arch/sh/boards/mach-systemh/irq.c

   1 /*
   2  * linux/arch/sh/boards/renesas/systemh/irq.c
   3  *
   4  * Copyright (C) 2000  Kazumoto Kojima
   5  *
   6  * Hitachi SystemH Support.
   7  *
   8  * Modified for 7751 SystemH by
   9  * Jonathan Short.
  10  */
  11
  12 #include <linux/init.h>
  13 #include <linux/irq.h>
  14 #include <linux/interrupt.h>
  15 #include <linux/io.h>
  16
  17 #include <mach/systemh7751.h>
  18 #include <asm/smc37c93x.h>
  19
  20 /* address of external interrupt mask register
  21  * address must be set prior to use these (maybe in init_XXX_irq())
  22  * XXX : is it better to use .config than specifying it in code? */
  23 static unsigned long *systemh_irq_mask_register = (unsigned long *)0xB3F10004;
  24 static unsigned long *systemh_irq_request_register = (unsigned long *)0xB3F10000;
  25
  26 /* forward declaration */
  27 static void enable_systemh_irq(unsigned int irq);
  28 static void disable_systemh_irq(unsigned int irq);
  29 static void mask_and_ack_systemh(unsigned int);
  30
  31 static struct irq_chip systemh_irq_type = {
  32         .name = " SystemH Register",
  33         .unmask = enable_systemh_irq,
  34         .mask = disable_systemh_irq,
  35         .ack = mask_and_ack_systemh,
  36 };
  37
  38 static void disable_systemh_irq(unsigned int irq)
  39 {
  40         if (systemh_irq_mask_register) {
  41                 unsigned long val, mask = 0x01 << 1;
  42
  43                 /* Clear the "irq"th bit in the mask and set it in the request */
  44                 val = __raw_readl((unsigned long)systemh_irq_mask_register);
  45                 val &= ~mask;
  46                 __raw_writel(val, (unsigned long)systemh_irq_mask_register);
  47
  48                 val = __raw_readl((unsigned long)systemh_irq_request_register);
  49                 val |= mask;
  50                 __raw_writel(val, (unsigned long)systemh_irq_request_register);
  51         }
  52 }
  53
  54 static void enable_systemh_irq(unsigned int irq)
  55 {
  56         if (systemh_irq_mask_register) {
  57                 unsigned long val, mask = 0x01 << 1;
  58
  59                 /* Set "irq"th bit in the mask register */
  60                 val = __raw_readl((unsigned long)systemh_irq_mask_register);
  61                 val |= mask;
  62                 __raw_writel(val, (unsigned long)systemh_irq_mask_register);
  63         }
  64 }
  65
  66 static void mask_and_ack_systemh(unsigned int irq)
  67 {
  68         disable_systemh_irq(irq);
  69 }
  70
  71 void make_systemh_irq(unsigned int irq)
  72 {
  73         disable_irq_nosync(irq);
  74         set_irq_chip_and_handler(irq, &systemh_irq_type, handle_level_irq);
  75         disable_systemh_irq(irq);
  76 }