xref: /netbsd-src/external/gpl3/gdb.old/dist/sim/bfin/dv-bfin_rtc.c (revision 8b657b0747480f8989760d71343d6dd33f8d4cf9)
1 /* Blackfin Real Time Clock (RTC) model.
2 
3    Copyright (C) 2010-2023 Free Software Foundation, Inc.
4    Contributed by Analog Devices, Inc.
5 
6    This file is part of simulators.
7 
8    This program is free software; you can redistribute it and/or modify
9    it under the terms of the GNU General Public License as published by
10    the Free Software Foundation; either version 3 of the License, or
11    (at your option) any later version.
12 
13    This program is distributed in the hope that it will be useful,
14    but WITHOUT ANY WARRANTY; without even the implied warranty of
15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16    GNU General Public License for more details.
17 
18    You should have received a copy of the GNU General Public License
19    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
20 
21 /* This must come before any other includes.  */
22 #include "defs.h"
23 
24 #include <time.h>
25 #include "sim-main.h"
26 #include "dv-sockser.h"
27 #include "devices.h"
28 #include "dv-bfin_rtc.h"
29 
30 /* XXX: This read-only stub setup is based on host system clock.  */
31 
32 struct bfin_rtc
33 {
34   bu32 base;
35   bu32 stat_shadow;
36 
37   /* Order after here is important -- matches hardware MMR layout.  */
38   bu32 stat;
39   bu16 BFIN_MMR_16(ictl);
40   bu16 BFIN_MMR_16(istat);
41   bu16 BFIN_MMR_16(swcnt);
42   bu32 alarm;
43   bu16 BFIN_MMR_16(pren);
44 };
45 #define mmr_base()      offsetof(struct bfin_rtc, stat)
46 #define mmr_offset(mmr) (offsetof(struct bfin_rtc, mmr) - mmr_base())
47 
48 static const char * const mmr_names[] =
49 {
50   "RTC_STAT", "RTC_ICTL", "RTC_ISTAT", "RTC_SWCNT", "RTC_ALARM", "RTC_PREN",
51 };
52 #define mmr_name(off) mmr_names[(off) / 4]
53 
54 static unsigned
55 bfin_rtc_io_write_buffer (struct hw *me, const void *source,
56 			  int space, address_word addr, unsigned nr_bytes)
57 {
58   struct bfin_rtc *rtc = hw_data (me);
59   bu32 mmr_off;
60   bu32 value;
61   bu16 *value16p;
62   bu32 *value32p;
63   void *valuep;
64 
65   /* Invalid access mode is higher priority than missing register.  */
66   if (!dv_bfin_mmr_require_16_32 (me, addr, nr_bytes, true))
67     return 0;
68 
69   if (nr_bytes == 4)
70     value = dv_load_4 (source);
71   else
72     value = dv_load_2 (source);
73 
74   mmr_off = addr - rtc->base;
75   valuep = (void *)((uintptr_t)rtc + mmr_base() + mmr_off);
76   value16p = valuep;
77   value32p = valuep;
78 
79   HW_TRACE_WRITE ();
80 
81   /* XXX: These probably need more work.  */
82   switch (mmr_off)
83     {
84     case mmr_offset(stat):
85       /* XXX: Ignore these since we are wired to host.  */
86       break;
87     case mmr_offset(istat):
88       dv_w1c_2 (value16p, value, ~(1 << 14));
89       break;
90     case mmr_offset(alarm):
91       break;
92     case mmr_offset(ictl):
93       /* XXX: This should schedule an event handler.  */
94     case mmr_offset(swcnt):
95     case mmr_offset(pren):
96       break;
97     }
98 
99   return nr_bytes;
100 }
101 
102 static unsigned
103 bfin_rtc_io_read_buffer (struct hw *me, void *dest,
104 			 int space, address_word addr, unsigned nr_bytes)
105 {
106   struct bfin_rtc *rtc = hw_data (me);
107   bu32 mmr_off;
108   bu16 *value16p;
109   bu32 *value32p;
110   void *valuep;
111 
112   /* Invalid access mode is higher priority than missing register.  */
113   if (!dv_bfin_mmr_require_16_32 (me, addr, nr_bytes, false))
114     return 0;
115 
116   mmr_off = addr - rtc->base;
117   valuep = (void *)((uintptr_t)rtc + mmr_base() + mmr_off);
118   value16p = valuep;
119   value32p = valuep;
120 
121   HW_TRACE_READ ();
122 
123   switch (mmr_off)
124     {
125     case mmr_offset(stat):
126       {
127 	time_t t = time (NULL);
128 	struct tm *tm = localtime (&t);
129 	bu32 value =
130 	  (((tm->tm_year - 70) * 365 + tm->tm_yday) << 17) |
131 	  (tm->tm_hour << 12) |
132 	  (tm->tm_min << 6) |
133 	  (tm->tm_sec << 0);
134 	dv_store_4 (dest, value);
135 	break;
136       }
137     case mmr_offset(alarm):
138       dv_store_4 (dest, *value32p);
139       break;
140     case mmr_offset(istat):
141     case mmr_offset(ictl):
142     case mmr_offset(swcnt):
143     case mmr_offset(pren):
144       dv_store_2 (dest, *value16p);
145       break;
146     }
147 
148   return nr_bytes;
149 }
150 
151 static const struct hw_port_descriptor bfin_rtc_ports[] =
152 {
153   { "rtc", 0, 0, output_port, },
154   { NULL, 0, 0, 0, },
155 };
156 
157 static void
158 attach_bfin_rtc_regs (struct hw *me, struct bfin_rtc *rtc)
159 {
160   address_word attach_address;
161   int attach_space;
162   unsigned attach_size;
163   reg_property_spec reg;
164 
165   if (hw_find_property (me, "reg") == NULL)
166     hw_abort (me, "Missing \"reg\" property");
167 
168   if (!hw_find_reg_array_property (me, "reg", 0, &reg))
169     hw_abort (me, "\"reg\" property must contain three addr/size entries");
170 
171   hw_unit_address_to_attach_address (hw_parent (me),
172 				     &reg.address,
173 				     &attach_space, &attach_address, me);
174   hw_unit_size_to_attach_size (hw_parent (me), &reg.size, &attach_size, me);
175 
176   if (attach_size != BFIN_MMR_RTC_SIZE)
177     hw_abort (me, "\"reg\" size must be %#x", BFIN_MMR_RTC_SIZE);
178 
179   hw_attach_address (hw_parent (me),
180 		     0, attach_space, attach_address, attach_size, me);
181 
182   rtc->base = attach_address;
183 }
184 
185 static void
186 bfin_rtc_finish (struct hw *me)
187 {
188   struct bfin_rtc *rtc;
189 
190   rtc = HW_ZALLOC (me, struct bfin_rtc);
191 
192   set_hw_data (me, rtc);
193   set_hw_io_read_buffer (me, bfin_rtc_io_read_buffer);
194   set_hw_io_write_buffer (me, bfin_rtc_io_write_buffer);
195   set_hw_ports (me, bfin_rtc_ports);
196 
197   attach_bfin_rtc_regs (me, rtc);
198 
199   /* Initialize the RTC.  */
200 }
201 
202 const struct hw_descriptor dv_bfin_rtc_descriptor[] =
203 {
204   {"bfin_rtc", bfin_rtc_finish,},
205   {NULL, NULL},
206 };
207