sim/bfin/dv-bfin_rtc.c

   1 /* Blackfin Real Time Clock (RTC) model.
   2
   3    Copyright (C) 2010-2024 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   void *valuep;
  63
  64   /* Invalid access mode is higher priority than missing register.  */
  65   if (!dv_bfin_mmr_require_16_32 (me, addr, nr_bytes, true))
  66     return 0;
  67
  68   if (nr_bytes == 4)
  69     value = dv_load_4 (source);
  70   else
  71     value = dv_load_2 (source);
  72
  73   mmr_off = addr - rtc->base;
  74   valuep = (void *)((uintptr_t)rtc + mmr_base() + mmr_off);
  75   value16p = valuep;
  76
  77   HW_TRACE_WRITE ();
  78
  79   /* XXX: These probably need more work.  */
  80   switch (mmr_off)
  81     {
  82     case mmr_offset(stat):
  83       /* XXX: Ignore these since we are wired to host.  */
  84       break;
  85     case mmr_offset(istat):
  86       dv_w1c_2 (value16p, value, ~(1 << 14));
  87       break;
  88     case mmr_offset(alarm):
  89       break;
  90     case mmr_offset(ictl):
  91       /* XXX: This should schedule an event handler.  */
  92     case mmr_offset(swcnt):
  93     case mmr_offset(pren):
  94       break;
  95     }
  96
  97   return nr_bytes;
  98 }
  99
 100 static unsigned
 101 bfin_rtc_io_read_buffer (struct hw *me, void *dest,
 102                          int space, address_word addr, unsigned nr_bytes)
 103 {
 104   struct bfin_rtc *rtc = hw_data (me);
 105   bu32 mmr_off;
 106   bu16 *value16p;
 107   bu32 *value32p;
 108   void *valuep;
 109
 110   /* Invalid access mode is higher priority than missing register.  */
 111   if (!dv_bfin_mmr_require_16_32 (me, addr, nr_bytes, false))
 112     return 0;
 113
 114   mmr_off = addr - rtc->base;
 115   valuep = (void *)((uintptr_t)rtc + mmr_base() + mmr_off);
 116   value16p = valuep;
 117   value32p = valuep;
 118
 119   HW_TRACE_READ ();
 120
 121   switch (mmr_off)
 122     {
 123     case mmr_offset(stat):
 124       {
 125         time_t t = time (NULL);
 126         struct tm *tm = localtime (&t);
 127         bu32 value =
 128           (((tm->tm_year - 70) * 365 + tm->tm_yday) << 17) |
 129           (tm->tm_hour << 12) |
 130           (tm->tm_min << 6) |
 131           (tm->tm_sec << 0);
 132         dv_store_4 (dest, value);
 133         break;
 134       }
 135     case mmr_offset(alarm):
 136       dv_store_4 (dest, *value32p);
 137       break;
 138     case mmr_offset(istat):
 139     case mmr_offset(ictl):
 140     case mmr_offset(swcnt):
 141     case mmr_offset(pren):
 142       dv_store_2 (dest, *value16p);
 143       break;
 144     }
 145
 146   return nr_bytes;
 147 }
 148
 149 static const struct hw_port_descriptor bfin_rtc_ports[] =
 150 {
 151   { "rtc", 0, 0, output_port, },
 152   { NULL, 0, 0, 0, },
 153 };
 154
 155 static void
 156 attach_bfin_rtc_regs (struct hw *me, struct bfin_rtc *rtc)
 157 {
 158   address_word attach_address;
 159   int attach_space;
 160   unsigned attach_size;
 161   reg_property_spec reg;
 162
 163   if (hw_find_property (me, "reg") == NULL)
 164     hw_abort (me, "Missing \"reg\" property");
 165
 166   if (!hw_find_reg_array_property (me, "reg", 0, &reg))
 167     hw_abort (me, "\"reg\" property must contain three addr/size entries");
 168
 169   hw_unit_address_to_attach_address (hw_parent (me),
 170                                      &reg.address,
 171                                      &attach_space, &attach_address, me);
 172   hw_unit_size_to_attach_size (hw_parent (me), &reg.size, &attach_size, me);
 173
 174   if (attach_size != BFIN_MMR_RTC_SIZE)
 175     hw_abort (me, "\"reg\" size must be %#x", BFIN_MMR_RTC_SIZE);
 176
 177   hw_attach_address (hw_parent (me),
 178                      0, attach_space, attach_address, attach_size, me);
 179
 180   rtc->base = attach_address;
 181 }
 182
 183 static void
 184 bfin_rtc_finish (struct hw *me)
 185 {
 186   struct bfin_rtc *rtc;
 187
 188   rtc = HW_ZALLOC (me, struct bfin_rtc);
 189
 190   set_hw_data (me, rtc);
 191   set_hw_io_read_buffer (me, bfin_rtc_io_read_buffer);
 192   set_hw_io_write_buffer (me, bfin_rtc_io_write_buffer);
 193   set_hw_ports (me, bfin_rtc_ports);
 194
 195   attach_bfin_rtc_regs (me, rtc);
 196
 197   /* Initialize the RTC.  */
 198 }
 199
 200 const struct hw_descriptor dv_bfin_rtc_descriptor[] =
 201 {
 202   {"bfin_rtc", bfin_rtc_finish,},
 203   {NULL, NULL},
 204 };