1 files changed, 279 insertions, 0 deletions
diff --git a/drivers/irqchip/exynos-combiner.c b/drivers/irqchip/exynos-combiner.c
new file mode 100644
index 000000000..b78a169c9
--- /dev/null
+++ b/drivers/irqchip/exynos-combiner.c
@@ -0,0 +1,279 @@
+/*
+ * Copyright (c) 2010-2011 Samsung Electronics Co., Ltd.
+ *		http://www.samsung.com
+ *
+ * Combiner irqchip for EXYNOS
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/err.h>
+#include <linux/export.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/syscore_ops.h>
+#include <linux/irqdomain.h>
+#include <linux/irqchip.h>
+#include <linux/irqchip/chained_irq.h>
+#include <linux/interrupt.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+#define COMBINER_ENABLE_SET	0x0
+#define COMBINER_ENABLE_CLEAR	0x4
+#define COMBINER_INT_STATUS	0xC
+
+#define IRQ_IN_COMBINER		8
+
+static DEFINE_SPINLOCK(irq_controller_lock);
+
+struct combiner_chip_data {
+	unsigned int hwirq_offset;
+	unsigned int irq_mask;
+	void __iomem *base;
+	unsigned int parent_irq;
+#ifdef CONFIG_PM
+	u32 pm_save;
+#endif
+};
+
+static struct combiner_chip_data *combiner_data;
+static struct irq_domain *combiner_irq_domain;
+static unsigned int max_nr = 20;
+
+static inline void __iomem *combiner_base(struct irq_data *data)
+{
+	struct combiner_chip_data *combiner_data =
+		irq_data_get_irq_chip_data(data);
+
+	return combiner_data->base;
+}
+
+static void combiner_mask_irq(struct irq_data *data)
+{
+	u32 mask = 1 << (data->hwirq % 32);
+
+	writel_relaxed(mask, combiner_base(data) + COMBINER_ENABLE_CLEAR);
+}
+
+static void combiner_unmask_irq(struct irq_data *data)
+{
+	u32 mask = 1 << (data->hwirq % 32);
+
+	writel_relaxed(mask, combiner_base(data) + COMBINER_ENABLE_SET);
+}
+
+static void combiner_handle_cascade_irq(struct irq_desc *desc)
+{
+	struct combiner_chip_data *chip_data = irq_desc_get_handler_data(desc);
+	struct irq_chip *chip = irq_desc_get_chip(desc);
+	unsigned int cascade_irq, combiner_irq;
+	unsigned long status;
+
+	chained_irq_enter(chip, desc);
+
+	spin_lock(&irq_controller_lock);
+	status = readl_relaxed(chip_data->base + COMBINER_INT_STATUS);
+	spin_unlock(&irq_controller_lock);
+	status &= chip_data->irq_mask;
+
+	if (status == 0)
+		goto out;
+
+	combiner_irq = chip_data->hwirq_offset + __ffs(status);
+	cascade_irq = irq_find_mapping(combiner_irq_domain, combiner_irq);
+
+	if (unlikely(!cascade_irq))
+		handle_bad_irq(desc);
+	else
+		generic_handle_irq(cascade_irq);
+
+ out:
+	chained_irq_exit(chip, desc);
+}
+
+#ifdef CONFIG_SMP
+static int combiner_set_affinity(struct irq_data *d,
+				 const struct cpumask *mask_val, bool force)
+{
+	struct combiner_chip_data *chip_data = irq_data_get_irq_chip_data(d);
+	struct irq_chip *chip = irq_get_chip(chip_data->parent_irq);
+	struct irq_data *data = irq_get_irq_data(chip_data->parent_irq);
+
+	if (chip && chip->irq_set_affinity)
+		return chip->irq_set_affinity(data, mask_val, force);
+	else
+		return -EINVAL;
+}
+#endif
+
+static struct irq_chip combiner_chip = {
+	.name			= "COMBINER",
+	.irq_mask		= combiner_mask_irq,
+	.irq_unmask		= combiner_unmask_irq,
+#ifdef CONFIG_SMP
+	.irq_set_affinity	= combiner_set_affinity,
+#endif
+};
+
+static void __init combiner_cascade_irq(struct combiner_chip_data *combiner_data,
+					unsigned int irq)
+{
+	irq_set_chained_handler_and_data(irq, combiner_handle_cascade_irq,
+					 combiner_data);
+}
+
+static void __init combiner_init_one(struct combiner_chip_data *combiner_data,
+				     unsigned int combiner_nr,
+				     void __iomem *base, unsigned int irq)
+{
+	combiner_data->base = base;
+	combiner_data->hwirq_offset = (combiner_nr & ~3) * IRQ_IN_COMBINER;
