drivers/irqchip/irq-renesas-h8300h.c

   1 /*
   2  * H8/300H interrupt controller driver
   3  *
   4  * Copyright 2015 Yoshinori Sato <ysato@users.sourceforge.jp>
   5  */
   6
   7 #include <linux/init.h>
   8 #include <linux/irq.h>
   9 #include <linux/irqchip.h>
  10 #include <linux/of_address.h>
  11 #include <linux/of_irq.h>
  12 #include <asm/io.h>
  13
  14 static const char ipr_bit[] = {
  15          7,  6,  5,  5,
  16          4,  4,  4,  4,  3,  3,  3,  3,
  17          2,  2,  2,  2,  1,  1,  1,  1,
  18          0,  0,  0,  0, 15, 15, 15, 15,
  19         14, 14, 14, 14, 13, 13, 13, 13,
  20         -1, -1, -1, -1, 11, 11, 11, 11,
  21         10, 10, 10, 10,  9,  9,  9,  9,
  22 };
  23
  24 static void __iomem *intc_baseaddr;
  25
  26 #define IPR (intc_baseaddr + 6)
  27
  28 static void h8300h_disable_irq(struct irq_data *data)
  29 {
  30         int bit;
  31         int irq = data->irq - 12;
  32
  33         bit = ipr_bit[irq];
  34         if (bit >= 0) {
  35                 if (bit < 8)
  36                         ctrl_bclr(bit & 7, IPR);
  37                 else
  38                         ctrl_bclr(bit & 7, (IPR+1));
  39         }
  40 }
  41
  42 static void h8300h_enable_irq(struct irq_data *data)
  43 {
  44         int bit;
  45         int irq = data->irq - 12;
  46
  47         bit = ipr_bit[irq];
  48         if (bit >= 0) {
  49                 if (bit < 8)
  50                         ctrl_bset(bit & 7, IPR);
  51                 else
  52                         ctrl_bset(bit & 7, (IPR+1));
  53         }
  54 }
  55
  56 struct irq_chip h8300h_irq_chip = {
  57         .name           = "H8/300H-INTC",
  58         .irq_enable     = h8300h_enable_irq,
  59         .irq_disable    = h8300h_disable_irq,
  60 };
  61
  62 static int irq_map(struct irq_domain *h, unsigned int virq,
  63                    irq_hw_number_t hw_irq_num)
  64 {
  65        irq_set_chip_and_handler(virq, &h8300h_irq_chip, handle_simple_irq);
  66
  67        return 0;
  68 }
  69
  70 static const struct irq_domain_ops irq_ops = {
  71        .map    = irq_map,
  72        .xlate  = irq_domain_xlate_onecell,
  73 };
  74
  75 static int __init h8300h_intc_of_init(struct device_node *intc,
  76                                       struct device_node *parent)
  77 {
  78         struct irq_domain *domain;
  79
  80         intc_baseaddr = of_iomap(intc, 0);
  81         BUG_ON(!intc_baseaddr);
  82
  83         /* All interrupt priority low */
  84         writeb(0x00, IPR + 0);
  85         writeb(0x00, IPR + 1);
  86
  87         domain = irq_domain_add_linear(intc, NR_IRQS, &irq_ops, NULL);
  88         BUG_ON(!domain);
  89         irq_set_default_host(domain);
  90         return 0;
  91 }
  92
  93 IRQCHIP_DECLARE(h8300h_intc, "renesas,h8300h-intc", h8300h_intc_of_init);