arch/arm/mach-omap2/irq.c

   1 /*
   2  * linux/arch/arm/mach-omap2/irq.c
   3  *
   4  * Interrupt handler for OMAP2 boards.
   5  *
   6  * Copyright (C) 2005 Nokia Corporation
   7  * Author: Paul Mundt <paul.mundt@nokia.com>
   8  *
   9  * This file is subject to the terms and conditions of the GNU General Public
  10  * License. See the file "COPYING" in the main directory of this archive
  11  * for more details.
  12  */
  13 #include <linux/kernel.h>
  14 #include <linux/init.h>
  15 #include <linux/interrupt.h>
  16 #include <asm/hardware.h>
  17 #include <asm/mach/irq.h>
  18 #include <asm/irq.h>
  19 #include <asm/io.h>
  20
  21 #define INTC_REVISION   0x0000
  22 #define INTC_SYSCONFIG  0x0010
  23 #define INTC_SYSSTATUS  0x0014
  24 #define INTC_CONTROL    0x0048
  25 #define INTC_MIR_CLEAR0 0x0088
  26 #define INTC_MIR_SET0   0x008c
  27
  28 /*
  29  * OMAP2 has a number of different interrupt controllers, each interrupt
  30  * controller is identified as its own "bank". Register definitions are
  31  * fairly consistent for each bank, but not all registers are implemented
  32  * for each bank.. when in doubt, consult the TRM.
  33  */
  34 static struct omap_irq_bank {
  35         unsigned long base_reg;
  36         unsigned int nr_irqs;
  37 } __attribute__ ((aligned(4))) irq_banks[] = {
  38         {
  39                 /* MPU INTC */
  40                 .base_reg       = OMAP24XX_IC_BASE,
  41                 .nr_irqs        = 96,
  42         }, {
  43                 /* XXX: DSP INTC */
  44         }
  45 };
  46
  47 /* XXX: FIQ and additional INTC support (only MPU at the moment) */
  48 static void omap_ack_irq(unsigned int irq)
  49 {
  50         omap_writel(0x1, irq_banks[0].base_reg + INTC_CONTROL);
  51 }
  52
  53 static void omap_mask_irq(unsigned int irq)
  54 {
  55         int offset = (irq >> 5) << 5;
  56
  57         if (irq >= 64) {
  58                 irq %= 64;
  59         } else if (irq >= 32) {
  60                 irq %= 32;
  61         }
  62
  63         omap_writel(1 << irq, irq_banks[0].base_reg + INTC_MIR_SET0 + offset);
  64 }
  65
  66 static void omap_unmask_irq(unsigned int irq)
  67 {
  68         int offset = (irq >> 5) << 5;
  69
  70         if (irq >= 64) {
  71                 irq %= 64;
  72         } else if (irq >= 32) {
  73                 irq %= 32;
  74         }
  75
  76         omap_writel(1 << irq, irq_banks[0].base_reg + INTC_MIR_CLEAR0 + offset);
  77 }
  78
  79 static void omap_mask_ack_irq(unsigned int irq)
  80 {
  81         omap_mask_irq(irq);
  82         omap_ack_irq(irq);
  83 }
  84
  85 static struct irq_chip omap_irq_chip = {
  86         .name   = "INTC",
  87         .ack    = omap_mask_ack_irq,
  88         .mask   = omap_mask_irq,
  89         .unmask = omap_unmask_irq,
  90 };
  91
  92 static void __init omap_irq_bank_init_one(struct omap_irq_bank *bank)
  93 {
  94         unsigned long tmp;
  95
  96         tmp = omap_readl(bank->base_reg + INTC_REVISION) & 0xff;
  97         printk(KERN_INFO "IRQ: Found an INTC at 0x%08lx "
  98                          "(revision %ld.%ld) with %d interrupts\n",
  99                          bank->base_reg, tmp >> 4, tmp & 0xf, bank->nr_irqs);
 100
 101         tmp = omap_readl(bank->base_reg + INTC_SYSCONFIG);
 102         tmp |= 1 << 1;  /* soft reset */
 103         omap_writel(tmp, bank->base_reg + INTC_SYSCONFIG);
 104
 105         while (!(omap_readl(bank->base_reg + INTC_SYSSTATUS) & 0x1))
 106                 /* Wait for reset to complete */;
 107 }
 108
 109 void __init omap_init_irq(void)
 110 {
 111         unsigned long nr_irqs = 0;
 112         unsigned int nr_banks = 0;
 113         int i;
 114
 115         for (i = 0; i < ARRAY_SIZE(irq_banks); i++) {
 116                 struct omap_irq_bank *bank = irq_banks + i;
 117
 118                 /* XXX */
 119                 if (!bank->base_reg)
 120                         continue;
 121
 122                 omap_irq_bank_init_one(bank);
 123
 124                 nr_irqs += bank->nr_irqs;
 125                 nr_banks++;
 126         }
 127
 128         printk(KERN_INFO "Total of %ld interrupts on %d active controller%s\n",
 129                nr_irqs, nr_banks, nr_banks > 1 ? "s" : "");
 130
 131         for (i = 0; i < nr_irqs; i++) {
 132                 set_irq_chip(i, &omap_irq_chip);
 133                 set_irq_handler(i, handle_level_irq);
 134                 set_irq_flags(i, IRQF_VALID);
 135         }
 136 }
 137