[PATCH RFC 07/10] irqchip/loongson-htvec: Add suspend/resume support

[PATCH RFC 07/10] irqchip/loongson-htvec: Add suspend/resume support

[Jianmin Lv]

Add suspend/resume support for HTVEC irqchip, which is needed for
suspend/hibernation.

Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Jianmin Lv <lvjianmin@loongson.cn>
---
 drivers/irqchip/irq-loongson-htvec.c | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/drivers/irqchip/irq-loongson-htvec.c b/drivers/irqchip/irq-loongson-htvec.c
index 354630b..a3c60e3 100644
--- a/drivers/irqchip/irq-loongson-htvec.c
+++ b/drivers/irqchip/irq-loongson-htvec.c
@@ -16,6 +16,7 @@
 #include <linux/of_address.h>
 #include <linux/of_irq.h>
 #include <linux/of_platform.h>
+#include <linux/syscore_ops.h>
 #include "irq-loongarch-pic-common.h"
 
 /* Registers */
@@ -31,6 +32,7 @@ struct htvec {
 	struct irq_domain	*htvec_domain;
 	raw_spinlock_t		htvec_lock;
 	struct fwnode_handle	*domain_handle;
+	u32			saved_vec_en[HTVEC_MAX_PARENT_IRQ];
 };
 
 static struct htvec *htvec_priv;
@@ -158,6 +160,29 @@ static void htvec_reset(struct htvec *priv)
 	}
 }
 
+static int htvec_suspend(void)
+{
+	int i;
+
+	for (i = 0; i < htvec_priv->num_parents; i++)
+		htvec_priv->saved_vec_en[i] = readl(htvec_priv->base + HTVEC_EN_OFF + 4 * i);
+
+	return 0;
+}
+
+static void htvec_resume(void)
+{
+	int i;
+
+	for (i = 0; i < htvec_priv->num_parents; i++)
+		writel(htvec_priv->saved_vec_en[i], htvec_priv->base + HTVEC_EN_OFF + 4 * i);
+}
+
+static struct syscore_ops htvec_syscore_ops = {
+	.suspend = htvec_suspend,
+	.resume = htvec_resume,
+};
+
 static int htvec_init(phys_addr_t addr, unsigned long size,
 		int num_parents, int parent_irq[], struct fwnode_handle *domain_handle)
 {
@@ -193,6 +218,8 @@ static int htvec_init(phys_addr_t addr, unsigned long size,
 
 	register_syscore_ops(&htvec_syscore_ops);
 
+	register_syscore_ops(&htvec_syscore_ops);
+
 	return 0;
 
 iounmap_base:
-- 
1.8.3.1

[PATCH RFC 08/10] irqchip/loongson-liointc: Add ACPI init support

[Jianmin Lv]

We are preparing to add new Loongson (based on LoongArch, not compatible
with old MIPS-based Loongson) support. LoongArch use ACPI other than DT
as its boot protocol, so add ACPI init support.

LIOINTC stands for "Legacy I/O Interrupts" that described in Section
11.1 of "Loongson 3A5000 Processor Reference Manual". For more
information please refer Documentation/loongarch/irq-chip-model.rst.

Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Jianmin Lv <lvjianmin@loongson.cn>
---
 drivers/irqchip/irq-loongson-liointc.c | 215 +++++++++++++++++++++------------
 1 file changed, 136 insertions(+), 79 deletions(-)

diff --git a/drivers/irqchip/irq-loongson-liointc.c b/drivers/irqchip/irq-loongson-liointc.c
index 649c583..8b6487f 100644
--- a/drivers/irqchip/irq-loongson-liointc.c
+++ b/drivers/irqchip/irq-loongson-liointc.c
@@ -16,10 +16,14 @@
 #include <linux/smp.h>
 #include <linux/irqchip/chained_irq.h>
 
+#ifdef CONFIG_MIPS
 #include <loongson.h>
+#else
+#include <asm/loongson.h>
+#endif
 
 #define LIOINTC_CHIP_IRQ	32
-#define LIOINTC_NUM_PARENT 4
+#define LIOINTC_NUM_PARENT	4
 #define LIOINTC_NUM_CORES	4
 
 #define LIOINTC_INTC_CHIP_START	0x20
@@ -41,6 +45,7 @@ struct liointc_handler_data {
 };
 
 struct liointc_priv {
+	struct fwnode_handle		*domain_handle;
 	struct irq_chip_generic		*gc;
 	struct liointc_handler_data	handler[LIOINTC_NUM_PARENT];
 	void __iomem			*core_isr[LIOINTC_NUM_CORES];
@@ -53,7 +58,7 @@ static void liointc_chained_handle_irq(struct irq_desc *desc)
 	struct liointc_handler_data *handler = irq_desc_get_handler_data(desc);
 	struct irq_chip *chip = irq_desc_get_chip(desc);
 	struct irq_chip_generic *gc = handler->priv->gc;
-	int core = get_ebase_cpunum() % LIOINTC_NUM_CORES;
+	int core = cpu_logical_map(smp_processor_id()) % LIOINTC_NUM_CORES;
 	u32 pending;
 
 	chained_irq_enter(chip, desc);
@@ -143,97 +148,62 @@ static void liointc_resume(struct irq_chip_generic *gc)
 	irq_gc_unlock_irqrestore(gc, flags);
 }
 
