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path: root/drivers/irqchip/irq-moxart.c
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Diffstat (limited to 'drivers/irqchip/irq-moxart.c')
-rw-r--r--drivers/irqchip/irq-moxart.c117
1 files changed, 117 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-moxart.c b/drivers/irqchip/irq-moxart.c
new file mode 100644
index 000000000000..5552fc2bf28a
--- /dev/null
+++ b/drivers/irqchip/irq-moxart.c
@@ -0,0 +1,117 @@
+/*
+ * MOXA ART SoCs IRQ chip driver.
+ *
+ * Copyright (C) 2013 Jonas Jensen
+ *
+ * Jonas Jensen <jonas.jensen@gmail.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/irqdomain.h>
+
+#include <asm/exception.h>
+
+#include "irqchip.h"
+
+#define IRQ_SOURCE_REG 0
+#define IRQ_MASK_REG 0x04
+#define IRQ_CLEAR_REG 0x08
+#define IRQ_MODE_REG 0x0c
+#define IRQ_LEVEL_REG 0x10
+#define IRQ_STATUS_REG 0x14
+
+#define FIQ_SOURCE_REG 0x20
+#define FIQ_MASK_REG 0x24
+#define FIQ_CLEAR_REG 0x28
+#define FIQ_MODE_REG 0x2c
+#define FIQ_LEVEL_REG 0x30
+#define FIQ_STATUS_REG 0x34
+
+
+struct moxart_irq_data {
+ void __iomem *base;
+ struct irq_domain *domain;
+ unsigned int interrupt_mask;
+};
+
+static struct moxart_irq_data intc;
+
+static asmlinkage void __exception_irq_entry handle_irq(struct pt_regs *regs)
+{
+ u32 irqstat;
+ int hwirq;
+
+ irqstat = readl(intc.base + IRQ_STATUS_REG);
+
+ while (irqstat) {
+ hwirq = ffs(irqstat) - 1;
+ handle_IRQ(irq_linear_revmap(intc.domain, hwirq), regs);
+ irqstat &= ~(1 << hwirq);
+ }
+}
+
+static int __init moxart_of_intc_init(struct device_node *node,
+ struct device_node *parent)
+{
+ unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN;
+ int ret;
+ struct irq_chip_generic *gc;
+
+ intc.base = of_iomap(node, 0);
+ if (!intc.base) {
+ pr_err("%s: unable to map IC registers\n",
+ node->full_name);
+ return -EINVAL;
+ }
+
+ intc.domain = irq_domain_add_linear(node, 32, &irq_generic_chip_ops,
+ intc.base);
+ if (!intc.domain) {
+ pr_err("%s: unable to create IRQ domain\n", node->full_name);
+ return -EINVAL;
+ }
+
+ ret = irq_alloc_domain_generic_chips(intc.domain, 32, 1,
+ "MOXARTINTC", handle_edge_irq,
+ clr, 0, IRQ_GC_INIT_MASK_CACHE);
+ if (ret) {
+ pr_err("%s: could not allocate generic chip\n",
+ node->full_name);
+ irq_domain_remove(intc.domain);
+ return -EINVAL;
+ }
+
+ ret = of_property_read_u32(node, "interrupt-mask",
+ &intc.interrupt_mask);
+ if (ret)
+ pr_err("%s: could not read interrupt-mask DT property\n",
+ node->full_name);
+
+ gc = irq_get_domain_generic_chip(intc.domain, 0);
+
+ gc->reg_base = intc.base;
+ gc->chip_types[0].regs.mask = IRQ_MASK_REG;
+ gc->chip_types[0].regs.ack = IRQ_CLEAR_REG;
+ gc->chip_types[0].chip.irq_ack = irq_gc_ack_set_bit;
+ gc->chip_types[0].chip.irq_mask = irq_gc_mask_clr_bit;
+ gc->chip_types[0].chip.irq_unmask = irq_gc_mask_set_bit;
+
+ writel(0, intc.base + IRQ_MASK_REG);
+ writel(0xffffffff, intc.base + IRQ_CLEAR_REG);
+
+ writel(intc.interrupt_mask, intc.base + IRQ_MODE_REG);
+ writel(intc.interrupt_mask, intc.base + IRQ_LEVEL_REG);
+
+ set_handle_irq(handle_irq);
+
+ return 0;
+}
+IRQCHIP_DECLARE(moxa_moxart_ic, "moxa,moxart-ic", moxart_of_intc_init);