arch/mips/jazz/irq.c

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * Copyright (C) 1992 Linus Torvalds
   7  * Copyright (C) 1994 - 2001, 2003 Ralf Baechle
   8  */
   9 #include <linux/init.h>
  10 #include <linux/interrupt.h>
  11 #include <linux/kernel.h>
  12 #include <linux/spinlock.h>
  13
  14 #include <asm/i8259.h>
  15 #include <asm/io.h>
  16 #include <asm/jazz.h>
  17
  18 extern asmlinkage void jazz_handle_int(void);
  19
  20 static spinlock_t r4030_lock = SPIN_LOCK_UNLOCKED;
  21
  22 extern asmlinkage void sni_rm200_pci_handle_int(void);
  23
  24 static void enable_r4030_irq(unsigned int irq)
  25 {
  26         unsigned int mask = 1 << (irq - JAZZ_IE_PARALLEL);
  27         unsigned long flags;
  28
  29         spin_lock_irqsave(&r4030_lock, flags);
  30         mask |= r4030_read_reg16(JAZZ_IO_IRQ_ENABLE);
  31         r4030_write_reg16(JAZZ_IO_IRQ_ENABLE, mask);
  32         spin_unlock_irqrestore(&r4030_lock, flags);
  33 }
  34
  35 static unsigned int startup_r4030_irq(unsigned int irq)
  36 {
  37         enable_r4030_irq(irq);
  38         return 0; /* never anything pending */
  39 }
  40
  41 #define shutdown_r4030_irq      disable_r4030_irq
  42
  43 void disable_r4030_irq(unsigned int irq)
  44 {
  45         unsigned int mask = ~(1 << (irq - JAZZ_IE_PARALLEL));
  46         unsigned long flags;
  47
  48         spin_lock_irqsave(&r4030_lock, flags);
  49         mask &= r4030_read_reg16(JAZZ_IO_IRQ_ENABLE);
  50         r4030_write_reg16(JAZZ_IO_IRQ_ENABLE, mask);
  51         spin_unlock_irqrestore(&r4030_lock, flags);
  52 }
  53
  54 #define mask_and_ack_r4030_irq disable_r4030_irq
  55
  56 static void end_r4030_irq(unsigned int irq)
  57 {
  58         if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
  59                 enable_r4030_irq(irq);
  60 }
  61
  62 static struct hw_interrupt_type r4030_irq_type = {
  63         "R4030",
  64         startup_r4030_irq,
  65         shutdown_r4030_irq,
  66         enable_r4030_irq,
  67         disable_r4030_irq,
  68         mask_and_ack_r4030_irq,
  69         end_r4030_irq,
  70         NULL
  71 };
  72
  73 void __init init_r4030_ints(void)
  74 {
  75         int i;
  76
  77         for (i = JAZZ_PARALLEL_IRQ; i <= JAZZ_TIMER_IRQ; i++) {
  78                 irq_desc[i].status     = IRQ_DISABLED;
  79                 irq_desc[i].action     = 0;
  80                 irq_desc[i].depth      = 1;
  81                 irq_desc[i].handler    = &r4030_irq_type;
  82         }
  83
  84         r4030_write_reg16(JAZZ_IO_IRQ_ENABLE, 0);
  85         r4030_read_reg16(JAZZ_IO_IRQ_SOURCE);           /* clear pending IRQs */
  86         r4030_read_reg32(JAZZ_R4030_INVAL_ADDR);        /* clear error bits */
  87 }
  88
  89 /*
  90  * On systems with i8259-style interrupt controllers we assume for
  91  * driver compatibility reasons interrupts 0 - 15 to be the i8259
  92  * interrupts even if the hardware uses a different interrupt numbering.
  93  */
  94 void __init init_IRQ (void)
  95 {
  96         set_except_vector(0, jazz_handle_int);
  97
  98         init_generic_irq();
  99         init_i8259_irqs();                      /* Integrated i8259  */
 100         init_r4030_ints();
 101
 102         change_c0_status(ST0_IM, IE_IRQ4 | IE_IRQ3 | IE_IRQ2 | IE_IRQ1);
 103 }