drivers/irqchip/irq-mvebu-pic.c

   1 /*
   2  * Copyright (C) 2016 Marvell
   3  *
   4  * Yehuda Yitschak <yehuday@marvell.com>
   5  * Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
   6  *
   7  * This file is licensed under the terms of the GNU General Public
   8  * License version 2.  This program is licensed "as is" without any
   9  * warranty of any kind, whether express or implied.
  10  */
  11
  12 #include <linux/interrupt.h>
  13 #include <linux/io.h>
  14 #include <linux/irq.h>
  15 #include <linux/irqchip.h>
  16 #include <linux/irqchip/chained_irq.h>
  17 #include <linux/irqdomain.h>
  18 #include <linux/module.h>
  19 #include <linux/of_irq.h>
  20 #include <linux/platform_device.h>
  21 #include <linux/seq_file.h>
  22
  23 #define PIC_CAUSE              0x0
  24 #define PIC_MASK               0x4
  25
  26 #define PIC_MAX_IRQS            32
  27 #define PIC_MAX_IRQ_MASK        ((1UL << PIC_MAX_IRQS) - 1)
  28
  29 struct mvebu_pic {
  30         void __iomem *base;
  31         u32 parent_irq;
  32         struct irq_domain *domain;
  33         struct platform_device *pdev;
  34 };
  35
  36 static void mvebu_pic_reset(struct mvebu_pic *pic)
  37 {
  38         /* ACK and mask all interrupts */
  39         writel(0, pic->base + PIC_MASK);
  40         writel(PIC_MAX_IRQ_MASK, pic->base + PIC_CAUSE);
  41 }
  42
  43 static void mvebu_pic_eoi_irq(struct irq_data *d)
  44 {
  45         struct mvebu_pic *pic = irq_data_get_irq_chip_data(d);
  46
  47         writel(1 << d->hwirq, pic->base + PIC_CAUSE);
  48 }
  49
  50 static void mvebu_pic_mask_irq(struct irq_data *d)
  51 {
  52         struct mvebu_pic *pic = irq_data_get_irq_chip_data(d);
  53         u32 reg;
  54
  55         reg =  readl(pic->base + PIC_MASK);
  56         reg |= (1 << d->hwirq);
  57         writel(reg, pic->base + PIC_MASK);
  58 }
  59
  60 static void mvebu_pic_unmask_irq(struct irq_data *d)
  61 {
  62         struct mvebu_pic *pic = irq_data_get_irq_chip_data(d);
  63         u32 reg;
  64
  65         reg = readl(pic->base + PIC_MASK);
  66         reg &= ~(1 << d->hwirq);
  67         writel(reg, pic->base + PIC_MASK);
  68 }
  69
  70 static void mvebu_pic_print_chip(struct irq_data *d, struct seq_file *p)
  71 {
  72         struct mvebu_pic *pic = irq_data_get_irq_chip_data(d);
  73
  74         seq_printf(p, dev_name(&pic->pdev->dev));
  75 }
  76
  77 static const struct irq_chip mvebu_pic_chip = {
  78         .irq_mask       = mvebu_pic_mask_irq,
  79         .irq_unmask     = mvebu_pic_unmask_irq,
  80         .irq_eoi        = mvebu_pic_eoi_irq,
  81         .irq_print_chip = mvebu_pic_print_chip,
  82 };
  83
  84 static int mvebu_pic_irq_map(struct irq_domain *domain, unsigned int virq,
  85                              irq_hw_number_t hwirq)
  86 {
  87         struct mvebu_pic *pic = domain->host_data;
  88
  89         irq_set_percpu_devid(virq);
  90         irq_set_chip_data(virq, pic);
  91         irq_set_chip_and_handler(virq, &mvebu_pic_chip, handle_percpu_devid_irq);
  92         irq_set_status_flags(virq, IRQ_LEVEL);
  93         irq_set_probe(virq);
  94
  95         return 0;
  96 }
  97
  98 static const struct irq_domain_ops mvebu_pic_domain_ops = {
  99         .map = mvebu_pic_irq_map,
 100         .xlate = irq_domain_xlate_onecell,
 101 };
 102
