sim/bfin/dv-bfin_jtag.c

   1 /* Blackfin JTAG model.
   2
   3    Copyright (C) 2010-2011 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 #include "config.h"
  22
  23 #include "sim-main.h"
  24 #include "devices.h"
  25 #include "dv-bfin_jtag.h"
  26
  27 /* XXX: This is mostly a stub.  There are more registers, but they're only
  28         accessible via the JTAG scan chain and not the MMR interface.  */
  29
  30 struct bfin_jtag
  31 {
  32   bu32 base;
  33
  34   /* Order after here is important -- matches hardware MMR layout.  */
  35   bu32 dspid;
  36   bu32 _pad0;
  37   bu32 dbgstat;
  38 };
  39 #define mmr_base()      offsetof(struct bfin_jtag, dspid)
  40 #define mmr_offset(mmr) (offsetof(struct bfin_jtag, mmr) - mmr_base())
  41
  42 static const char * const mmr_names[] = {
  43   "DSPID", NULL, "DBGSTAT",
  44 };
  45 #define mmr_name(off) (mmr_names[(off) / 4] ? : "<INV>")
  46
  47 static unsigned
  48 bfin_jtag_io_write_buffer (struct hw *me, const void *source, int space,
  49                            address_word addr, unsigned nr_bytes)
  50 {
  51   struct bfin_jtag *jtag = hw_data (me);
  52   bu32 mmr_off;
  53   bu32 value;
  54   bu32 *valuep;
  55
  56   value = dv_load_4 (source);
  57   mmr_off = addr - jtag->base;
  58   valuep = (void *)((unsigned long)jtag + mmr_base() + mmr_off);
  59
  60   HW_TRACE_WRITE ();
  61
  62   switch (mmr_off)
  63     {
  64     case mmr_offset(dbgstat):
  65       dv_w1c_4 (valuep, value, ~0xc);
  66       break;
  67     case mmr_offset(dspid):
  68       /* Discard writes to these.  */
  69       break;
  70     default:
  71       dv_bfin_mmr_invalid (me, addr, nr_bytes, true);
  72       break;
  73     }
  74
  75   return nr_bytes;
  76 }
  77
  78 static unsigned
  79 bfin_jtag_io_read_buffer (struct hw *me, void *dest, int space,
  80                           address_word addr, unsigned nr_bytes)
  81 {
  82   struct bfin_jtag *jtag = hw_data (me);
  83   bu32 mmr_off;
  84   bu32 value;
  85   bu32 *valuep;
  86
  87   mmr_off = addr - jtag->base;
  88   valuep = (void *)((unsigned long)jtag + mmr_base() + mmr_off);
  89
  90   HW_TRACE_READ ();
  91
  92   switch (mmr_off)
  93     {
  94     case mmr_offset(dbgstat):
  95     case mmr_offset(dspid):
  96       value = *valuep;
  97       break;
  98     default:
  99       while (1) /* Core MMRs -> exception -> doesn't return.  */
 100         dv_bfin_mmr_invalid (me, addr, nr_bytes, false);
 101       break;
 102     }
 103
 104   dv_store_4 (dest, value);
 105
 106   return nr_bytes;
 107 }
 108
 109 static void
 110 attach_bfin_jtag_regs (struct hw *me, struct bfin_jtag *jtag)
 111 {
 112   address_word attach_address;
 113   int attach_space;
 114   unsigned attach_size;
 115   reg_property_spec reg;
 116
 117   if (hw_find_property (me, "reg") == NULL)
 118     hw_abort (me, "Missing \"reg\" property");
 119
 120   if (!hw_find_reg_array_property (me, "reg", 0, &reg))
 121     hw_abort (me, "\"reg\" property must contain three addr/size entries");
 122
 123   hw_unit_address_to_attach_address (hw_parent (me),
 124                                      &reg.address,
 125                                      &attach_space, &attach_address, me);
 126   hw_unit_size_to_attach_size (hw_parent (me), &reg.size, &attach_size, me);
 127
 128   if (attach_size != BFIN_COREMMR_JTAG_SIZE)
 129     hw_abort (me, "\"reg\" size must be %#x", BFIN_COREMMR_JTAG_SIZE);
 130
 131   hw_attach_address (hw_parent (me),
 132                      0, attach_space, attach_address, attach_size, me);
 133
 134   jtag->base = attach_address;
 135 }
 136
 137 static void
 138 bfin_jtag_finish (struct hw *me)
 139 {
 140   struct bfin_jtag *jtag;
 141
 142   jtag = HW_ZALLOC (me, struct bfin_jtag);
 143
 144   set_hw_data (me, jtag);
 145   set_hw_io_read_buffer (me, bfin_jtag_io_read_buffer);
 146   set_hw_io_write_buffer (me, bfin_jtag_io_write_buffer);
 147
 148   attach_bfin_jtag_regs (me, jtag);
 149
 150   /* Initialize the JTAG state.  */
 151   jtag->dspid = bfin_model_get_dspid (hw_system (me));
 152 }
 153
 154 const struct hw_descriptor dv_bfin_jtag_descriptor[] = {
 155   {"bfin_jtag", bfin_jtag_finish,},
 156   {NULL, NULL},
 157 };