drivers/irqchip/irq-keystone.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Texas Instruments Keystone IRQ controller IP driver
   4  *
   5  * Copyright (C) 2014 Texas Instruments, Inc.
   6  * Author: Sajesh Kumar Saran <sajesh@ti.com>
   7  *         Grygorii Strashko <grygorii.strashko@ti.com>
   8  */
   9
  10 #include <linux/irq.h>
  11 #include <linux/bitops.h>
  12 #include <linux/module.h>
  13 #include <linux/moduleparam.h>
  14 #include <linux/interrupt.h>
  15 #include <linux/irqdomain.h>
  16 #include <linux/irqchip.h>
  17 #include <linux/of.h>
  18 #include <linux/platform_device.h>
  19 #include <linux/mfd/syscon.h>
  20 #include <linux/regmap.h>
  21
  22 /* The source ID bits start from 4 to 31 (total 28 bits)*/
  23 #define BIT_OFS                 4
  24 #define KEYSTONE_N_IRQ          (32 - BIT_OFS)
  25
  26 struct keystone_irq_device {
  27         struct device           *dev;
  28         struct irq_chip          chip;
  29         u32                      mask;
  30         int                      irq;
  31         struct irq_domain       *irqd;
  32         struct regmap           *devctrl_regs;
  33         u32                     devctrl_offset;
  34         raw_spinlock_t          wa_lock;
  35 };
  36
  37 static inline u32 keystone_irq_readl(struct keystone_irq_device *kirq)
  38 {
  39         int ret;
  40         u32 val = 0;
  41
  42         ret = regmap_read(kirq->devctrl_regs, kirq->devctrl_offset, &val);
  43         if (ret < 0)
  44                 dev_dbg(kirq->dev, "irq read failed ret(%d)\n", ret);
  45         return val;
  46 }
  47
  48 static inline void
  49 keystone_irq_writel(struct keystone_irq_device *kirq, u32 value)
  50 {
  51         int ret;
  52
  53         ret = regmap_write(kirq->devctrl_regs, kirq->devctrl_offset, value);
  54         if (ret < 0)
  55                 dev_dbg(kirq->dev, "irq write failed ret(%d)\n", ret);
  56 }
  57
  58 static void keystone_irq_setmask(struct irq_data *d)
  59 {
  60         struct keystone_irq_device *kirq = irq_data_get_irq_chip_data(d);
  61
  62         kirq->mask |= BIT(d->hwirq);
  63         dev_dbg(kirq->dev, "mask %lu [%x]\n", d->hwirq, kirq->mask);
  64 }
  65
  66 static void keystone_irq_unmask(struct irq_data *d)
  67 {
  68         struct keystone_irq_device *kirq = irq_data_get_irq_chip_data(d);
  69
  70         kirq->mask &= ~BIT(d->hwirq);
  71         dev_dbg(kirq->dev, "unmask %lu [%x]\n", d->hwirq, kirq->mask);
  72 }
  73
  74 static void keystone_irq_ack(struct irq_data *d)
  75 {
  76         /* nothing to do here */
  77 }
  78
  79 static irqreturn_t keystone_irq_handler(int irq, void *keystone_irq)
  80 {
  81         struct keystone_irq_device *kirq = keystone_irq;
  82         unsigned long wa_lock_flags;
  83         unsigned long pending;
  84         int src, err;
  85
  86         dev_dbg(kirq->dev, "start irq %d\n", irq);
  87
  88         pending = keystone_irq_readl(kirq);
  89         keystone_irq_writel(kirq, pending);
  90
  91         dev_dbg(kirq->dev, "pending 0x%lx, mask 0x%x\n", pending, kirq->mask);
  92
  93         pending = (pending >> BIT_OFS) & ~kirq->mask;
  94
  95         dev_dbg(kirq->dev, "pending after mask 0x%lx\n", pending);
  96
  97         for (src = 0; src < KEYSTONE_N_IRQ; src++) {
  98                 if (BIT(src) & pending) {
  99                         raw_spin_lock_irqsave(&kirq->wa_lock, wa_lock_flags);
 100                         err = generic_handle_domain_irq(kirq->irqd, src);
 101                         raw_spin_unlock_irqrestore(&kirq->wa_lock,
 102                                                    wa_lock_flags);
 103
 104                         if (err)
 105                                 dev_warn_ratelimited(kirq->dev, "spurious irq detected hwirq %d\n",
 106                                                      src);
 107                 }
 108         }
 109
 110         dev_dbg(kirq->dev, "end irq %d\n", irq);
 111         return IRQ_HANDLED;
 112 }
 113