 103 static void mvebu_pic_handle_cascade_irq(struct irq_desc *desc)
 104 {
 105         struct mvebu_pic *pic = irq_desc_get_handler_data(desc);
 106         struct irq_chip *chip = irq_desc_get_chip(desc);
 107         unsigned long irqmap, irqn;
 108
 109         irqmap = readl_relaxed(pic->base + PIC_CAUSE);
 110         chained_irq_enter(chip, desc);
 111
 112         for_each_set_bit(irqn, &irqmap, BITS_PER_LONG)
 113                 generic_handle_domain_irq(pic->domain, irqn);
 114
 115         chained_irq_exit(chip, desc);
 116 }
 117
 118 static void mvebu_pic_enable_percpu_irq(void *data)
 119 {
 120         struct mvebu_pic *pic = data;
 121
 122         mvebu_pic_reset(pic);
 123         enable_percpu_irq(pic->parent_irq, IRQ_TYPE_NONE);
 124 }
 125
 126 static void mvebu_pic_disable_percpu_irq(void *data)
 127 {
 128         struct mvebu_pic *pic = data;
 129
 130         disable_percpu_irq(pic->parent_irq);
 131 }
 132
 133 static int mvebu_pic_probe(struct platform_device *pdev)
 134 {
 135         struct device_node *node = pdev->dev.of_node;
 136         struct mvebu_pic *pic;
 137
 138         pic = devm_kzalloc(&pdev->dev, sizeof(struct mvebu_pic), GFP_KERNEL);
 139         if (!pic)
 140                 return -ENOMEM;
 141
 142         pic->pdev = pdev;
 143         pic->base = devm_platform_ioremap_resource(pdev, 0);
 144         if (IS_ERR(pic->base))
 145                 return PTR_ERR(pic->base);
 146
 147         pic->parent_irq = irq_of_parse_and_map(node, 0);
 148         if (pic->parent_irq <= 0) {
 149                 dev_err(&pdev->dev, "Failed to parse parent interrupt\n");
 150                 return -EINVAL;
 151         }
 152
 153         pic->domain = irq_domain_add_linear(node, PIC_MAX_IRQS,
 154                                             &mvebu_pic_domain_ops, pic);
 155         if (!pic->domain) {
 156                 dev_err(&pdev->dev, "Failed to allocate irq domain\n");
 157                 return -ENOMEM;
 158         }
 159
 160         irq_set_chained_handler(pic->parent_irq, mvebu_pic_handle_cascade_irq);
 161         irq_set_handler_data(pic->parent_irq, pic);
 162
 163         on_each_cpu(mvebu_pic_enable_percpu_irq, pic, 1);
 164
 165         platform_set_drvdata(pdev, pic);
 166
 167         return 0;
 168 }
 169
 170 static int mvebu_pic_remove(struct platform_device *pdev)
 171 {
 172         struct mvebu_pic *pic = platform_get_drvdata(pdev);
 173
 174         on_each_cpu(mvebu_pic_disable_percpu_irq, pic, 1);
 175         irq_domain_remove(pic->domain);
 176
 177         return 0;
 178 }
 179
 180 static const struct of_device_id mvebu_pic_of_match[] = {
 181         { .compatible = "marvell,armada-8k-pic", },
 182         {},
 183 };
 184 MODULE_DEVICE_TABLE(of, mvebu_pic_of_match);
 185
 186 static struct platform_driver mvebu_pic_driver = {
 187         .probe  = mvebu_pic_probe,
 188         .remove = mvebu_pic_remove,
 189         .driver = {
 190                 .name = "mvebu-pic",
 191                 .of_match_table = mvebu_pic_of_match,
 192         },
 193 };
 194 module_platform_driver(mvebu_pic_driver);
 195
 196 MODULE_AUTHOR("Yehuda Yitschak <yehuday@marvell.com>");
 197 MODULE_AUTHOR("Thomas Petazzoni <thomas.petazzoni@free-electrons.com>");
 198 MODULE_LICENSE("GPL v2");
 199 MODULE_ALIAS("platform:mvebu_pic");
 200