-static const char * const parent_names[] = {"int0", "int1", "int2", "int3"};
-static const char * const core_reg_names[] = {"isr0", "isr1", "isr2", "isr3"};
+static int parent_irq[LIOINTC_NUM_PARENT];
+static u32 parent_int_map[LIOINTC_NUM_PARENT];
+static const char *const parent_names[] = {"int0", "int1", "int2", "int3"};
+static const char *const core_reg_names[] = {"isr0", "isr1", "isr2", "isr3"};
 
-static void __iomem *liointc_get_reg_byname(struct device_node *node,
-						const char *name)
-{
-	int index = of_property_match_string(node, "reg-names", name);
-
-	if (index < 0)
-		return NULL;
-
-	return of_iomap(node, index);
-}
-
-static int __init liointc_of_init(struct device_node *node,
-				  struct device_node *parent)
+static int liointc_init(phys_addr_t addr, unsigned long size, int revision,
+		struct fwnode_handle *domain_handle, struct device_node *node)
 {
+	int i, err;
+	void __iomem *base;
+	struct irq_chip_type *ct;
 	struct irq_chip_generic *gc;
 	struct irq_domain *domain;
-	struct irq_chip_type *ct;
 	struct liointc_priv *priv;
-	void __iomem *base;
-	u32 of_parent_int_map[LIOINTC_NUM_PARENT];
-	int parent_irq[LIOINTC_NUM_PARENT];
-	bool have_parent = FALSE;
-	int sz, i, err = 0;
 
 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
 	if (!priv)
 		return -ENOMEM;
 
-	if (of_device_is_compatible(node, "loongson,liointc-2.0")) {
-		base = liointc_get_reg_byname(node, "main");
-		if (!base) {
-			err = -ENODEV;
-			goto out_free_priv;
-		}
+	base = ioremap(addr, size);
+	if (!base)
+		goto out_free_priv;
 
-		for (i = 0; i < LIOINTC_NUM_CORES; i++)
-			priv->core_isr[i] = liointc_get_reg_byname(node, core_reg_names[i]);
-		if (!priv->core_isr[0]) {
-			err = -ENODEV;
-			goto out_iounmap_base;
-		}
-	} else {
-		base = of_iomap(node, 0);
-		if (!base) {
-			err = -ENODEV;
-			goto out_free_priv;
-		}
+	priv->domain_handle = domain_handle;
 
-		for (i = 0; i < LIOINTC_NUM_CORES; i++)
-			priv->core_isr[i] = base + LIOINTC_REG_INTC_STATUS;
-	}
+	for (i = 0; i < LIOINTC_NUM_CORES; i++)
+		priv->core_isr[i] = base + LIOINTC_REG_INTC_STATUS;
 
-	for (i = 0; i < LIOINTC_NUM_PARENT; i++) {
-		parent_irq[i] = of_irq_get_byname(node, parent_names[i]);
-		if (parent_irq[i] > 0)
-			have_parent = TRUE;
-	}
-	if (!have_parent) {
-		err = -ENODEV;
-		goto out_iounmap_isr;
-	}
+	for (i = 0; i < LIOINTC_NUM_PARENT; i++)
+		priv->handler[i].parent_int_map = parent_int_map[i];
 
-	sz = of_property_read_variable_u32_array(node,
-						"loongson,parent_int_map",
-						&of_parent_int_map[0],
-						LIOINTC_NUM_PARENT,
-						LIOINTC_NUM_PARENT);
-	if (sz < 4) {
-		pr_err("loongson-liointc: No parent_int_map\n");
-		err = -ENODEV;
-		goto out_iounmap_isr;
-	}
+#ifdef CONFIG_OF
+	if (revision > 1) {
+		for (i = 0; i < LIOINTC_NUM_CORES; i++) {
+			int index = of_property_match_string(node,
+					"reg-names", core_reg_names[i]);
 
-	for (i = 0; i < LIOINTC_NUM_PARENT; i++)
-		priv->handler[i].parent_int_map = of_parent_int_map[i];
+			if (index < 0)
+				return -EINVAL;
+
+			priv->core_isr[i] = of_iomap(node, index);
+		}
+	}
+#endif
 
 	/* Setup IRQ domain */
-	domain = irq_domain_add_linear(node, 32,
+	domain = irq_domain_create_linear(domain_handle, LIOINTC_CHIP_IRQ,
 					&irq_generic_chip_ops, priv);
 	if (!domain) {
 		pr_err("loongson-liointc: cannot add IRQ domain\n");
-		err = -EINVAL;
-		goto out_iounmap_isr;
+		goto out_iounmap;
 	}
 
-	err = irq_alloc_domain_generic_chips(domain, 32, 1,
-					node->full_name, handle_level_irq,
-					IRQ_NOPROBE, 0, 0);
+	err = irq_alloc_domain_generic_chips(domain, LIOINTC_CHIP_IRQ, 1,
+					(node ? node->full_name : "LIOINTC"),
+					handle_level_irq, 0, IRQ_NOPROBE, 0);
 	if (err) {
 		pr_err("loongson-liointc: unable to register IRQ domain\n");
 		goto out_free_domain;
@@ -289,24 +259,111 @@ static int __init liointc_of_init(struct device_node *node,
 				liointc_chained_handle_irq, &priv->handler[i]);
 	}
 
