1 files changed, 232 insertions, 0 deletions

diff --git a/drivers/irqchip/irq-keystone.c b/drivers/irqchip/irq-keystone.c
new file mode 100644
index 000000000000..608abf9c9283
--- /dev/null
+++ b/drivers/irqchip/irq-keystone.c
@@ -0,0 +1,232 @@
+/*
+ * Texas Instruments Keystone IRQ controller IP driver
+ *
+ * Copyright (C) 2014 Texas Instruments, Inc.
+ * Author: Sajesh Kumar Saran <sajesh@ti.com>
+ *         Grygorii Strashko <grygorii.strashko@ti.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation version 2.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/irq.h>
+#include <linux/bitops.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/irqdomain.h>
+#include <linux/irqchip/chained_irq.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/mfd/syscon.h>
+#include <linux/regmap.h>
+#include "irqchip.h"
+
+
+/* The source ID bits start from 4 to 31 (total 28 bits)*/
+#define BIT_OFS                 4
+#define KEYSTONE_N_IRQ          (32 - BIT_OFS)
+
+struct keystone_irq_device {
+        struct device           *dev;
+        struct irq_chip          chip;
+        u32                      mask;
+        int                      irq;
+        struct irq_domain       *irqd;
+        struct regmap           *devctrl_regs;
+        u32                     devctrl_offset;
+};
+
+static inline u32 keystone_irq_readl(struct keystone_irq_device *kirq)
+{
+        int ret;
+        u32 val = 0;
+
+        ret = regmap_read(kirq->devctrl_regs, kirq->devctrl_offset, &val);
+        if (ret < 0)
+                dev_dbg(kirq->dev, "irq read failed ret(%d)\n", ret);
+        return val;
+}
+
+static inline void
+keystone_irq_writel(struct keystone_irq_device *kirq, u32 value)
+{
+        int ret;
+
+        ret = regmap_write(kirq->devctrl_regs, kirq->devctrl_offset, value);
+        if (ret < 0)
+                dev_dbg(kirq->dev, "irq write failed ret(%d)\n", ret);
+}
+
+static void keystone_irq_setmask(struct irq_data *d)
+{
+        struct keystone_irq_device *kirq = irq_data_get_irq_chip_data(d);
+
+        kirq->mask |= BIT(d->hwirq);
+        dev_dbg(kirq->dev, "mask %lu [%x]\n", d->hwirq, kirq->mask);
+}
+
+static void keystone_irq_unmask(struct irq_data *d)
+{
+        struct keystone_irq_device *kirq = irq_data_get_irq_chip_data(d);
+
+        kirq->mask &= ~BIT(d->hwirq);
+        dev_dbg(kirq->dev, "unmask %lu [%x]\n", d->hwirq, kirq->mask);
+}
+
+static void keystone_irq_ack(struct irq_data *d)
+{
+        /* nothing to do here */
+}
+
+static void keystone_irq_handler(unsigned irq, struct irq_desc *desc)
+{
+        struct keystone_irq_device *kirq = irq_desc_get_handler_data(desc);
+        unsigned long pending;
+        int src, virq;
+
+        dev_dbg(kirq->dev, "start irq %d\n", irq);
+
+        chained_irq_enter(irq_desc_get_chip(desc), desc);
+
+        pending = keystone_irq_readl(kirq);
+        keystone_irq_writel(kirq, pending);
+
+        dev_dbg(kirq->dev, "pending 0x%lx, mask 0x%x\n", pending, kirq->mask);
+
+        pending = (pending >> BIT_OFS) & ~kirq->mask;
+
+        dev_dbg(kirq->dev, "pending after mask 0x%lx\n", pending);
+
+        for (src = 0; src < KEYSTONE_N_IRQ; src++) {
+                if (BIT(src) & pending) {
+                        virq = irq_find_mapping(kirq->irqd, src);
+                        dev_dbg(kirq->dev, "dispatch bit %d, virq %d\n",
+                                src, virq);
+                        if (!virq)
+                                dev_warn(kirq->dev, "sporious irq detected hwirq %d, virq %d\n",
+                                         src, virq);
+                        generic_handle_irq(virq);
+                }
+        }
+
