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path: root/drivers/irqchip/irq-sun4i.c
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Diffstat (limited to 'drivers/irqchip/irq-sun4i.c')
-rw-r--r--drivers/irqchip/irq-sun4i.c202
1 files changed, 202 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-sun4i.c b/drivers/irqchip/irq-sun4i.c
new file mode 100644
index 0000000000..dd506ebfda
--- /dev/null
+++ b/drivers/irqchip/irq-sun4i.c
@@ -0,0 +1,202 @@
+/*
+ * Allwinner A1X SoCs IRQ chip driver.
+ *
+ * Copyright (C) 2012 Maxime Ripard
+ *
+ * Maxime Ripard <maxime.ripard@free-electrons.com>
+ *
+ * Based on code from
+ * Allwinner Technology Co., Ltd. <www.allwinnertech.com>
+ * Benn Huang <benn@allwinnertech.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/irqchip.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+#include <asm/exception.h>
+
+#define SUN4I_IRQ_VECTOR_REG 0x00
+#define SUN4I_IRQ_PROTECTION_REG 0x08
+#define SUN4I_IRQ_NMI_CTRL_REG 0x0c
+#define SUN4I_IRQ_PENDING_REG(x) (0x10 + 0x4 * x)
+#define SUN4I_IRQ_FIQ_PENDING_REG(x) (0x20 + 0x4 * x)
+#define SUN4I_IRQ_ENABLE_REG(data, x) ((data)->enable_reg_offset + 0x4 * x)
+#define SUN4I_IRQ_MASK_REG(data, x) ((data)->mask_reg_offset + 0x4 * x)
+#define SUN4I_IRQ_ENABLE_REG_OFFSET 0x40
+#define SUN4I_IRQ_MASK_REG_OFFSET 0x50
+#define SUNIV_IRQ_ENABLE_REG_OFFSET 0x20
+#define SUNIV_IRQ_MASK_REG_OFFSET 0x30
+
+struct sun4i_irq_chip_data {
+ void __iomem *irq_base;
+ struct irq_domain *irq_domain;
+ u32 enable_reg_offset;
+ u32 mask_reg_offset;
+};
+
+static struct sun4i_irq_chip_data *irq_ic_data;
+
+static void __exception_irq_entry sun4i_handle_irq(struct pt_regs *regs);
+
+static void sun4i_irq_ack(struct irq_data *irqd)
+{
+ unsigned int irq = irqd_to_hwirq(irqd);
+
+ if (irq != 0)
+ return; /* Only IRQ 0 / the ENMI needs to be acked */
+
+ writel(BIT(0), irq_ic_data->irq_base + SUN4I_IRQ_PENDING_REG(0));
+}
+
+static void sun4i_irq_mask(struct irq_data *irqd)
+{
+ unsigned int irq = irqd_to_hwirq(irqd);
+ unsigned int irq_off = irq % 32;
+ int reg = irq / 32;
+ u32 val;
+
+ val = readl(irq_ic_data->irq_base +
+ SUN4I_IRQ_ENABLE_REG(irq_ic_data, reg));
+ writel(val & ~(1 << irq_off),
+ irq_ic_data->irq_base + SUN4I_IRQ_ENABLE_REG(irq_ic_data, reg));
+}
+
+static void sun4i_irq_unmask(struct irq_data *irqd)
+{
+ unsigned int irq = irqd_to_hwirq(irqd);
+ unsigned int irq_off = irq % 32;
+ int reg = irq / 32;
+ u32 val;
+
+ val = readl(irq_ic_data->irq_base +
+ SUN4I_IRQ_ENABLE_REG(irq_ic_data, reg));
+ writel(val | (1 << irq_off),
+ irq_ic_data->irq_base + SUN4I_IRQ_ENABLE_REG(irq_ic_data, reg));
+}
+
+static struct irq_chip sun4i_irq_chip = {
+ .name = "sun4i_irq",
+ .irq_eoi = sun4i_irq_ack,
+ .irq_mask = sun4i_irq_mask,
+ .irq_unmask = sun4i_irq_unmask,
+ .flags = IRQCHIP_EOI_THREADED | IRQCHIP_EOI_IF_HANDLED,
+};
+
+static int sun4i_irq_map(struct irq_domain *d, unsigned int virq,
+ irq_hw_number_t hw)
+{
+ irq_set_chip_and_handler(virq, &sun4i_irq_chip, handle_fasteoi_irq);
+ irq_set_probe(virq);
+
+ return 0;
+}
+
+static const struct irq_domain_ops sun4i_irq_ops = {
+ .map = sun4i_irq_map,
+ .xlate = irq_domain_xlate_onecell,
+};
+
