sim/bfin/dv-bfin_jtag.c

   1 /* Blackfin JTAG model.
   2
   3    Copyright (C) 2010-2013 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 {
  44   "DSPID", NULL, "DBGSTAT",
  45 };
  46 #define mmr_name(off) (mmr_names[(off) / 4] ? : "<INV>")
  47
  48 static unsigned
  49 bfin_jtag_io_write_buffer (struct hw *me, const void *source, int space,
  50                            address_word addr, unsigned nr_bytes)
  51 {
  52   struct bfin_jtag *jtag = hw_data (me);
  53   bu32 mmr_off;
  54   bu32 value;
  55   bu32 *valuep;
  56
  57   value = dv_load_4 (source);
  58   mmr_off = addr - jtag->base;
  59   valuep = (void *)((unsigned long)jtag + mmr_base() + mmr_off);
  60
  61   HW_TRACE_WRITE ();
  62
  63   switch (mmr_off)
  64     {
  65     case mmr_offset(dbgstat):
  66       dv_w1c_4 (valuep, value, 0xc);
  67       break;
  68     case mmr_offset(dspid):
  69       /* Discard writes to these.  */
  70       break;
  71     default:
  72       dv_bfin_mmr_invalid (me, addr, nr_bytes, true);
  73       break;
  74     }
  75
  76   return nr_bytes;
  77 }
  78
  79 static unsigned
  80 bfin_jtag_io_read_buffer (struct hw *me, void *dest, int space,
  81                           address_word addr, unsigned nr_bytes)
  82 {
  83   struct bfin_jtag *jtag = hw_data (me);
  84   bu32 mmr_off;
  85   bu32 value;
  86   bu32 *valuep;
  87
  88   mmr_off = addr - jtag->base;
  89   valuep = (void *)((unsigned long)jtag + mmr_base() + mmr_off);
  90
  91   HW_TRACE_READ ();
  92
  93   switch (mmr_off)
  94     {
  95     case mmr_offset(dbgstat):
  96     case mmr_offset(dspid):
  97       value = *valuep;
  98       break;
  99     default:
 100       while (1) /* Core MMRs -> exception -> doesn't return.  */
 101         dv_bfin_mmr_invalid (me, addr, nr_bytes, false);
 102       break;
 103     }
 104
 105   dv_store_4 (dest, value);
 106
 107   return nr_bytes;
 108 }
 109
 110 static void
 111 attach_bfin_jtag_regs (struct hw *me, struct bfin_jtag *jtag)
 112 {
 113   address_word attach_address;
 114   int attach_space;
 115   unsigned attach_size;
 116   reg_property_spec reg;
 117
 118   if (hw_find_property (me, "reg") == NULL)
 119     hw_abort (me, "Missing \"reg\" property");
 120
 121   if (!hw_find_reg_array_property (me, "reg", 0, &reg))
 122     hw_abort (me, "\"reg\" property must contain three addr/size entries");
 123
 124   hw_unit_address_to_attach_address (hw_parent (me),
 125                                      &reg.address,
 126                                      &attach_space, &attach_address, me);
 127   hw_unit_size_to_attach_size (hw_parent (me), &reg.size, &attach_size, me);
 128
 129   if (attach_size != BFIN_COREMMR_JTAG_SIZE)
 130     hw_abort (me, "\"reg\" size must be %#x", BFIN_COREMMR_JTAG_SIZE);
 131
 132   hw_attach_address (hw_parent (me),
 133                      0, attach_space, attach_address, attach_size, me);
 134
 135   jtag->base = attach_address;
 136 }
 137
 138 static void
 139 bfin_jtag_finish (struct hw *me)
 140 {
 141   struct bfin_jtag *jtag;
 142
 143   jtag = HW_ZALLOC (me, struct bfin_jtag);
 144
 145   set_hw_data (me, jtag);
 146   set_hw_io_read_buffer (me, bfin_jtag_io_read_buffer);
 147   set_hw_io_write_buffer (me, bfin_jtag_io_write_buffer);
 148
 149   attach_bfin_jtag_regs (me, jtag);
 150
 151   /* Initialize the JTAG state.  */
 152   jtag->dspid = bfin_model_get_dspid (hw_system (me));
 153 }
 154
 155 const struct hw_descriptor dv_bfin_jtag_descriptor[] =
 156 {
 157   {"bfin_jtag", bfin_jtag_finish,},
 158   {NULL, NULL},
 159 };