summaryrefslogtreecommitdiffstats
path: root/nuttx/arch/arm/src/lpc2378/lpc23xx_decodeirq.c
blob: 100502a2218ca08aabccaaab1aa7c067199f223c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
/********************************************************************************
 * arch/arm/src/lpc2378/lpc23xx_decodeirq.c
 *
 *   Copyright (C) 2010 Rommel Marcelo. All rights reserved.
 *   Author: Rommel Marcelo
 *
 * This file is part of the NuttX RTOS and based on the lpc2148 port:
 *
 *   Copyright (C) 2010, 2011 Gregory Nutt. All rights reserved.
 *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 * 3. Neither the name NuttX nor the names of its contributors may be
 *    used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 ********************************************************************************/

/********************************************************************************
 * Included Files
 ********************************************************************************/

#include <nuttx/config.h>

#include <sys/types.h>
#include <stdint.h>
#include <nuttx/irq.h>
#include <nuttx/arch.h>
#include <assert.h>
#include <debug.h>

#include <arch/board/board.h>

#include "up_arch.h"
#include "os_internal.h"
#include "internal.h"
#include "lpc23xx_vic.h"

/********************************************************************************
 * Definitions
 ********************************************************************************/

/********************************************************************************
 * Private Types
 ********************************************************************************/

/********************************************************************************
 * Public Data
 ********************************************************************************/

/********************************************************************************
 * Private Data
 ********************************************************************************/

/********************************************************************************
 * Private Functions
 ********************************************************************************/

/********************************************************************************
 * Public Funstions
 ********************************************************************************/

/********************************************************************************
 * up_decodeirq() and/or lpc23xx_decodeirq()
 *
 * Description:
 *   The vectored interrupt controller (VIC) takes 32 interrupt request inputs
 *   and programmatically assigns them into 2 categories:  FIQ, vectored IRQ.
 *
 *   - FIQs have the highest priority.  There is a single FIQ vector, but multiple
 *     interrupt sources can be ORed to this FIQ vector.
 *
 *   - Vectored IRQs have the middle priority.  Any of the 32 interrupt sources
 *     can be assigned to vectored IRQs.
 *
 *   - Non-vectored IRQs have the lowest priority.
 *
 *   The general flow of IRQ processing is to simply read the VICAddress
 *   and jump to the address of the vector provided in the register.  The VIC will
 *   provide the address of the highest priority vectored IRQ.  If a non-vectored
 *   IRQ is requesting, the address of a default handler is provided.
 *
 ********************************************************************************/

#ifndef CONFIG_VECTORED_INTERRUPTS
void up_decodeirq(uint32_t *regs)
#else
static void lpc23xx_decodeirq(uint32_t *regs)
#endif
{
#ifdef CONFIG_SUPPRESS_INTERRUPTS
  lib_lowprintf("Unexpected IRQ\n");
  current_regs = regs;
  PANIC(OSERR_ERREXCEPTION);
#else

  /* Check which IRQ fires */

  uint32_t irqbits = vic_getreg(VIC_IRQSTATUS_OFFSET) & 0xFFFFFFFF;
  unsigned int irq;

  for (irq = 0; irq < NR_IRQS; irq++)
    {
      if (irqbits & (uint32_t) (1 << irq))
        break;
    }

  /* Verify that the resulting IRQ number is valid */

  if (irq < NR_IRQS)            /* redundant check ?? */
    {
       uint32_t *savestate;

      /* Current regs non-zero indicates that we are processing an interrupt;
       * current_regs is also used to manage interrupt level context switches.
       */

      savestate    = (uint32_t*)current_regs;
      current_regs = regs;

      /* Mask and acknowledge the interrupt */

      up_maskack_irq(irq);

      /* Deliver the IRQ */

      irq_dispatch(irq, regs);

      /* Restore the previous value of current_regs.  NULL would indicate that
       * we are no longer in an interrupt handler.  It will be non-NULL if we
       * are returning from a nested interrupt.
       */

      current_regs = savestate;
    }

#endif
}

#ifdef CONFIG_VECTORED_INTERRUPTS
void up_decodeirq(uint32_t *regs)
{
  vic_vector_t vector = (vic_vector_t) vic_getreg(VIC_ADDRESS_OFFSET);

  /* Mask and acknowledge the interrupt */

  up_maskack_irq(irq);

  /* Valid Interrupt */

  if (vector != NULL)
    (vector) (regs);
}
#endif