release/src-rt-6.x/linux/linux-2.6/arch/arm/common/vic.c

   1 /*
   2  *  linux/arch/arm/common/vic.c
   3  *
   4  *  Copyright (C) 1999 - 2003 ARM Limited
   5  *  Copyright (C) 2000 Deep Blue Solutions Ltd
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  20  */
  21 #include <linux/init.h>
  22 #include <linux/list.h>
  23
  24 #include <asm/io.h>
  25 #include <asm/mach/irq.h>
  26 #include <asm/hardware/vic.h>
  27
  28 static void vic_mask_irq(unsigned int irq)
  29 {
  30         void __iomem *base = get_irq_chip_data(irq);
  31         irq &= 31;
  32         writel(1 << irq, base + VIC_INT_ENABLE_CLEAR);
  33 }
  34
  35 static void vic_unmask_irq(unsigned int irq)
  36 {
  37         void __iomem *base = get_irq_chip_data(irq);
  38         irq &= 31;
  39         writel(1 << irq, base + VIC_INT_ENABLE);
  40 }
  41
  42 static struct irq_chip vic_chip = {
  43         .name   = "VIC",
  44         .ack    = vic_mask_irq,
  45         .mask   = vic_mask_irq,
  46         .unmask = vic_unmask_irq,
  47 };
  48
  49 /**
  50  * vic_init - initialise a vectored interrupt controller
  51  * @base: iomem base address
  52  * @irq_start: starting interrupt number, must be muliple of 32
  53  * @vic_sources: bitmask of interrupt sources to allow
  54  */
  55 void __init vic_init(void __iomem *base, unsigned int irq_start,
  56                      u32 vic_sources)
  57 {
  58         unsigned int i;
  59
  60         /* Disable all interrupts initially. */
  61
  62         writel(0, base + VIC_INT_SELECT);
  63         writel(0, base + VIC_INT_ENABLE);
  64         writel(~0, base + VIC_INT_ENABLE_CLEAR);
  65         writel(0, base + VIC_IRQ_STATUS);
  66         writel(0, base + VIC_ITCR);
  67         writel(~0, base + VIC_INT_SOFT_CLEAR);
  68
  69         /*
  70          * Make sure we clear all existing interrupts
  71          */
  72         writel(0, base + VIC_VECT_ADDR);
  73         for (i = 0; i < 19; i++) {
  74                 unsigned int value;
  75
  76                 value = readl(base + VIC_VECT_ADDR);
  77                 writel(value, base + VIC_VECT_ADDR);
  78         }
  79
  80         for (i = 0; i < 16; i++) {
  81                 void __iomem *reg = base + VIC_VECT_CNTL0 + (i * 4);
  82                 writel(VIC_VECT_CNTL_ENABLE | i, reg);
  83         }
  84
  85         writel(32, base + VIC_DEF_VECT_ADDR);
  86
  87         for (i = 0; i < 32; i++) {
  88                 unsigned int irq = irq_start + i;
  89
  90                 set_irq_chip(irq, &vic_chip);
  91                 set_irq_chip_data(irq, base);
  92
  93                 if (vic_sources & (1 << i)) {
  94                         set_irq_handler(irq, handle_level_irq);
  95                         set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
  96                 }
  97         }
  98 }