+	liointc_domain = domain;
 	return 0;
 
 out_free_domain:
 	irq_domain_remove(domain);
-out_iounmap_isr:
-	for (i = 0; i < LIOINTC_NUM_CORES; i++) {
-		if (!priv->core_isr[i])
-			continue;
-		iounmap(priv->core_isr[i]);
-	}
-out_iounmap_base:
+out_iounmap:
 	iounmap(base);
 out_free_priv:
 	kfree(priv);
 
-	return err;
+	return -EINVAL;
+}
+
+#ifdef CONFIG_OF
+
+static int __init liointc_of_init(struct device_node *node,
+				  struct device_node *parent)
+{
+	bool have_parent = FALSE;
+	int sz, i, index, revision, err = 0;
+	struct resource res;
+
+	if (!of_device_is_compatible(node, "loongson,liointc-2.0")) {
+		index = 0;
+		revision = 1;
+	} else {
+		index = of_property_match_string(node, "reg-names", "main");
+		revision = 2;
+	}
+
+	if (of_address_to_resource(node, index, &res))
+		return -EINVAL;
+
+	for (i = 0; i < LIOINTC_NUM_PARENT; i++) {
+		parent_irq[i] = of_irq_get_byname(node, parent_names[i]);
+		if (parent_irq[i] > 0)
+			have_parent = TRUE;
+	}
+	if (!have_parent)
+		return -ENODEV;
+
+	sz = of_property_read_variable_u32_array(node,
+						"loongson,parent_int_map",
+						&parent_int_map[0],
+						LIOINTC_NUM_PARENT,
+						LIOINTC_NUM_PARENT);
+	if (sz < 4) {
+		pr_err("loongson-liointc: No parent_int_map\n");
+		return -ENODEV;
+	}
+
+	err = liointc_init(res.start, resource_size(&res),
+			revision, of_node_to_fwnode(node), node);
+	if (err < 0)
+		return err;
+
+	return 0;
 }
 
 IRQCHIP_DECLARE(loongson_liointc_1_0, "loongson,liointc-1.0", liointc_of_init);
 IRQCHIP_DECLARE(loongson_liointc_1_0a, "loongson,liointc-1.0a", liointc_of_init);
 IRQCHIP_DECLARE(loongson_liointc_2_0, "loongson,liointc-2.0", liointc_of_init);
+
+#endif
+
+#ifdef CONFIG_ACPI
+static int __init
+htintc_parse_madt(union acpi_subtable_headers *header,
+		       const unsigned long end)
+{
+	struct acpi_madt_ht_pic *htintc_entry = (struct acpi_madt_ht_pic *)header;
+
+	return htvec_acpi_init(liointc_domain, htintc_entry);
+}
+
+static int __init acpi_cascade_irqdomain_init(void)
+{
+	acpi_table_parse_madt(ACPI_MADT_TYPE_HT_PIC,
+			      htintc_parse_madt, 0);
+	return 0;
+}
+int __init liointc_acpi_init(struct irq_domain *parent, struct acpi_madt_lio_pic *acpi_liointc)
+{
+	int ret;
+	struct fwnode_handle *domain_handle;
+
+	if (!acpi_liointc)
+		return -EINVAL;
+
+	parent_int_map[0] = acpi_liointc->cascade_map[0];
+	parent_int_map[1] = acpi_liointc->cascade_map[1];
+
+	parent_irq[0] = irq_create_mapping(parent, acpi_liointc->cascade[0]);
+	parent_irq[1] = irq_create_mapping(parent, acpi_liointc->cascade[1]);
+
+	domain_handle = irq_domain_alloc_fwnode((phys_addr_t *)acpi_liointc);
+	if (!domain_handle) {
+		pr_err("Unable to allocate domain handle\n");
+		return -ENOMEM;
+	}
+	ret = liointc_init(acpi_liointc->address, acpi_liointc->size,
+			   1, domain_handle, NULL);
+	if (ret == 0)
+		acpi_cascade_irqdomain_init();
+
+	return ret;
+}
+#endif
-- 
1.8.3.1

[PATCH RFC 09/10] irqchip: Add Loongson Extended I/O interrupt controller support

[Jianmin Lv]

We are preparing to add new Loongson (based on LoongArch, not compatible
with old MIPS-based Loongson) support. This patch add Loongson Extended
I/O CPU interrupt controller support.

EIOINTC stands for "Extended I/O Interrupts" that described in Section
11.2 of "Loongson 3A5000 Processor Reference Manual". For more
information please refer Documentation/loongarch/irq-chip-model.rst.

Loongson-3A5000 has 4 cores per NUMA node, and each NUMA node has an
EIOINTC; while Loongson-3C5000 has 16 cores per NUMA node, and each NUMA
node has 4 EIOINTCs. In other words, 16 cores of one NUMA node in
Loongson-3C5000 are organized in 4 groups, each group connects to an
EIOINTC. We call the "group" here as an EIOINTC node, so each EIOINTC
node always includes 4 cores (both in Loongson-3A5000 and Loongson-
3C5000).

Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Jianmin Lv <lvjianmin@loongson.cn>
---
 drivers/irqchip/Kconfig                |  10 +
 drivers/irqchip/Makefile               |   1 +
 drivers/irqchip/irq-loongson-eiointc.c | 381 +++++++++++++++++++++++++++++++++
 include/linux/cpuhotplug.h             |   1 +
 4 files changed, 393 insertions(+)
 create mode 100644 drivers/irqchip/irq-loongson-eiointc.c

diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index a596ee7..eea0c15 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -564,6 +564,16 @@ config LOONGSON_LIOINTC
 	help
 	  Support for the Loongson Local I/O Interrupt Controller.
 
+config LOONGSON_EIOINTC
+	bool "Loongson Extend I/O Interrupt Controller"
+	depends on LOONGARCH
+	depends on MACH_LOONGSON64
+	default MACH_LOONGSON64
+	select IRQ_DOMAIN_HIERARCHY
+	select GENERIC_IRQ_CHIP
+	help
+	  Support for the Loongson3 Extend I/O Interrupt Vector Controller.
+
 config LOONGSON_HTPIC
 	bool "Loongson3 HyperTransport PIC Controller"
 	depends on (MACH_LOONGSON64 && MIPS)
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index 736f030..0d82759 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -107,6 +107,7 @@ obj-$(CONFIG_TI_SCI_INTA_IRQCHIP)	+= irq-ti-sci-inta.o
 obj-$(CONFIG_TI_PRUSS_INTC)		+= irq-pruss-intc.o
 obj-$(CONFIG_IRQ_LOONGARCH_CPU)		+= irq-loongarch-cpu.o irq-loongarch-pic-common.o
 obj-$(CONFIG_LOONGSON_LIOINTC)		+= irq-loongson-liointc.o
+obj-$(CONFIG_LOONGSON_EIOINTC)		+= irq-loongson-eiointc.o
 obj-$(CONFIG_LOONGSON_HTPIC)		+= irq-loongson-htpic.o
 obj-$(CONFIG_LOONGSON_HTVEC)		+= irq-loongson-htvec.o
 obj-$(CONFIG_LOONGSON_PCH_PIC)		+= irq-loongson-pch-pic.o
diff --git a/drivers/irqchip/irq-loongson-eiointc.c b/drivers/irqchip/irq-loongson-eiointc.c
new file mode 100644
index 0000000..e72caf5
--- /dev/null
+++ b/drivers/irqchip/irq-loongson-eiointc.c
@@ -0,0 +1,381 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Loongson Extend I/O Interrupt Controller support
+ *
+ * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
+ */
+
+#define pr_fmt(fmt) "eiointc: " fmt
+
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqchip.h>
+#include <linux/irqdomain.h>
+#include <linux/irqchip/chained_irq.h>
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
+#include <linux/syscore_ops.h>
+#include "irq-loongarch-pic-common.h"
+
+#define EIOINTC_REG_NODEMAP	0x14a0
+#define EIOINTC_REG_IPMAP	0x14c0
+#define EIOINTC_REG_ENABLE	0x1600
+#define EIOINTC_REG_BOUNCE	0x1680
+#define EIOINTC_REG_ISR		0x1800
+#define EIOINTC_REG_ROUTE	0x1c00
+
+#define VEC_REG_COUNT		4
+#define VEC_COUNT_PER_REG	64
+#define VEC_COUNT		(VEC_REG_COUNT * VEC_COUNT_PER_REG)
+#define VEC_REG_IDX(irq_id)	((irq_id) / VEC_COUNT_PER_REG)
+#define VEC_REG_BIT(irq_id)     ((irq_id) % VEC_COUNT_PER_REG)
+#define EIOINTC_ALL_ENABLE	0xffffffff
+
+#define MAX_EIO_NODES		(NR_CPUS / CORES_PER_EIO_NODE)
+
+static int nr_pics;
+
+struct eiointc_priv {
+	u32			node;
+	nodemask_t		node_map;
+	cpumask_t		cpuspan_map;
+	struct fwnode_handle	*domain_handle;
+	struct irq_domain	*eiointc_domain;
+};
+
+static struct eiointc_priv *eiointc_priv[2];
+
+int eiointc_get_node(int id)
+{
+	return eiointc_priv[id]->node;
+}
+
+static int cpu_to_eio_node(int cpu)
+{
+	return cpu_logical_map(cpu) / CORES_PER_EIO_NODE;
+}
+
+static void eiointc_set_irq_route(int pos, unsigned int cpu, unsigned int mnode, nodemask_t *node_map)
+{
+	int i, node, cpu_node, route_node;
+	unsigned char coremap[MAX_EIO_NODES];
+	uint32_t pos_off, data, data_byte, data_mask;
+
+	pos_off = pos & ~3;
+	data_byte = pos & 3;
+	data_mask = ~BIT_MASK(data_byte) & 0xf;
+
+	memset(coremap, 0, sizeof(unsigned char) * MAX_EIO_NODES);
+
+	/* Calculate node and coremap of target irq */