+        chained_irq_exit(irq_desc_get_chip(desc), desc);
+
+        dev_dbg(kirq->dev, "end irq %d\n", irq);
+}
+
+static int keystone_irq_map(struct irq_domain *h, unsigned int virq,
+                                irq_hw_number_t hw)
+{
+        struct keystone_irq_device *kirq = h->host_data;
+
+        irq_set_chip_data(virq, kirq);
+        irq_set_chip_and_handler(virq, &kirq->chip, handle_level_irq);
+        set_irq_flags(virq, IRQF_VALID | IRQF_PROBE);
+        return 0;
+}
+
+static struct irq_domain_ops keystone_irq_ops = {
+        .map    = keystone_irq_map,
+        .xlate  = irq_domain_xlate_onecell,
+};
+
+static int keystone_irq_probe(struct platform_device *pdev)
+{
+        struct device *dev = &pdev->dev;
+        struct device_node *np = dev->of_node;
+        struct keystone_irq_device *kirq;
+        int ret;
+
+        if (np == NULL)
+                return -EINVAL;
+
+        kirq = devm_kzalloc(dev, sizeof(*kirq), GFP_KERNEL);
+        if (!kirq)
+                return -ENOMEM;
+
+        kirq->devctrl_regs =
+                syscon_regmap_lookup_by_phandle(np, "ti,syscon-dev");
+        if (IS_ERR(kirq->devctrl_regs))
+                return PTR_ERR(kirq->devctrl_regs);
+
+        ret = of_property_read_u32_index(np, "ti,syscon-dev", 1,
+                                         &kirq->devctrl_offset);
+        if (ret) {
+                dev_err(dev, "couldn't read the devctrl_offset offset!\n");
+                return ret;
+        }
+
+        kirq->irq = platform_get_irq(pdev, 0);
+        if (kirq->irq < 0) {
+                dev_err(dev, "no irq resource %d\n", kirq->irq);
+                return kirq->irq;
+        }
+
+        kirq->dev = dev;
+        kirq->mask = ~0x0;
+        kirq->chip.name         = "keystone-irq";
+        kirq->chip.irq_ack      = keystone_irq_ack;
+        kirq->chip.irq_mask     = keystone_irq_setmask;
+        kirq->chip.irq_unmask   = keystone_irq_unmask;
+
+        kirq->irqd = irq_domain_add_linear(np, KEYSTONE_N_IRQ,
+                                           &keystone_irq_ops, kirq);
+        if (!kirq->irqd) {
+                dev_err(dev, "IRQ domain registration failed\n");
+                return -ENODEV;
+        }
+
+        platform_set_drvdata(pdev, kirq);
+
+        irq_set_chained_handler(kirq->irq, keystone_irq_handler);
+        irq_set_handler_data(kirq->irq, kirq);
+
+        /* clear all source bits */
+        keystone_irq_writel(kirq, ~0x0);
+
+        dev_info(dev, "irqchip registered, nr_irqs %u\n", KEYSTONE_N_IRQ);
+
+        return 0;
+}
+
+static int keystone_irq_remove(struct platform_device *pdev)
+{
+        struct keystone_irq_device *kirq = platform_get_drvdata(pdev);
+        int hwirq;
+
+        for (hwirq = 0; hwirq < KEYSTONE_N_IRQ; hwirq++)
+                irq_dispose_mapping(irq_find_mapping(kirq->irqd, hwirq));
+
+        irq_domain_remove(kirq->irqd);
+        return 0;
+}
+
+static const struct of_device_id keystone_irq_dt_ids[] = {
+        { .compatible = "ti,keystone-irq", },
+        {},
+};
+MODULE_DEVICE_TABLE(of, keystone_irq_dt_ids);
+
+static struct platform_driver keystone_irq_device_driver = {
+        .probe          = keystone_irq_probe,
+        .remove         = keystone_irq_remove,
+        .driver         = {
+                .name   = "keystone_irq",
+                .owner  = THIS_MODULE,
+                .of_match_table = of_match_ptr(keystone_irq_dt_ids),
+        }
+};
+
+module_platform_driver(keystone_irq_device_driver);
+
+MODULE_AUTHOR("Texas Instruments");
+MODULE_AUTHOR("Sajesh Kumar Saran");
+MODULE_AUTHOR("Grygorii Strashko");
+MODULE_DESCRIPTION("Keystone IRQ chip");
+MODULE_LICENSE("GPL v2");