arch/arm/mach-s3c2410/bast-irq.c

   1 /* linux/arch/arm/mach-s3c2410/bast-irq.c
   2  *
   3  * Copyright (c) 2004 Simtec Electronics
   4  *   Ben Dooks <ben@simtec.co.uk>
   5  *
   6  * http://www.simtec.co.uk/products/EB2410ITX/
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  21  *
  22  * Modifications:
  23  *     08-Jan-2003 BJD  Moved from central IRQ code
  24  */
  25
  26
  27 #include <linux/init.h>
  28 #include <linux/module.h>
  29 #include <linux/ioport.h>
  30 #include <linux/ptrace.h>
  31 #include <linux/sysdev.h>
  32
  33 #include <asm/hardware.h>
  34 #include <asm/irq.h>
  35 #include <asm/io.h>
  36
  37 #include <asm/mach/irq.h>
  38 #include <asm/hardware/s3c2410/irq.h>
  39
  40 #if 0
  41 #include <asm/debug-ll.h>
  42 #endif
  43
  44 #define irqdbf(x...)
  45 #define irqdbf2(x...)
  46
  47
  48 /* handle PC104 ISA interrupts from the system CPLD */
  49
  50 /* table of ISA irq nos to the relevant mask... zero means
  51  * the irq is not implemented
  52 */
  53 static unsigned char bast_pc104_irqmasks[] = {
  54         0,   /* 0 */
  55         0,   /* 1 */
  56         0,   /* 2 */
  57         1,   /* 3 */
  58         0,   /* 4 */
  59         2,   /* 5 */
  60         0,   /* 6 */
  61         4,   /* 7 */
  62         0,   /* 8 */
  63         0,   /* 9 */
  64         8,   /* 10 */
  65         0,   /* 11 */
  66         0,   /* 12 */
  67         0,   /* 13 */
  68         0,   /* 14 */
  69         0,   /* 15 */
  70 };
  71
  72 static unsigned char bast_pc104_irqs[] = { 3, 5, 7, 10 };
  73
  74 static void
  75 bast_pc104_mask(unsigned int irqno)
  76 {
  77         unsigned long temp;
  78
  79         temp = __raw_readb(BAST_VA_PC104_IRQMASK);
  80         temp &= ~bast_pc104_irqmasks[irqno];
  81         __raw_writeb(temp, BAST_VA_PC104_IRQMASK);
  82
  83         if (temp == 0)
  84                 bast_extint_mask(IRQ_ISA);
  85 }
  86
  87 static void
  88 bast_pc104_ack(unsigned int irqno)
  89 {
  90         bast_extint_ack(IRQ_ISA);
  91 }
  92
  93 static void
  94 bast_pc104_unmask(unsigned int irqno)
  95 {
  96         unsigned long temp;
  97
  98         temp = __raw_readb(BAST_VA_PC104_IRQMASK);
  99         temp |= bast_pc104_irqmasks[irqno];
 100         __raw_writeb(temp, BAST_VA_PC104_IRQMASK);
 101
 102         bast_extint_unmask(IRQ_ISA);
 103 }
 104
 105 static struct bast_pc104_chip = {
 106         .mask        = bast_pc104_mask,
 107         .unmask      = bast_pc104_unmask,
 108         .ack         = bast_pc104_ack
 109 };
 110
 111 static void
 112 bast_irq_pc104_demux(unsigned int irq,
 113                      struct irqdesc *desc,
 114                      struct pt_regs *regs)
 115 {
 116         unsigned int stat;
 117         unsigned int irqno;
 118         int i;
 119
 120         stat = __raw_readb(BAST_VA_PC104_IRQREQ) & 0xf;
 121
 122         for (i = 0; i < 4 && stat != 0; i++) {
 123                 if (stat & 1) {
 124                         irqno = bast_pc104_irqs[i];
 125                         desc = irq_desc + irqno;
 126
 127                         desc->handle(irqno, desc, regs);
 128                 }
 129
 130                 stat >>= 1;
 131         }
 132 }