+	cpu_node = cpu_logical_map(cpu) / CORES_PER_EIO_NODE;
+	coremap[cpu_node] |= BIT(cpu_logical_map(cpu) % CORES_PER_EIO_NODE);
+
+	for_each_online_cpu(i) {
+		node = cpu_to_eio_node(i);
+		if (!node_isset(node, *node_map))
+			continue;
+
+		/* EIO node 0 is in charge of inter-node interrupt dispatch */
+		route_node = (node == mnode) ? cpu_node : node;
+		data = ((coremap[node] | (route_node << 4)) << (data_byte * 8));
+		csr_any_send(EIOINTC_REG_ROUTE + pos_off, data, data_mask, node * CORES_PER_EIO_NODE);
+	}
+}
+
+static DEFINE_RAW_SPINLOCK(affinity_lock);
+
+static int eiointc_set_irq_affinity(struct irq_data *d, const struct cpumask *affinity, bool force)
+{
+	unsigned int cpu;
+	unsigned long flags;
+	uint32_t vector, regaddr;
+	struct cpumask intersect_affinity;
+	struct eiointc_priv *priv = d->domain->host_data;
+
+	if (!IS_ENABLED(CONFIG_SMP))
+		return -EPERM;
+
+	raw_spin_lock_irqsave(&affinity_lock, flags);
+
+	cpumask_and(&intersect_affinity, affinity, cpu_online_mask);
+	cpumask_and(&intersect_affinity, &intersect_affinity, &priv->cpuspan_map);
+
+	if (cpumask_empty(&intersect_affinity)) {
+		raw_spin_unlock_irqrestore(&affinity_lock, flags);
+		return -EINVAL;
+	}
+	cpu = cpumask_first(&intersect_affinity);
+
+	if (!d->parent_data)
+		vector = d->hwirq;
+	else
+		vector = d->parent_data->hwirq;
+
+	regaddr = EIOINTC_REG_ENABLE + ((vector >> 5) << 2);
+
+	/* Mask target vector */
+	csr_any_send(regaddr, EIOINTC_ALL_ENABLE & (~BIT(vector & 0x1F)),
+			0x0, priv->node * CORES_PER_EIO_NODE);
+
+	/* Set route for target vector */
+	eiointc_set_irq_route(vector, cpu, priv->node, &priv->node_map);
+
+	/* Unmask target vector */
+	csr_any_send(regaddr, EIOINTC_ALL_ENABLE,
+			0x0, priv->node * CORES_PER_EIO_NODE);
+
+	irq_data_update_effective_affinity(d, cpumask_of(cpu));
+
+	raw_spin_unlock_irqrestore(&affinity_lock, flags);
+
+	return IRQ_SET_MASK_OK;
+}
+
+static int eiointc_index(int node)
+{
+	int i;
+
+	for (i = 0; i < nr_pics; i++) {
+		if (node_isset(node, eiointc_priv[i]->node_map))
+			return i;
+	}
+
+	return -1;
+}
+
+static int eiointc_router_init(unsigned int cpu)
+{
+	int i, bit;
+	int node = cpu_to_eio_node(cpu);
+	int index = eiointc_index(node);
+	uint32_t data;
+
+	if (index < 0) {
+		pr_err("Error: invalid nodemap!\n");
+		return -1;
+	}
+
+	if ((cpu_logical_map(cpu) % CORES_PER_EIO_NODE) == 0) {
+		eiointc_enable();
+
+		for (i = 0; i < VEC_COUNT / 32; i++) {
+			data = (((1 << (i * 2 + 1)) << 16) | (1 << (i * 2)));
+			iocsr_writel(data, EIOINTC_REG_NODEMAP + i * 4);
+		}
+
+		for (i = 0; i < VEC_COUNT / 32 / 4; i++) {
+			bit = BIT(1 + index); /* Route to IP[1 + index] */
+			data = bit | (bit << 8) | (bit << 16) | (bit << 24);
+			iocsr_writel(data, EIOINTC_REG_IPMAP + i * 4);
+		}
+
+		for (i = 0; i < VEC_COUNT / 4; i++) {
+			/* Route to Node-0 Core-0 */
+			if (index == 0)
+				bit = BIT(cpu_logical_map(0));
+			else
+				bit = (eiointc_priv[index]->node << 4) | 1;
+
+			data = bit | (bit << 8) | (bit << 16) | (bit << 24);
+			iocsr_writel(data, EIOINTC_REG_ROUTE + i * 4);
+		}
+
+		for (i = 0; i < VEC_COUNT / 32; i++) {
+			data = 0xffffffff;
+			iocsr_writel(data, EIOINTC_REG_ENABLE + i * 4);
+			iocsr_writel(data, EIOINTC_REG_BOUNCE + i * 4);
+		}
+	}
+
+	return 0;
+}
+
+static void eiointc_irq_dispatch(struct irq_desc *desc)
+{
+	int i;
+	u64 pending;
+	bool handled = false;
+	struct irq_chip *chip = irq_desc_get_chip(desc);
+	struct eiointc_priv *priv = irq_desc_get_handler_data(desc);
+
+	chained_irq_enter(chip, desc);
+
+	for (i = 0; i < VEC_REG_COUNT; i++) {
+		pending = iocsr_readq(EIOINTC_REG_ISR + (i << 3));
+		iocsr_writeq(pending, EIOINTC_REG_ISR + (i << 3));
+		while (pending) {