+	combiner_data->irq_mask = 0xff << ((combiner_nr % 4) << 3);
+	combiner_data->parent_irq = irq;
+
+	/* Disable all interrupts */
+	writel_relaxed(combiner_data->irq_mask, base + COMBINER_ENABLE_CLEAR);
+}
+
+static int combiner_irq_domain_xlate(struct irq_domain *d,
+				     struct device_node *controller,
+				     const u32 *intspec, unsigned int intsize,
+				     unsigned long *out_hwirq,
+				     unsigned int *out_type)
+{
+	if (irq_domain_get_of_node(d) != controller)
+		return -EINVAL;
+
+	if (intsize < 2)
+		return -EINVAL;
+
+	*out_hwirq = intspec[0] * IRQ_IN_COMBINER + intspec[1];
+	*out_type = 0;
+
+	return 0;
+}
+
+static int combiner_irq_domain_map(struct irq_domain *d, unsigned int irq,
+				   irq_hw_number_t hw)
+{
+	struct combiner_chip_data *combiner_data = d->host_data;
+
+	irq_set_chip_and_handler(irq, &combiner_chip, handle_level_irq);
+	irq_set_chip_data(irq, &combiner_data[hw >> 3]);
+	irq_set_probe(irq);
+
+	return 0;
+}
+
+static const struct irq_domain_ops combiner_irq_domain_ops = {
+	.xlate	= combiner_irq_domain_xlate,
+	.map	= combiner_irq_domain_map,
+};
+
+static void __init combiner_init(void __iomem *combiner_base,
+				 struct device_node *np)
+{
+	int i, irq;
+	unsigned int nr_irq;
+
+	nr_irq = max_nr * IRQ_IN_COMBINER;
+
+	combiner_data = kcalloc(max_nr, sizeof (*combiner_data), GFP_KERNEL);
+	if (!combiner_data) {
+		pr_warn("%s: could not allocate combiner data\n", __func__);
+		return;
+	}
+
+	combiner_irq_domain = irq_domain_add_linear(np, nr_irq,
+				&combiner_irq_domain_ops, combiner_data);
+	if (WARN_ON(!combiner_irq_domain)) {
+		pr_warn("%s: irq domain init failed\n", __func__);
+		return;
+	}
+
+	for (i = 0; i < max_nr; i++) {
+		irq = irq_of_parse_and_map(np, i);
+
+		combiner_init_one(&combiner_data[i], i,
+				  combiner_base + (i >> 2) * 0x10, irq);
+		combiner_cascade_irq(&combiner_data[i], irq);
+	}
+}
+
+#ifdef CONFIG_PM
+
+/**
+ * combiner_suspend - save interrupt combiner state before suspend
+ *
+ * Save the interrupt enable set register for all combiner groups since
+ * the state is lost when the system enters into a sleep state.
+ *
+ */
+static int combiner_suspend(void)
+{
+	int i;
+
+	for (i = 0; i < max_nr; i++)
+		combiner_data[i].pm_save =
+			readl_relaxed(combiner_data[i].base + COMBINER_ENABLE_SET);
+
+	return 0;
+}
+
+/**
+ * combiner_resume - restore interrupt combiner state after resume
+ *
+ * Restore the interrupt enable set register for all combiner groups since
+ * the state is lost when the system enters into a sleep state on suspend.
+ *
+ */
+static void combiner_resume(void)
+{
+	int i;
+
+	for (i = 0; i < max_nr; i++) {
+		writel_relaxed(combiner_data[i].irq_mask,
+			     combiner_data[i].base + COMBINER_ENABLE_CLEAR);
+		writel_relaxed(combiner_data[i].pm_save,
+			     combiner_data[i].base + COMBINER_ENABLE_SET);
+	}
+}
+
+#else
+#define combiner_suspend	NULL
+#define combiner_resume		NULL
+#endif
+
+static struct syscore_ops combiner_syscore_ops = {
+	.suspend	= combiner_suspend,
+	.resume		= combiner_resume,
+};
+
+static int __init combiner_of_init(struct device_node *np,
+				   struct device_node *parent)
+{
+	void __iomem *combiner_base;
+
+	combiner_base = of_iomap(np, 0);
+	if (!combiner_base) {
+		pr_err("%s: failed to map combiner registers\n", __func__);
+		return -ENXIO;
+	}
+
+	if (of_property_read_u32(np, "samsung,combiner-nr", &max_nr)) {
+		pr_info("%s: number of combiners not specified, "
+			"setting default as %d.\n",
+			__func__, max_nr);
+	}
+
+	combiner_init(combiner_base, np);
+
+	register_syscore_ops(&combiner_syscore_ops);
+
+	return 0;
+}
+IRQCHIP_DECLARE(exynos4210_combiner, "samsung,exynos4210-combiner",
+		combiner_of_init);