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Diffstat (limited to 'arch/arm/mach-exynos/irq-combiner.c')
-rw-r--r--arch/arm/mach-exynos/irq-combiner.c124
1 files changed, 124 insertions, 0 deletions
diff --git a/arch/arm/mach-exynos/irq-combiner.c b/arch/arm/mach-exynos/irq-combiner.c
new file mode 100644
index 00000000000..5a2758ab055
--- /dev/null
+++ b/arch/arm/mach-exynos/irq-combiner.c
@@ -0,0 +1,124 @@
+/* linux/arch/arm/mach-exynos4/irq-combiner.c
+ *
+ * Copyright (c) 2010-2011 Samsung Electronics Co., Ltd.
+ * http://www.samsung.com
+ *
+ * Based on arch/arm/common/gic.c
+ *
+ * IRQ COMBINER support
+ *
+ * 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/io.h>
+
+#include <asm/mach/irq.h>
+
+#define COMBINER_ENABLE_SET 0x0
+#define COMBINER_ENABLE_CLEAR 0x4
+#define COMBINER_INT_STATUS 0xC
+
+static DEFINE_SPINLOCK(irq_controller_lock);
+
+struct combiner_chip_data {
+ unsigned int irq_offset;
+ unsigned int irq_mask;
+ void __iomem *base;
+};
+
+static struct combiner_chip_data combiner_data[MAX_COMBINER_NR];
+
+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->irq % 32);
+
+ __raw_writel(mask, combiner_base(data) + COMBINER_ENABLE_CLEAR);
+}
+
+static void combiner_unmask_irq(struct irq_data *data)
+{
+ u32 mask = 1 << (data->irq % 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 = __ffs(status);
+
+ cascade_irq = combiner_irq + (chip_data->irq_offset & ~31);
+ if (unlikely(cascade_irq >= NR_IRQS))
+ do_bad_IRQ(cascade_irq, desc);
+ else
+ generic_handle_irq(cascade_irq);
+
+ out:
+ chained_irq_exit(chip, desc);
+}
+
+static struct irq_chip combiner_chip = {
+ .name = "COMBINER",
+ .irq_mask = combiner_mask_irq,
+ .irq_unmask = combiner_unmask_irq,
+};
+
+void __init combiner_cascade_irq(unsigned int combiner_nr, unsigned int irq)
+{
+ if (combiner_nr >= MAX_COMBINER_NR)
+ BUG();
+ if (irq_set_handler_data(irq, &combiner_data[combiner_nr]) != 0)
+ BUG();
+ irq_set_chained_handler(irq, combiner_handle_cascade_irq);
+}
+
+void __init combiner_init(unsigned int combiner_nr, void __iomem *base,
+ unsigned int irq_start)
+{
+ unsigned int i;
+
+ if (combiner_nr >= MAX_COMBINER_NR)
+ BUG();
+
+ combiner_data[combiner_nr].base = base;
+ combiner_data[combiner_nr].irq_offset = irq_start;
+ combiner_data[combiner_nr].irq_mask = 0xff << ((combiner_nr % 4) << 3);
+
+ /* Disable all interrupts */
+
+ __raw_writel(combiner_data[combiner_nr].irq_mask,
+ base + COMBINER_ENABLE_CLEAR);
+
+ /* Setup the Linux IRQ subsystem */
+
+ for (i = irq_start; i < combiner_data[combiner_nr].irq_offset
+ + MAX_IRQ_IN_COMBINER; i++) {
+ irq_set_chip_and_handler(i, &combiner_chip, handle_level_irq);
+ irq_set_chip_data(i, &combiner_data[combiner_nr]);
+ set_irq_flags(i, IRQF_VALID | IRQF_PROBE);
+ }
+}