arch/mips/vr41xx/nec-cmbvr4133/irq.c

   1 /*
   2  * arch/mips/vr41xx/nec-cmbvr4133/irq.c
   3  *
   4  * Interrupt routines for the NEC CMB-VR4133 board.
   5  *
   6  * Author: Yoichi Yuasa <yyuasa@mvista.com, or source@mvista.com> and
   7  *         Alex Sapkov <asapkov@ru.mvista.com>
   8  *
   9  * 2003-2004 (c) MontaVista, Software, Inc. This file is licensed under
  10  * the terms of the GNU General Public License version 2. This program
  11  * is licensed "as is" without any warranty of any kind, whether express
  12  * or implied.
  13  *
  14  * Support for NEC-CMBVR4133 in 2.6
  15  * Manish Lachwani (mlachwani@mvista.com)
  16  */
  17 #include <linux/bitops.h>
  18 #include <linux/errno.h>
  19 #include <linux/init.h>
  20 #include <linux/ioport.h>
  21 #include <linux/interrupt.h>
  22
  23 #include <asm/io.h>
  24 #include <asm/vr41xx/cmbvr4133.h>
  25
  26 extern void enable_8259A_irq(unsigned int irq);
  27 extern void disable_8259A_irq(unsigned int irq);
  28 extern void mask_and_ack_8259A(unsigned int irq);
  29 extern void init_8259A(int hoge);
  30
  31 extern int vr4133_rockhopper;
  32
  33 static unsigned int startup_i8259_irq(unsigned int irq)
  34 {
  35         enable_8259A_irq(irq - I8259_IRQ_BASE);
  36         return 0;
  37 }
  38
  39 static void shutdown_i8259_irq(unsigned int irq)
  40 {
  41         disable_8259A_irq(irq - I8259_IRQ_BASE);
  42 }
  43
  44 static void enable_i8259_irq(unsigned int irq)
  45 {
  46         enable_8259A_irq(irq - I8259_IRQ_BASE);
  47 }
  48
  49 static void disable_i8259_irq(unsigned int irq)
  50 {
  51         disable_8259A_irq(irq - I8259_IRQ_BASE);
  52 }
  53
  54 static void ack_i8259_irq(unsigned int irq)
  55 {
  56         mask_and_ack_8259A(irq - I8259_IRQ_BASE);
  57 }
  58
  59 static void end_i8259_irq(unsigned int irq)
  60 {
  61         if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
  62                 enable_8259A_irq(irq - I8259_IRQ_BASE);
  63 }
  64
  65 static struct irq_chip i8259_irq_type = {
  66         .typename       = "XT-PIC",
  67         .startup        = startup_i8259_irq,
  68         .shutdown       = shutdown_i8259_irq,
  69         .enable         = enable_i8259_irq,
  70         .disable        = disable_i8259_irq,
  71         .ack            = ack_i8259_irq,
  72         .end            = end_i8259_irq,
  73 };
  74
  75 static int i8259_get_irq_number(int irq)
  76 {
  77         unsigned long isr;
  78
  79         isr = inb(0x20);
  80         irq = ffz(~isr);
  81         if (irq == 2) {
  82                 isr = inb(0xa0);
  83                 irq = 8 + ffz(~isr);
  84         }
  85
  86         if (irq < 0 || irq > 15)
  87                 return -EINVAL;
  88
  89         return I8259_IRQ_BASE + irq;
  90 }
  91
  92 static struct irqaction i8259_slave_cascade = {
  93         .handler        = &no_action,
  94         .name           = "cascade",
  95 };
  96
  97 void __init rockhopper_init_irq(void)
  98 {
  99         int i;
 100
 101         if(!vr4133_rockhopper) {
 102                 printk(KERN_ERR "Not a Rockhopper Board \n");
 103                 return;
 104         }
 105
 106         for (i = I8259_IRQ_BASE; i <= I8259_IRQ_LAST; i++)
 107                 irq_desc[i].chip = &i8259_irq_type;
 108
 109         setup_irq(I8259_SLAVE_IRQ, &i8259_slave_cascade);
 110
 111         vr41xx_set_irq_trigger(CMBVR41XX_INTC_PIN, TRIGGER_LEVEL, SIGNAL_THROUGH);
 112         vr41xx_set_irq_level(CMBVR41XX_INTC_PIN, LEVEL_HIGH);
 113         vr41xx_cascade_irq(CMBVR41XX_INTC_IRQ, i8259_get_irq_number);
 114 }