_to_node(acpi_eiointc->node * CORES_PER_EIO_NODE);
 	else
 		node = acpi_eiointc->node;
 	acpi_set_vec_parent(node, priv->eiointc_domain, pch_group);
 	acpi_set_vec_parent(node, priv->eiointc_domain, msi_group);
+
 	ret = acpi_cascade_irqdomain_init();
+	if (ret < 0)
+		goto out_free_handle;
 
 	return ret;
 
@@ -444,3 +461,49 @@ int __init eiointc_acpi_init(struct irq_domain *parent,
 
 	return -ENOMEM;
 }
+
+static int __init eiointc_of_init(struct device_node *of_node,
+				  struct device_node *parent)
+{
+	int parent_irq, ret;
+	struct eiointc_priv *priv;
+
+	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	parent_irq = irq_of_parse_and_map(of_node, 0);
+	if (parent_irq <= 0) {
+		ret = -ENODEV;
+		goto out_free_priv;
+	}
+
+	ret = irq_set_handler_data(parent_irq, priv);
+	if (ret < 0)
+		goto out_free_priv;
+
+	/*
+	 * In particular, the number of devices supported by the LS2K0500
+	 * extended I/O interrupt vector is 128.
+	 */
+	if (of_device_is_compatible(of_node, "loongson,ls2k0500-eiointc"))
+		priv->vec_count = 128;
+	else
+		priv->vec_count = VEC_COUNT;
+
+	priv->node = 0;
+	priv->domain_handle = of_node_to_fwnode(of_node);
+
+	ret = eiointc_init(priv, parent_irq, 0);
+	if (ret < 0)
+		goto out_free_priv;
+
+	return 0;
+
+out_free_priv:
+	kfree(priv);
+	return ret;
+}
+
+IRQCHIP_DECLARE(loongson_ls2k0500_eiointc, "loongson,ls2k0500-eiointc", eiointc_of_init);
+IRQCHIP_DECLARE(loongson_ls2k2000_eiointc, "loongson,ls2k2000-eiointc", eiointc_of_init);