xref: /netbsd-src/external/gpl3/gdb/dist/sim/m68hc11/interrupts.h (revision 9b2a9e00295c5af9c57a466f299054d5910e47d6)
1 /* interrupts.h -- 68HC11 Interrupts Emulation
2    Copyright 1999-2024 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   int64_t         taken_cycle;
92 
93   /* CPU cycle when the interrupt is first raised by the device.  */
94   int64_t         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   int64_t         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_t            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   int64_t          start_mask_cycle;
143   int64_t          min_mask_cycles;
144   int64_t          max_mask_cycles;
145   int64_t          last_mask_cycles;
146 
147   /* - Same for XIRQ.  */
148   int64_t          xirq_start_mask_cycle;
149   int64_t          xirq_min_mask_cycles;
150   int64_t          xirq_max_mask_cycles;
151   int64_t          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
174