+static int __init sun4i_of_init(struct device_node *node,
+ struct device_node *parent)
+{
+ irq_ic_data->irq_base = of_iomap(node, 0);
+ if (!irq_ic_data->irq_base)
+ panic("%pOF: unable to map IC registers\n",
+ node);
+
+ /* Disable all interrupts */
+ writel(0, irq_ic_data->irq_base + SUN4I_IRQ_ENABLE_REG(irq_ic_data, 0));
+ writel(0, irq_ic_data->irq_base + SUN4I_IRQ_ENABLE_REG(irq_ic_data, 1));
+ writel(0, irq_ic_data->irq_base + SUN4I_IRQ_ENABLE_REG(irq_ic_data, 2));
+
+ /* Unmask all the interrupts, ENABLE_REG(x) is used for masking */
+ writel(0, irq_ic_data->irq_base + SUN4I_IRQ_MASK_REG(irq_ic_data, 0));
+ writel(0, irq_ic_data->irq_base + SUN4I_IRQ_MASK_REG(irq_ic_data, 1));
+ writel(0, irq_ic_data->irq_base + SUN4I_IRQ_MASK_REG(irq_ic_data, 2));
+
+ /* Clear all the pending interrupts */
+ writel(0xffffffff, irq_ic_data->irq_base + SUN4I_IRQ_PENDING_REG(0));
+ writel(0xffffffff, irq_ic_data->irq_base + SUN4I_IRQ_PENDING_REG(1));
+ writel(0xffffffff, irq_ic_data->irq_base + SUN4I_IRQ_PENDING_REG(2));
+
+ /* Enable protection mode */
+ writel(0x01, irq_ic_data->irq_base + SUN4I_IRQ_PROTECTION_REG);
+
+ /* Configure the external interrupt source type */
+ writel(0x00, irq_ic_data->irq_base + SUN4I_IRQ_NMI_CTRL_REG);
+
+ irq_ic_data->irq_domain = irq_domain_add_linear(node, 3 * 32,
+ &sun4i_irq_ops, NULL);
+ if (!irq_ic_data->irq_domain)
+ panic("%pOF: unable to create IRQ domain\n", node);
+
+ set_handle_irq(sun4i_handle_irq);
+
+ return 0;
+}
+
+static int __init sun4i_ic_of_init(struct device_node *node,
+ struct device_node *parent)
+{
+ irq_ic_data = kzalloc(sizeof(struct sun4i_irq_chip_data), GFP_KERNEL);
+ if (!irq_ic_data)
+ return -ENOMEM;
+
+ irq_ic_data->enable_reg_offset = SUN4I_IRQ_ENABLE_REG_OFFSET;
+ irq_ic_data->mask_reg_offset = SUN4I_IRQ_MASK_REG_OFFSET;
+
+ return sun4i_of_init(node, parent);
+}
+
+IRQCHIP_DECLARE(allwinner_sun4i_ic, "allwinner,sun4i-a10-ic", sun4i_ic_of_init);
+
+static int __init suniv_ic_of_init(struct device_node *node,
+ struct device_node *parent)
+{
+ irq_ic_data = kzalloc(sizeof(struct sun4i_irq_chip_data), GFP_KERNEL);
+ if (!irq_ic_data)
+ return -ENOMEM;
+
+ irq_ic_data->enable_reg_offset = SUNIV_IRQ_ENABLE_REG_OFFSET;
+ irq_ic_data->mask_reg_offset = SUNIV_IRQ_MASK_REG_OFFSET;
+
+ return sun4i_of_init(node, parent);
+}
+
+IRQCHIP_DECLARE(allwinner_sunvi_ic, "allwinner,suniv-f1c100s-ic",
+ suniv_ic_of_init);
+
+static void __exception_irq_entry sun4i_handle_irq(struct pt_regs *regs)
+{
+ u32 hwirq;
+
+ /*
+ * hwirq == 0 can mean one of 3 things:
+ * 1) no more irqs pending
+ * 2) irq 0 pending
+ * 3) spurious irq
+ * So if we immediately get a reading of 0, check the irq-pending reg
+ * to differentiate between 2 and 3. We only do this once to avoid
+ * the extra check in the common case of 1 happening after having
+ * read the vector-reg once.
+ */
+ hwirq = readl(irq_ic_data->irq_base + SUN4I_IRQ_VECTOR_REG) >> 2;
+ if (hwirq == 0 &&
+ !(readl(irq_ic_data->irq_base + SUN4I_IRQ_PENDING_REG(0)) &
+ BIT(0)))
+ return;
+
+ do {
+ generic_handle_domain_irq(irq_ic_data->irq_domain, hwirq);
+ hwirq = readl(irq_ic_data->irq_base +
+ SUN4I_IRQ_VECTOR_REG) >> 2;
+ } while (hwirq != 0);
+}