target/linux/adm8668/files/arch/mips/adm8668/irq.c

   1 /*
   2  * Copyright (C) 2010 Scott Nicholas <neutronscott@scottn.us>
   3  *
   4  * This file is subject to the terms and conditions of the GNU General Public
   5  * License.  See the file "COPYING" in the main directory of this archive
   6  * for more details.
   7  */
   8
   9 #include <linux/init.h>
  10 #include <linux/kernel_stat.h>
  11 #include <linux/signal.h>
  12 #include <linux/sched.h>
  13 #include <linux/interrupt.h>
  14 #include <linux/slab.h>
  15 #include <linux/random.h>
  16 #include <linux/pm.h>
  17 #include <linux/irq.h>
  18 #include <asm/mipsregs.h>
  19 #include <asm/irq_cpu.h>
  20 #include <asm/irq.h>
  21 #include <adm8668.h>
  22
  23
  24 void enable_adm8668_irq(unsigned int irq);
  25 void disable_adm8668_irq(unsigned int irq);
  26 void adm8668_irq_cascade(void);
  27
  28 void plat_irq_dispatch(void)
  29 {
  30         unsigned int pending;
  31
  32         pending = read_c0_cause() & read_c0_status() & ST0_IM;
  33
  34         /* timer interrupt, that we renumbered */
  35         if (pending & STATUSF_IP7)
  36                 do_IRQ(MIPS_CPU_IRQ_BASE + 7);
  37         if (pending & STATUSF_IP2)
  38                 adm8668_irq_cascade();
  39 }
  40
  41 /*
  42  * System irq dispatch
  43  */
  44 void adm8668_irq_cascade()
  45 {
  46         int i;
  47         unsigned long intsrc;
  48
  49         intsrc = ADM8668_INTC_REG(IRQ_STATUS_REG) & IRQ_MASK;
  50         for (i = 0; intsrc; intsrc >>= 1, i++)
  51                 if (intsrc & 0x1)
  52                         do_IRQ(i);
  53 }
  54
  55 /*
  56  * irq enable
  57  */
  58 static __inline void _irq_enable(int irql)
  59 {
  60         ADM8668_INTC_REG(IRQ_ENABLE_REG) = (1 << irql);
  61 }
  62
  63
  64 /*
  65  * irq disable
  66  */
  67 static __inline void _irq_disable(int irql)
  68 {
  69         ADM8668_INTC_REG(IRQ_DISABLE_REG) = (1 << irql);
  70 }
  71
  72
  73 /*
  74  * enable 8668 irq
  75  */
  76 void enable_adm8668_irq(unsigned int irq)
  77 {
  78         if ((irq < 0) || (irq > NR_IRQS))
  79                 return;
  80
  81         _irq_enable(irq);
  82 }
  83
  84
  85 /*
  86  * disable 8668 irq
  87  */
  88 void disable_adm8668_irq(unsigned int irq)
  89 {
  90         if ((irq < 0) || (irq > NR_IRQS))
  91                 return;
  92
  93         _irq_disable(irq);
  94 }
  95
  96 static inline void ack_adm8668_irq(unsigned int irq_nr)
  97 {
  98         ADM8668_INTC_REG(IRQ_DISABLE_REG) = (1 << irq_nr);
  99 }
 100
 101 /*
 102  * system irq type
 103  */
 104
 105 static struct irq_chip adm8668_irq_type = {
 106         .name = "adm8668",
 107         .ack = ack_adm8668_irq,
 108         .mask = disable_adm8668_irq,
 109         .unmask = enable_adm8668_irq
 110 };
 111
 112 /*
 113  * irq init
 114  */
 115 void __init init_adm8668_irqs(void)
 116 {
 117         int i;
 118
 119         for (i = 0; i <= INT_LVL_MAX; i++)
 120                 set_irq_chip_and_handler(i, &adm8668_irq_type,
 121                         handle_level_irq);
 122
 123         /* hw0 is where our interrupts are uh.. interrupted at. */
 124         set_c0_status(IE_IRQ0);
 125 }
 126
 127 /*
 128  * system init
 129  */
 130 void __init arch_init_irq(void)
 131 {
 132         mips_cpu_irq_init();
 133         init_adm8668_irqs();
 134 }