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 static DEFINE_SPINLOCK(r4030_lock);
  19
  20 static void enable_r4030_irq(unsigned int irq)
  21 {
  22         unsigned int mask = 1 << (irq - JAZZ_PARALLEL_IRQ);
  23         unsigned long flags;
  24
  25         spin_lock_irqsave(&r4030_lock, flags);
  26         mask |= r4030_read_reg16(JAZZ_IO_IRQ_ENABLE);
  27         r4030_write_reg16(JAZZ_IO_IRQ_ENABLE, mask);
  28         spin_unlock_irqrestore(&r4030_lock, flags);
  29 }
  30
  31 void disable_r4030_irq(unsigned int irq)
  32 {
  33         unsigned int mask = ~(1 << (irq - JAZZ_PARALLEL_IRQ));
  34         unsigned long flags;
  35
  36         spin_lock_irqsave(&r4030_lock, flags);
  37         mask &= r4030_read_reg16(JAZZ_IO_IRQ_ENABLE);
  38         r4030_write_reg16(JAZZ_IO_IRQ_ENABLE, mask);
  39         spin_unlock_irqrestore(&r4030_lock, flags);
  40 }
  41
  42 static struct irq_chip r4030_irq_type = {
  43         .typename = "R4030",
  44         .ack = disable_r4030_irq,
  45         .mask = disable_r4030_irq,
  46         .mask_ack = disable_r4030_irq,
  47         .unmask = enable_r4030_irq,
  48 };
  49
  50 void __init init_r4030_ints(void)
  51 {
  52         int i;
  53
  54         for (i = JAZZ_PARALLEL_IRQ; i <= JAZZ_TIMER_IRQ; i++)
  55                 set_irq_chip_and_handler(i, &r4030_irq_type, handle_level_irq);
  56
  57         r4030_write_reg16(JAZZ_IO_IRQ_ENABLE, 0);
  58         r4030_read_reg16(JAZZ_IO_IRQ_SOURCE);           /* clear pending IRQs */
  59         r4030_read_reg32(JAZZ_R4030_INVAL_ADDR);        /* clear error bits */
  60 }
  61
  62 /*
  63  * On systems with i8259-style interrupt controllers we assume for
  64  * driver compatibility reasons interrupts 0 - 15 to be the i8259
  65  * interrupts even if the hardware uses a different interrupt numbering.
  66  */
  67 void __init arch_init_irq(void)
  68 {
  69         init_i8259_irqs();                      /* Integrated i8259  */
  70         init_r4030_ints();
  71
  72         change_c0_status(ST0_IM, IE_IRQ4 | IE_IRQ3 | IE_IRQ2 | IE_IRQ1);
  73 }
  74
  75 static void loc_call(unsigned int irq, unsigned int mask)
  76 {
  77         r4030_write_reg16(JAZZ_IO_IRQ_ENABLE,
  78                           r4030_read_reg16(JAZZ_IO_IRQ_ENABLE) & mask);
  79         do_IRQ(irq);
  80         r4030_write_reg16(JAZZ_IO_IRQ_ENABLE,
  81                           r4030_read_reg16(JAZZ_IO_IRQ_ENABLE) | mask);
  82 }
  83
  84 static void ll_local_dev(void)
  85 {
  86         switch (r4030_read_reg32(JAZZ_IO_IRQ_SOURCE)) {
  87         case 0:
  88                 panic("Unimplemented loc_no_irq handler");
  89                 break;
  90         case 4:
  91                 loc_call(JAZZ_PARALLEL_IRQ, JAZZ_IE_PARALLEL);
  92                 break;
  93         case 8:
  94                 loc_call(JAZZ_PARALLEL_IRQ, JAZZ_IE_FLOPPY);
  95                 break;
  96         case 12:
  97                 panic("Unimplemented loc_sound handler");
  98                 break;
  99         case 16:
 100                 panic("Unimplemented loc_video handler");
 101                 break;
 102         case 20:
 103                 loc_call(JAZZ_ETHERNET_IRQ, JAZZ_IE_ETHERNET);
 104                 break;
 105         case 24:
 106                 loc_call(JAZZ_SCSI_IRQ, JAZZ_IE_SCSI);
 107                 break;
 108         case 28:
 109                 loc_call(JAZZ_KEYBOARD_IRQ, JAZZ_IE_KEYBOARD);
 110                 break;
 111         case 32:
 112                 loc_call(JAZZ_MOUSE_IRQ, JAZZ_IE_MOUSE);
 113                 break;
 114         case 36:
 115                 loc_call(JAZZ_SERIAL1_IRQ, JAZZ_IE_SERIAL1);
 116                 break;
 117         case 40:
 118                 loc_call(JAZZ_SERIAL2_IRQ, JAZZ_IE_SERIAL2);
 119                 break;
 120         }
 121 }
 122
 123 asmlinkage void plat_irq_dispatch(void)
 124 {
 125         unsigned int pending = read_c0_cause() & read_c0_status() & ST0_IM;
 126
 127         if (pending & IE_IRQ5)
 128                 write_c0_compare(0);
 129         else if (pending & IE_IRQ4) {
 130                 r4030_read_reg32(JAZZ_TIMER_REGISTER);
 131                 do_IRQ(JAZZ_TIMER_IRQ);
 132         } else if (pending & IE_IRQ3)
 133                 panic("Unimplemented ISA NMI handler");
 134         else if (pending & IE_IRQ2)
 135                 do_IRQ(r4030_read_reg32(JAZZ_EISA_IRQ_ACK));
 136         else if (pending & IE_IRQ1) {
 137                 ll_local_dev();
 138         } else if (unlikely(pending & IE_IRQ0))
 139                 panic("Unimplemented local_dma handler");
 140         else if (pending & IE_SW1) {
 141                 clear_c0_cause(IE_SW1);
 142                 panic("Unimplemented sw1 handler");
 143         } else if (pending & IE_SW0) {
 144                 clear_c0_cause(IE_SW0);
 145                 panic("Unimplemented sw0 handler");
 146         }
 147 }