diff options
Diffstat (limited to 'drivers/irqchip/irq-keystone.c')
| -rw-r--r-- | drivers/irqchip/irq-keystone.c | 238 |
1 files changed, 238 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-keystone.c b/drivers/irqchip/irq-keystone.c new file mode 100644 index 000000000..8118ebe80 --- /dev/null +++ b/drivers/irqchip/irq-keystone.c @@ -0,0 +1,238 @@ +/* + * 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/interrupt.h> +#include <linux/irqdomain.h> +#include <linux/irqchip.h> +#include <linux/of.h> +#include <linux/of_platform.h> +#include <linux/mfd/syscon.h> +#include <linux/regmap.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; + raw_spinlock_t wa_lock; +}; + +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 irqreturn_t keystone_irq_handler(int irq, void *keystone_irq) +{ + struct keystone_irq_device *kirq = keystone_irq; + unsigned long wa_lock_flags; + unsigned long pending; + int src, virq; + + dev_dbg(kirq->dev, "start irq %d\n", irq); + + 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, "spurious irq detected hwirq %d, virq %d\n", + src, virq); + raw_spin_lock_irqsave(&kirq->wa_lock, wa_lock_flags); + generic_handle_irq(virq); + raw_spin_unlock_irqrestore(&kirq->wa_lock, + wa_lock_flags); + } + } + + dev_dbg(kirq->dev, "end irq %d\n", irq); + return IRQ_HANDLED; +} + +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); + irq_set_probe(virq); + return 0; +} + +static const 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) + 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; + } + + raw_spin_lock_init(&kirq->wa_lock); + + platform_set_drvdata(pdev, kirq); + + ret = request_irq(kirq->irq, keystone_irq_handler, + 0, dev_name(dev), kirq); + if (ret) { + irq_domain_remove(kirq->irqd); + return ret; + } + + /* 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; + + free_irq(kirq->irq, kirq); + + 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", + .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"); |