 114 static int keystone_irq_map(struct irq_domain *h, unsigned int virq,
 115                                 irq_hw_number_t hw)
 116 {
 117         struct keystone_irq_device *kirq = h->host_data;
 118
 119         irq_set_chip_data(virq, kirq);
 120         irq_set_chip_and_handler(virq, &kirq->chip, handle_level_irq);
 121         irq_set_probe(virq);
 122         return 0;
 123 }
 124
 125 static const struct irq_domain_ops keystone_irq_ops = {
 126         .map    = keystone_irq_map,
 127         .xlate  = irq_domain_xlate_onecell,
 128 };
 129
 130 static int keystone_irq_probe(struct platform_device *pdev)
 131 {
 132         struct device *dev = &pdev->dev;
 133         struct device_node *np = dev->of_node;
 134         struct keystone_irq_device *kirq;
 135         int ret;
 136
 137         if (np == NULL)
 138                 return -EINVAL;
 139
 140         kirq = devm_kzalloc(dev, sizeof(*kirq), GFP_KERNEL);
 141         if (!kirq)
 142                 return -ENOMEM;
 143
 144         kirq->devctrl_regs =
 145                 syscon_regmap_lookup_by_phandle(np, "ti,syscon-dev");
 146         if (IS_ERR(kirq->devctrl_regs))
 147                 return PTR_ERR(kirq->devctrl_regs);
 148
 149         ret = of_property_read_u32_index(np, "ti,syscon-dev", 1,
 150                                          &kirq->devctrl_offset);
 151         if (ret) {
 152                 dev_err(dev, "couldn't read the devctrl_offset offset!\n");
 153                 return ret;
 154         }
 155
 156         kirq->irq = platform_get_irq(pdev, 0);
 157         if (kirq->irq < 0)
 158                 return kirq->irq;
 159
 160         kirq->dev = dev;
 161         kirq->mask = ~0x0;
 162         kirq->chip.name         = "keystone-irq";
 163         kirq->chip.irq_ack      = keystone_irq_ack;
 164         kirq->chip.irq_mask     = keystone_irq_setmask;
 165         kirq->chip.irq_unmask   = keystone_irq_unmask;
 166
 167         kirq->irqd = irq_domain_add_linear(np, KEYSTONE_N_IRQ,
 168                                            &keystone_irq_ops, kirq);
 169         if (!kirq->irqd) {
 170                 dev_err(dev, "IRQ domain registration failed\n");
 171                 return -ENODEV;
 172         }
 173
 174         raw_spin_lock_init(&kirq->wa_lock);
 175
 176         platform_set_drvdata(pdev, kirq);
 177
 178         ret = request_irq(kirq->irq, keystone_irq_handler,
 179                           0, dev_name(dev), kirq);
 180         if (ret) {
 181                 irq_domain_remove(kirq->irqd);
 182                 return ret;
 183         }
 184
 185         /* clear all source bits */
 186         keystone_irq_writel(kirq, ~0x0);
 187
 188         dev_info(dev, "irqchip registered, nr_irqs %u\n", KEYSTONE_N_IRQ);
 189
 190         return 0;
 191 }
 192
 193 static void keystone_irq_remove(struct platform_device *pdev)
 194 {
 195         struct keystone_irq_device *kirq = platform_get_drvdata(pdev);
 196         int hwirq;
 197
 198         free_irq(kirq->irq, kirq);
 199
 200         for (hwirq = 0; hwirq < KEYSTONE_N_IRQ; hwirq++)
 201                 irq_dispose_mapping(irq_find_mapping(kirq->irqd, hwirq));
 202
 203         irq_domain_remove(kirq->irqd);
 204 }
 205
 206 static const struct of_device_id keystone_irq_dt_ids[] = {
 207         { .compatible = "ti,keystone-irq", },
 208         {},
 209 };
 210 MODULE_DEVICE_TABLE(of, keystone_irq_dt_ids);
 211
 212 static struct platform_driver keystone_irq_device_driver = {
 213         .probe          = keystone_irq_probe,
 214         .remove         = keystone_irq_remove,
 215         .driver         = {
 216                 .name   = "keystone_irq",
 217                 .of_match_table = of_match_ptr(keystone_irq_dt_ids),
 218         }
 219 };
 220
 221 module_platform_driver(keystone_irq_device_driver);
 222
 223 MODULE_AUTHOR("Texas Instruments");
 224 MODULE_AUTHOR("Sajesh Kumar Saran");
 225 MODULE_AUTHOR("Grygorii Strashko");
 226 MODULE_DESCRIPTION("Keystone IRQ chip");
 227 MODULE_LICENSE("GPL v2");