+			int bit = __ffs(pending);
+			int irq = bit + VEC_COUNT_PER_REG * i;
+
+			generic_handle_domain_irq(priv->eiointc_domain, irq);
+			pending &= ~BIT(bit);
+			handled = true;
+		}
+	}
+
+	if (!handled)
+		spurious_interrupt();
+
+	chained_irq_exit(chip, desc);
+}
+
+static void eiointc_ack_irq(struct irq_data *d)
+{
+	if (d->parent_data)
+		irq_chip_ack_parent(d);
+}
+
+static void eiointc_mask_irq(struct irq_data *d)
+{
+	if (d->parent_data)
+		irq_chip_mask_parent(d);
+}
+
+static void eiointc_unmask_irq(struct irq_data *d)
+{
+	if (d->parent_data)
+		irq_chip_unmask_parent(d);
+}
+
+static struct irq_chip eiointc_irq_chip = {
+	.name			= "EIOINTC",
+	.irq_ack		= eiointc_ack_irq,
+	.irq_mask		= eiointc_mask_irq,
+	.irq_unmask		= eiointc_unmask_irq,
+	.irq_set_affinity	= eiointc_set_irq_affinity,
+};
+
+static int eiointc_domain_alloc(struct irq_domain *domain, unsigned int virq,
+				unsigned int nr_irqs, void *arg)
+{
+	int ret;
+	unsigned int i, type;
+	unsigned long hwirq = 0;
+	struct eiointc *priv = domain->host_data;
+
+	ret = irq_domain_translate_onecell(domain, arg, &hwirq, &type);
+	if (ret < 0)
+		return -EINVAL;
+
+	if (hwirq >= IOCSR_EXTIOI_VECTOR_NUM)
+		return -EINVAL;
+
+	for (i = 0; i < nr_irqs; i++) {
+		irq_domain_set_info(domain, virq + i, hwirq + i, &eiointc_irq_chip,
+					priv, handle_edge_irq, NULL, NULL);
+	}
+
+	return 0;
+}
+
+static void eiointc_domain_free(struct irq_domain *domain, unsigned int virq,
+				unsigned int nr_irqs)
+{
+	int i;
+
+	for (i = 0; i < nr_irqs; i++) {
+		struct irq_data *d = irq_domain_get_irq_data(domain, virq + i);
+
+		irq_set_handler(virq + i, NULL);
+		irq_domain_reset_irq_data(d);
+	}
+}
+
+static const struct irq_domain_ops eiointc_domain_ops = {
+	.translate	= irq_domain_translate_onecell,
+	.alloc		= eiointc_domain_alloc,
+	.free		= eiointc_domain_free,
+};
+
+static int eiointc_suspend(void)
+{
+	return 0;
+}
+
+static void eiointc_resume(void)
+{
+	int i, j;
+	struct irq_desc *desc;
+	struct irq_data *irq_data;
+
+	eiointc_router_init(0);
+
+	for (i = 0; i < nr_pics; i++) {
+		for (j = 0; j < VEC_COUNT; j++) {
+			desc = irq_resolve_mapping(eiointc_priv[i]->eiointc_domain, j);
+			if (desc && desc->handle_irq && desc->handle_irq != handle_bad_irq) {
+				irq_data = &desc->irq_data;
+				eiointc_set_irq_affinity(irq_data, irq_data->common->affinity, 0);
+			}
+		}
+	}
+}
+
+static struct syscore_ops eiointc_syscore_ops = {
+	.suspend = eiointc_suspend,
+	.resume = eiointc_resume,
+};
+
+int __init eiointc_acpi_init(struct irq_domain *parent,
+				     struct acpi_madt_eio_pic *acpi_eiointc)
+{
+	int i, parent_irq;
+	unsigned long node_map;
+	struct eiointc_priv *priv;
+
+	if (!acpi_eiointc)
+		return -EINVAL;
+
+	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->domain_handle = irq_domain_alloc_fwnode((phys_addr_t *)acpi_eiointc);
+	if (!priv->domain_handle) {
+		pr_err("Unable to allocate domain handle\n");
+		goto out_free_priv;
+	}
+
+	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_priv;
+	}
+
+	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);
+
+	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_vector_parent(acpi_eiointc->node, priv->eiointc_domain);
+	return 0;
+
+out_free_priv:
+	priv->domain_handle = NULL;
+	kfree(priv);
+
+	return -ENOMEM;
+}
diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h
index 82e3313..2af7c658 100644
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h
@@ -150,6 +150,7 @@ enum cpuhp_state {
 	CPUHP_AP_IRQ_BCM2836_STARTING,
 	CPUHP_AP_IRQ_MIPS_GIC_STARTING,
 	CPUHP_AP_IRQ_RISCV_STARTING,
+	CPUHP_AP_IRQ_LOONGARCH_STARTING,
 	CPUHP_AP_IRQ_SIFIVE_PLIC_STARTING,
 	CPUHP_AP_ARM_MVEBU_COHERENCY,
 	CPUHP_AP_MICROCODE_LOADER,
-- 
1.8.3.1

