drivers/irqchip/irq-rda-intc.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * RDA8810PL SoC irqchip driver
   4  *
   5  * Copyright RDA Microelectronics Company Limited
   6  * Copyright (c) 2017 Andreas Färber
   7  * Copyright (c) 2018 Manivannan Sadhasivam
   8  */
   9
  10 #include <linux/init.h>
  11 #include <linux/interrupt.h>
  12 #include <linux/irq.h>
  13 #include <linux/irqchip.h>
  14 #include <linux/irqdomain.h>
  15 #include <linux/of_address.h>
  16
  17 #include <asm/exception.h>
  18
  19 #define RDA_INTC_FINALSTATUS    0x00
  20 #define RDA_INTC_MASK_SET       0x08
  21 #define RDA_INTC_MASK_CLR       0x0c
  22
  23 #define RDA_IRQ_MASK_ALL        0xFFFFFFFF
  24
  25 #define RDA_NR_IRQS 32
  26
  27 static void __iomem *rda_intc_base;
  28 static struct irq_domain *rda_irq_domain;
  29
  30 static void rda_intc_mask_irq(struct irq_data *d)
  31 {
  32         writel_relaxed(BIT(d->hwirq), rda_intc_base + RDA_INTC_MASK_CLR);
  33 }
  34
  35 static void rda_intc_unmask_irq(struct irq_data *d)
  36 {
  37         writel_relaxed(BIT(d->hwirq), rda_intc_base + RDA_INTC_MASK_SET);
  38 }
  39
  40 static int rda_intc_set_type(struct irq_data *data, unsigned int flow_type)
  41 {
  42         /* Hardware supports only level triggered interrupts */
  43         if ((flow_type & (IRQF_TRIGGER_HIGH | IRQF_TRIGGER_LOW)) == flow_type)
  44                 return 0;
  45
  46         return -EINVAL;
  47 }
  48
  49 static void __exception_irq_entry rda_handle_irq(struct pt_regs *regs)
  50 {
  51         u32 stat = readl_relaxed(rda_intc_base + RDA_INTC_FINALSTATUS);
  52         u32 hwirq;
  53
  54         while (stat) {
  55                 hwirq = __fls(stat);
  56                 handle_domain_irq(rda_irq_domain, hwirq, regs);
  57                 stat &= ~BIT(hwirq);
  58         }
  59 }
  60
  61 static struct irq_chip rda_irq_chip = {
  62         .name           = "rda-intc",
  63         .irq_mask       = rda_intc_mask_irq,
  64         .irq_unmask     = rda_intc_unmask_irq,
  65         .irq_set_type   = rda_intc_set_type,
  66 };
  67
  68 static int rda_irq_map(struct irq_domain *d,
  69                        unsigned int virq, irq_hw_number_t hw)
  70 {
  71         irq_set_status_flags(virq, IRQ_LEVEL);
  72         irq_set_chip_and_handler(virq, &rda_irq_chip, handle_level_irq);
  73         irq_set_chip_data(virq, d->host_data);
  74         irq_set_probe(virq);
  75
  76         return 0;
  77 }
  78
  79 static const struct irq_domain_ops rda_irq_domain_ops = {
  80         .map = rda_irq_map,
  81         .xlate = irq_domain_xlate_onecell,
  82 };
  83
  84 static int __init rda8810_intc_init(struct device_node *node,
  85                                     struct device_node *parent)
  86 {
  87         rda_intc_base = of_io_request_and_map(node, 0, "rda-intc");
  88         if (IS_ERR(rda_intc_base))
  89                 return PTR_ERR(rda_intc_base);
  90
  91         /* Mask all interrupt sources */
  92         writel_relaxed(RDA_IRQ_MASK_ALL, rda_intc_base + RDA_INTC_MASK_CLR);
  93
  94         rda_irq_domain = irq_domain_create_linear(&node->fwnode, RDA_NR_IRQS,
  95                                                   &rda_irq_domain_ops,
  96                                                   rda_intc_base);
  97         if (!rda_irq_domain) {
  98                 iounmap(rda_intc_base);
  99                 return -ENOMEM;
 100         }
 101
 102         set_handle_irq(rda_handle_irq);
 103
 104         return 0;
 105 }
 106
 107 IRQCHIP_DECLARE(rda_intc, "rda,8810pl-intc", rda8810_intc_init);