dev_dreamcast_rtc.cc Source File

Back to the index.

dev_dreamcast_rtc.cc
Go to the documentation of this file.
1 /*
2  * Copyright (C) 2006-2014 Anders Gavare. All rights reserved.
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions are met:
6  *
7  * 1. Redistributions of source code must retain the above copyright
8  * notice, this list of conditions and the following disclaimer.
9  * 2. Redistributions in binary form must reproduce the above copyright
10  * notice, this list of conditions and the following disclaimer in the
11  * documentation and/or other materials provided with the distribution.
12  * 3. The name of the author may not be used to endorse or promote products
13  * derived from this software without specific prior written permission.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  *
27  *
28  * COMMENT: Dreamcast Real-Time Clock
29  *
30  * Pretty basic; two 32-bit words at physical addresses 0x00710000 and
31  * 0x00710004 hold the high and low 16-bit parts, respectively, of the
32  * system's 32-bit tv_sec value.
33  *
34  * The only difference from the raw Unix concept is that the Dreamcast's
35  * clock is based at 1950 instead of 1970.
36  */
37 
38 #include <stdio.h>
39 #include <stdlib.h>
40 #include <string.h>
41 #include <sys/time.h>
42 
43 #include "cpu.h"
44 #include "device.h"
45 #include "machine.h"
46 #include "memory.h"
47 #include "misc.h"
48 
49 
50 #define debug fatal
51 
53  int dummy;
54 };
55 
56 
57 DEVICE_ACCESS(dreamcast_rtc)
58 {
59  /* struct dreamcast_rtc_data *d = extra; */
60  uint64_t idata = 0, odata = 0;
61  struct timeval tv;
62 
63  if (writeflag == MEM_WRITE)
64  idata = memory_readmax64(cpu, data, len);
65 
66  switch (relative_addr) {
67 
68  case 0:
69  case 4:
70  /*
71  * While writing to the RTC could set the date/time of the
72  * host, that would probably be very annoying. For now,
73  * simply ignore writes.
74  */
75  if (writeflag == MEM_WRITE)
76  break;
77 
78  gettimeofday(&tv, NULL);
79 
80  /* Offset by 20 years: */
81  odata = tv.tv_sec + 631152000;
82 
83  if (relative_addr == 0)
84  odata = (odata >> 16) & 0xffff;
85  else
86  odata &= 0xffff;
87  break;
88 
89  case 8:
90  /*
91  * The Dreamcast PROM writes a 1 here when setting the
92  * date/time. Let's ignore it for now.
93  */
94  break;
95 
96  default:
97  if (writeflag == MEM_READ) {
98  fatal("[ dreamcast_rtc: read from addr 0x%x ]\n",
99  (int)relative_addr);
100  } else {
101  fatal("[ dreamcast_rtc: write to addr 0x%x: 0x%x ]\n",
102  (int)relative_addr, (int)idata);
103  }
104  }
105 
106  if (writeflag == MEM_READ)
107  memory_writemax64(cpu, data, len, odata);
108 
109  return 1;
110 }
111 
112 
113 DEVINIT(dreamcast_rtc)
114 {
115  struct dreamcast_rtc_data *d;
116 
117  CHECK_ALLOCATION(d = (struct dreamcast_rtc_data *) malloc(sizeof(struct dreamcast_rtc_data)));
118  memset(d, 0, sizeof(struct dreamcast_rtc_data));
119 
121  0x00710000, 0x100, dev_dreamcast_rtc_access, d, DM_DEFAULT, NULL);
122 
123  return 1;
124 }
125 
uint64_t memory_readmax64(struct cpu *cpu, unsigned char *buf, int len)
Definition: memory.cc:55
DEVINIT(dreamcast_rtc)
void fatal(const char *fmt,...)
Definition: main.cc:152
#define DM_DEFAULT
Definition: memory.h:130
DEVICE_ACCESS(dreamcast_rtc)
char * name
Definition: device.h:43
#define MEM_READ
Definition: memory.h:116
struct memory * memory
Definition: machine.h:126
#define CHECK_ALLOCATION(ptr)
Definition: misc.h:239
u_short data
Definition: siireg.h:79
#define MEM_WRITE
Definition: memory.h:117
Definition: device.h:40
Definition: cpu.h:326
struct machine * machine
Definition: device.h:41
void memory_writemax64(struct cpu *cpu, unsigned char *buf, int len, uint64_t data)
Definition: memory.cc:89
void memory_device_register(struct memory *mem, const char *, uint64_t baseaddr, uint64_t len, int(*f)(struct cpu *, struct memory *, uint64_t, unsigned char *, size_t, int, void *), void *extra, int flags, unsigned char *dyntrans_data)
Definition: memory.cc:339

Generated on Fri Dec 7 2018 19:52:23 for GXemul by doxygen 1.8.13