[PATCH RFC 10/10] irqchip: Add Loongson PCH LPC controller support

[Jianmin Lv]

We are preparing to add new Loongson (based on LoongArch, not compatible
with old MIPS-based Loongson) support. This patch add Loongson PCH LPC
interrupt controller support.

PCH-LPC stands for "LPC Interrupts" that described in Section 24.3 of
"Loongson 7A1000 Bridge User Manual". For more information please refer
Documentation/loongarch/irq-chip-model.rst.

Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Jianmin Lv <lvjianmin@loongson.cn>
---
 drivers/irqchip/Kconfig                |   8 ++
 drivers/irqchip/Makefile               |   1 +
 drivers/irqchip/irq-loongson-pch-lpc.c | 225 +++++++++++++++++++++++++++++++++
 3 files changed, 234 insertions(+)
 create mode 100644 drivers/irqchip/irq-loongson-pch-lpc.c

diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index eea0c15..c56a8db 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -610,6 +610,14 @@ config LOONGSON_PCH_MSI
 	help
 	  Support for the Loongson PCH MSI Controller.
 
+config LOONGSON_PCH_LPC
+	bool "Loongson PCH LPC Controller"
+	depends on MACH_LOONGSON64
+	default (MACH_LOONGSON64 && LOONGARCH)
+	select IRQ_DOMAIN_HIERARCHY
+	help
+	  Support for the Loongson PCH LPC Controller.
+
 config MST_IRQ
 	bool "MStar Interrupt Controller"
 	depends on ARCH_MEDIATEK || ARCH_MSTARV7 || COMPILE_TEST
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index 0d82759..a57566c 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -112,6 +112,7 @@ obj-$(CONFIG_LOONGSON_HTPIC)		+= irq-loongson-htpic.o
 obj-$(CONFIG_LOONGSON_HTVEC)		+= irq-loongson-htvec.o
 obj-$(CONFIG_LOONGSON_PCH_PIC)		+= irq-loongson-pch-pic.o
 obj-$(CONFIG_LOONGSON_PCH_MSI)		+= irq-loongson-pch-msi.o
+obj-$(CONFIG_LOONGSON_PCH_LPC)		+= irq-loongson-pch-lpc.o
 obj-$(CONFIG_MST_IRQ)			+= irq-mst-intc.o
 obj-$(CONFIG_SL28CPLD_INTC)		+= irq-sl28cpld.o
 obj-$(CONFIG_MACH_REALTEK_RTL)		+= irq-realtek-rtl.o
diff --git a/drivers/irqchip/irq-loongson-pch-lpc.c b/drivers/irqchip/irq-loongson-pch-lpc.c
new file mode 100644
index 0000000..18e400d
--- /dev/null
+++ b/drivers/irqchip/irq-loongson-pch-lpc.c
@@ -0,0 +1,225 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Loongson LPC Interrupt Controller support
+ *
+ * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
+ */
+
+#define pr_fmt(fmt) "lpc: " fmt
+
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqchip.h>
+#include <linux/irqchip/chained_irq.h>
+#include <linux/irqdomain.h>
+#include <linux/kernel.h>
+#include <linux/syscore_ops.h>
+
+/* Registers */
+#define LPC_INT_CTL		0x00
+#define LPC_INT_ENA		0x04
+#define LPC_INT_STS		0x08
+#define LPC_INT_CLR		0x0c
+#define LPC_INT_POL		0x10
+#define LPC_COUNT		16
+
+struct pch_lpc {
+	void __iomem		*base;
+	struct irq_domain	*lpc_domain;
+	struct fwnode_handle	*domain_handle;
+	raw_spinlock_t		lpc_lock;
+	u32			saved_reg_ctl;
+	u32			saved_reg_ena;
+	u32			saved_reg_pol;
+};
+
+static struct pch_lpc *pch_lpc_priv;
+
+static void ack_lpc_irq(struct irq_data *d)
+{
+	unsigned long flags;
+
+	raw_spin_lock_irqsave(&pch_lpc_priv->lpc_lock, flags);
+	writel(0x1 << d->irq, pch_lpc_priv->base + LPC_INT_CLR);
+	raw_spin_unlock_irqrestore(&pch_lpc_priv->lpc_lock, flags);
+}
+static void mask_lpc_irq(struct irq_data *d)
+{
+	unsigned long flags;
+
+	raw_spin_lock_irqsave(&pch_lpc_priv->lpc_lock, flags);
+	writel(readl(pch_lpc_priv->base + LPC_INT_ENA) & (~(0x1 << (d->irq))),
+			pch_lpc_priv->base + LPC_INT_ENA);
+	raw_spin_unlock_irqrestore(&pch_lpc_priv->lpc_lock, flags);
+}
+
+static void mask_ack_lpc_irq(struct irq_data *d)
+{
+}
+
+static void unmask_lpc_irq(struct irq_data *d)
+{
+	unsigned long flags;
+
+	raw_spin_lock_irqsave(&pch_lpc_priv->lpc_lock, flags);
+	writel(readl(pch_lpc_priv->base + LPC_INT_ENA) | (0x1 << (d->irq)),
+			pch_lpc_priv->base + LPC_INT_ENA);
+	raw_spin_unlock_irqrestore(&pch_lpc_priv->lpc_lock, flags);
+}
+
