Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / irqchip / exynos-combiner.c
diff --git a/kernel/drivers/irqchip/exynos-combiner.c b/kernel/drivers/irqchip/exynos-combiner.c
new file mode 100644 (file)
index 0000000..5945223
--- /dev/null
@@ -0,0 +1,227 @@
+/*
+ * 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/irqdomain.h>
+#include <linux/irqchip/chained_irq.h>
+#include <linux/interrupt.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+#include "irqchip.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;
+};
+
+static struct irq_domain *combiner_irq_domain;
+
+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);
+
+       __raw_writel(mask, combiner_base(data) + COMBINER_ENABLE_CLEAR);
+}
+
+static void combiner_unmask_irq(struct irq_data *data)
+{
+       u32 mask = 1 << (data->hwirq % 32);
+
+       __raw_writel(mask, combiner_base(data) + COMBINER_ENABLE_SET);
+}
+
+static void combiner_handle_cascade_irq(unsigned int irq, struct irq_desc *desc)
+{
+       struct combiner_chip_data *chip_data = irq_get_handler_data(irq);
+       struct irq_chip *chip = irq_get_chip(irq);
+       unsigned int cascade_irq, combiner_irq;
+       unsigned long status;
+
+       chained_irq_enter(chip, desc);
+
+       spin_lock(&irq_controller_lock);
+       status = __raw_readl(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(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)
+{
+       if (irq_set_handler_data(irq, combiner_data) != 0)
+               BUG();
+       irq_set_chained_handler(irq, combiner_handle_cascade_irq);
+}
+
+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 */
+       __raw_writel(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 (d->of_node != 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]);
+       set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
+
+       return 0;
+}
+
+static 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,
+                                unsigned int max_nr)
+{
+       int i, irq;
+       unsigned int nr_irq;
+       struct combiner_chip_data *combiner_data;
+
+       nr_irq = max_nr * IRQ_IN_COMBINER;
+
+       combiner_data = kcalloc(max_nr, sizeof (*combiner_data), GFP_KERNEL);
+       if (!combiner_data) {
+               pr_warning("%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_warning("%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);
+       }
+}
+
+static int __init combiner_of_init(struct device_node *np,
+                                  struct device_node *parent)
+{
+       void __iomem *combiner_base;
+       unsigned int max_nr = 20;
+
+       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, max_nr);
+
+       return 0;
+}
+IRQCHIP_DECLARE(exynos4210_combiner, "samsung,exynos4210-combiner",
+               combiner_of_init);