sim/m68hc11/interrupts.h

   1 /* interrupts.h -- 68HC11 Interrupts Emulation
   2    Copyright 1999-2019 Free Software Foundation, Inc.
   3    Written by Stephane Carrez (stcarrez@worldnet.fr)
   4
   5 This file is part of GDB, GAS, and the GNU binutils.
   6
   7 This program is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 3 of the License, or
  10 (at your option) any later version.
  11
  12 This program is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #ifndef _M6811_SIM_INTERRUPTS_H
  21 #define _M6811_SIM_INTERRUPTS_H
  22
  23 /* Definition of 68HC11 interrupts.  These enum are used as an index
  24    in the interrupt table.  */
  25 enum M6811_INT
  26 {
  27   M6811_INT_RESERVED1 = 0,
  28   M6811_INT_RESERVED2,
  29   M6811_INT_RESERVED3,
  30   M6811_INT_RESERVED4,
  31   M6811_INT_RESERVED5,
  32   M6811_INT_RESERVED6,
  33   M6811_INT_RESERVED7,
  34   M6811_INT_RESERVED8,
  35
  36   M6811_INT_RESERVED9,
  37   M6811_INT_RESERVED10,
  38   M6811_INT_RESERVED11,
  39
  40   M6811_INT_SCI,
  41   M6811_INT_SPI,
  42   M6811_INT_AINPUT,
  43   M6811_INT_AOVERFLOW,
  44   M6811_INT_TCTN,
  45
  46   M6811_INT_OUTCMP5,
  47   M6811_INT_OUTCMP4,
  48   M6811_INT_OUTCMP3,
  49   M6811_INT_OUTCMP2,
  50   M6811_INT_OUTCMP1,
  51
  52   M6811_INT_INCMP3,
  53   M6811_INT_INCMP2,
  54   M6811_INT_INCMP1,
  55
  56   M6811_INT_RT,
  57   M6811_INT_IRQ,
  58   M6811_INT_XIRQ,
  59   M6811_INT_SWI,
  60   M6811_INT_ILLEGAL,
  61
  62   M6811_INT_COPRESET,
  63   M6811_INT_COPFAIL,
  64
  65   M6811_INT_RESET,
  66   M6811_INT_NUMBER
  67 };
  68
  69
  70 /* Structure to describe how to recognize an interrupt in the
  71    68hc11 IO regs.  */
  72 struct interrupt_def
  73 {
  74   enum M6811_INT   int_number;
  75   unsigned char    int_paddr;
  76   unsigned char    int_mask;
  77   unsigned char    enable_paddr;
  78   unsigned char    enabled_mask;
  79 };
  80
  81 #define MAX_INT_HISTORY 64
  82
  83 /* Structure used to keep track of interrupt history.
  84    This is used to understand in which order interrupts were
  85    raised and when.  */
  86 struct interrupt_history
  87 {
  88   enum M6811_INT   type;
  89
  90   /* CPU cycle when interrupt handler is called.  */
  91   signed64         taken_cycle;
  92
  93   /* CPU cycle when the interrupt is first raised by the device.  */
  94   signed64         raised_cycle;
  95 };
  96
  97 #define SIM_STOP_WHEN_RAISED 1
  98 #define SIM_STOP_WHEN_TAKEN  2
  99
 100 /* Information and control of pending interrupts.  */
 101 struct interrupt
 102 {
 103   /* CPU cycle when the interrupt is raised by the device.  */
 104   signed64         cpu_cycle;
 105
 106   /* Number of times the interrupt was raised.  */
 107   unsigned long    raised_count;
 108
 109   /* Controls whether we must stop the simulator.  */
 110   int              stop_mode;
 111 };
 112
 113
 114 /* Management of 68HC11 interrupts:
 115     - We use a table of 'interrupt_def' to describe the interrupts that must be
 116       raised depending on IO register flags (enable and present flags).
 117     - We keep a mask of pending interrupts.  This mask is refreshed by
 118       calling 'interrupts_update_pending'.  It must be refreshed each time
 119       an IO register is changed.
 120     - 'interrupts_process' must be called after each insn. It has two purposes:
 121       first it maintains a min/max count of CPU cycles between which interrupts
 122       are masked; second it checks for pending interrupts and raise one if
 123       interrupts are enabled.  */
 124 struct interrupts {
 125   sim_cpu           *cpu;
 126
 127   /* Mask of current pending interrupts.  */
 128   unsigned long     pending_mask;
 129
 130   /* Address of vector table.  This is set depending on the
 131      68hc11 init mode.  */
 132   uint16            vectors_addr;
 133
 134   /* Priority order of interrupts.  This is controlled by setting the HPRIO
 135      IO register.  */
 136   enum M6811_INT    interrupt_order[M6811_INT_NUMBER];
 137   struct interrupt  interrupts[M6811_INT_NUMBER];
 138
 139   /* Simulator statistics to report useful debug information to users.  */
 140
 141   /* - Max/Min number of CPU cycles executed with interrupts masked.  */
 142   signed64          start_mask_cycle;
 143   signed64          min_mask_cycles;
 144   signed64          max_mask_cycles;
 145   signed64          last_mask_cycles;
 146
 147   /* - Same for XIRQ.  */
 148   signed64          xirq_start_mask_cycle;
 149   signed64          xirq_min_mask_cycles;
 150   signed64          xirq_max_mask_cycles;
 151   signed64          xirq_last_mask_cycles;
 152
 153   /* - Total number of interrupts raised.  */
 154   unsigned long     nb_interrupts_raised;
 155
 156   /* Interrupt history to help understand which interrupts
 157      were raised recently and in which order.  */
 158   int               history_index;
 159   struct interrupt_history interrupts_history[MAX_INT_HISTORY];
 160 };
 161
 162 extern void interrupts_initialize     (SIM_DESC sd, sim_cpu *cpu);
 163 extern void interrupts_reset          (struct interrupts* interrupts);
 164 extern void interrupts_update_pending (struct interrupts* interrupts);
 165 extern int  interrupts_get_current    (struct interrupts* interrupts);
 166 extern int  interrupts_process        (struct interrupts* interrupts);
 167 extern void interrupts_raise          (struct interrupts* interrupts,
 168                                        enum M6811_INT number);
 169
 170 extern void interrupts_info           (SIM_DESC sd,
 171                                        struct interrupts* interrupts);
 172
 173 #endif