+static int lpc_set_type(struct irq_data *d, unsigned int type)
+{
+	u32 val;
+	u32 mask = 0x1 << (d->hwirq);
+
+	if (!(type & IRQ_TYPE_LEVEL_MASK))
+		return 0;
+
+	val = readl(pch_lpc_priv->base + LPC_INT_POL);
+
+	if (type == IRQ_TYPE_LEVEL_HIGH)
+		val |= mask;
+	else
+		val &= ~mask;
+
+	writel(val, pch_lpc_priv->base + LPC_INT_POL);
+
+	return 0;
+}
+
+static struct irq_chip pch_lpc_irq_chip = {
+	.name			= "PCH LPC",
+	.irq_mask		= mask_lpc_irq,
+	.irq_unmask		= unmask_lpc_irq,
+	.irq_ack		= ack_lpc_irq,
+	.irq_mask_ack		= mask_ack_lpc_irq,
+	.irq_eoi		= unmask_lpc_irq,
+	.irq_set_type		= lpc_set_type,
+	.flags			= IRQCHIP_SKIP_SET_WAKE,
+};
+
+static void lpc_irq_dispatch(struct irq_desc *desc)
+{
+	struct irq_chip *chip = irq_desc_get_chip(desc);
+	u32 pending;
+
+	chained_irq_enter(chip, desc);
+
+	pending = readl(pch_lpc_priv->base + LPC_INT_ENA);
+	pending &= readl(pch_lpc_priv->base + LPC_INT_STS);
+	if (!pending)
+		spurious_interrupt();
+
+	while (pending) {
+		int bit = __ffs(pending);
+
+		generic_handle_irq(bit);
+		pending &= ~BIT(bit);
+	}
+	chained_irq_exit(chip, desc);
+}
+
+static int pch_lpc_map(struct irq_domain *d, unsigned int irq,
+			irq_hw_number_t hw)
+{
+	irq_set_chip_and_handler(irq, &pch_lpc_irq_chip, handle_level_irq);
+	return 0;
+}
+
+static const struct irq_domain_ops pch_lpc_domain_ops = {
+	.map 		= pch_lpc_map,
+	.translate	= irq_domain_translate_twocell,
+};
+
+static void pch_lpc_reset(struct pch_lpc *priv)
+{
+	/* Enable the LPC interrupt, bit31: en  bit30: edge */
+	writel(0x80000000, priv->base + LPC_INT_CTL);
+	writel(0, priv->base + LPC_INT_ENA);
+	/* Clear all 18-bit interrpt bit */
+	writel(0x3ffff, priv->base + LPC_INT_CLR);
+}
+
+static int pch_lpc_disabled(struct pch_lpc *priv)
+{
+	return (readl(priv->base + LPC_INT_ENA) == 0xffffffff) &&
+			(readl(priv->base + LPC_INT_STS) == 0xffffffff);
+}
+
+static int pch_lpc_suspend(void)
+{
+	pch_lpc_priv->saved_reg_ctl = readl(pch_lpc_priv->base + LPC_INT_CTL);
+	pch_lpc_priv->saved_reg_ena = readl(pch_lpc_priv->base + LPC_INT_ENA);
+	pch_lpc_priv->saved_reg_pol = readl(pch_lpc_priv->base + LPC_INT_POL);
+	return 0;
+}
+
+static void pch_lpc_resume(void)
+{
+	writel(pch_lpc_priv->saved_reg_ctl, pch_lpc_priv->base + LPC_INT_CTL);
+	writel(pch_lpc_priv->saved_reg_ena, pch_lpc_priv->base + LPC_INT_ENA);
+	writel(pch_lpc_priv->saved_reg_pol, pch_lpc_priv->base + LPC_INT_POL);
+}
+
+static struct syscore_ops pch_lpc_syscore_ops = {
+	.suspend = pch_lpc_suspend,
+	.resume = pch_lpc_resume,
+};
+
+int __init pch_lpc_acpi_init(struct irq_domain *parent,
+					struct acpi_madt_lpc_pic *acpi_pchlpc)
+{
+	int parent_irq;
+	struct pch_lpc *priv;
+	struct irq_fwspec fwspec;
+
+	if (!acpi_pchlpc)
+		return -EINVAL;
+
+	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	raw_spin_lock_init(&priv->lpc_lock);
+
+	priv->base = ioremap(acpi_pchlpc->address, acpi_pchlpc->size);
+	if (!priv->base)
+		goto free_priv;
+
+	if (pch_lpc_disabled(priv)) {
+		pr_err("Failed to get LPC status\n");
+		goto iounmap_base;
+	}
+
+	priv->domain_handle = irq_domain_alloc_fwnode((phys_addr_t *)acpi_pchlpc);
+	if (!priv->domain_handle) {
+		pr_err("Unable to allocate domain handle\n");
+		goto iounmap_base;
+	}
+	priv->lpc_domain = irq_domain_add_legacy(NULL, LPC_COUNT, 0, 0,
+						&pch_lpc_domain_ops, priv);
+	if (!priv->lpc_domain) {
+		pr_err("Failed to create IRQ domain\n");
+		goto iounmap_base;
+	}
+	pch_lpc_reset(priv);
+
+	fwspec.fwnode = parent->fwnode;
+	fwspec.param[0] = acpi_pchlpc->cascade;
+	fwspec.param[1] = IRQ_TYPE_LEVEL_HIGH;
+	fwspec.param_count = 2;
+	parent_irq = irq_create_fwspec_mapping(&fwspec);
+	irq_set_chained_handler_and_data(parent_irq, lpc_irq_dispatch, priv);
+	pch_lpc_priv = priv;
+
+	register_syscore_ops(&pch_lpc_syscore_ops);
+	pch_lpc_domain = priv->lpc_domain;
+	return 0;
+
+iounmap_base:
+	iounmap(priv->base);
+free_priv:
+	kfree(priv);
+
+	return -ENOMEM;
+}
-- 
1.8.3.1