aboutsummaryrefslogtreecommitdiff
path: root/sim/bfin/dv-bfin_twi.c
blob: 4e6783ded5cdd25fc3696c0c0be3efc19625266a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
/* Blackfin Two Wire Interface (TWI) model

   Copyright (C) 2010-2011 Free Software Foundation, Inc.
   Contributed by Analog Devices, Inc.

   This file is part of simulators.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

#include "config.h"

#include "sim-main.h"
#include "devices.h"
#include "dv-bfin_twi.h"

/* XXX: This is merely a stub.  */

struct bfin_twi
{
  /* This top portion matches common dv_bfin struct.  */
  bu32 base;
  struct hw *dma_master;
  bool acked;

  struct hw_event *handler;
  char saved_byte;
  int saved_count;

  bu16 xmt_fifo, rcv_fifo;

  /* Order after here is important -- matches hardware MMR layout.  */
  bu16 BFIN_MMR_16(clkdiv);
  bu16 BFIN_MMR_16(control);
  bu16 BFIN_MMR_16(slave_ctl);
  bu16 BFIN_MMR_16(slave_stat);
  bu16 BFIN_MMR_16(slave_addr);
  bu16 BFIN_MMR_16(master_ctl);
  bu16 BFIN_MMR_16(master_stat);
  bu16 BFIN_MMR_16(master_addr);
  bu16 BFIN_MMR_16(int_stat);
  bu16 BFIN_MMR_16(int_mask);
  bu16 BFIN_MMR_16(fifo_ctl);
  bu16 BFIN_MMR_16(fifo_stat);
  bu32 _pad0[20];
  bu16 BFIN_MMR_16(xmt_data8);
  bu16 BFIN_MMR_16(xmt_data16);
  bu16 BFIN_MMR_16(rcv_data8);
  bu16 BFIN_MMR_16(rcv_data16);
};
#define mmr_base()      offsetof(struct bfin_twi, clkdiv)
#define mmr_offset(mmr) (offsetof(struct bfin_twi, mmr) - mmr_base())
#define mmr_idx(mmr)    (mmr_offset (mmr) / 4)

static const char * const mmr_names[] = {
  "TWI_CLKDIV", "TWI_CONTROL", "TWI_SLAVE_CTL", "TWI_SLAVE_STAT",
  "TWI_SLAVE_ADDR", "TWI_MASTER_CTL", "TWI_MASTER_STAT", "TWI_MASTER_ADDR",
  "TWI_INT_STAT", "TWI_INT_MASK", "TWI_FIFO_CTL", "TWI_FIFO_STAT",
  [mmr_idx (xmt_data8)] = "TWI_XMT_DATA8", "TWI_XMT_DATA16", "TWI_RCV_DATA8",
  "TWI_RCV_DATA16",
};
#define mmr_name(off) (mmr_names[(off) / 4] ? : "<INV>")

static unsigned
bfin_twi_io_write_buffer (struct hw *me, const void *source, int space,
			  address_word addr, unsigned nr_bytes)
{
  struct bfin_twi *twi = hw_data (me);
  bu32 mmr_off;
  bu32 value;
  bu16 *valuep;

  value = dv_load_2 (source);
  mmr_off = addr - twi->base;
  valuep = (void *)((unsigned long)twi + mmr_base() + mmr_off);

  HW_TRACE_WRITE ();

  dv_bfin_mmr_require_16 (me, addr, nr_bytes, true);

  switch (mmr_off)
    {
    case mmr_offset(clkdiv):
    case mmr_offset(control):
    case mmr_offset(slave_ctl):
    case mmr_offset(slave_addr):
    case mmr_offset(master_ctl):
    case mmr_offset(master_addr):
    case mmr_offset(int_mask):
    case mmr_offset(fifo_ctl):
      *valuep = value;
      break;
    case mmr_offset(int_stat):
      dv_w1c_2 (valuep, value, 0);
      break;
    case mmr_offset(master_stat):
      dv_w1c_2 (valuep, value, MPROG | SDASEN | SCLSEN | BUSBUSY);
      break;
    case mmr_offset(slave_stat):
    case mmr_offset(fifo_stat):
    case mmr_offset(rcv_data8):
    case mmr_offset(rcv_data16):
      /* These are all RO.  XXX: Does these throw error ?  */
      break;
    case mmr_offset(xmt_data8):
      value &= 0xff;
    case mmr_offset(xmt_data16):
      twi->xmt_fifo = value;
      break;
    default:
      dv_bfin_mmr_invalid (me, addr, nr_bytes, true);
      break;
    }

  return nr_bytes;
}

static unsigned
bfin_twi_io_read_buffer (struct hw *me, void *dest, int space,
			 address_word addr, unsigned nr_bytes)
{
  struct bfin_twi *twi = hw_data (me);
  bu32 mmr_off;
  bu16 *valuep;

  mmr_off = addr - twi->base;
  valuep = (void *)((unsigned long)twi + mmr_base() + mmr_off);

  HW_TRACE_READ ();

  dv_bfin_mmr_require_16 (me, addr, nr_bytes, false);

  switch (mmr_off)
    {
    case mmr_offset(clkdiv):
    case mmr_offset(control):
    case mmr_offset(slave_ctl):
    case mmr_offset(slave_stat):
    case mmr_offset(slave_addr):
    case mmr_offset(master_ctl):
    case mmr_offset(master_stat):
    case mmr_offset(master_addr):
    case mmr_offset(int_stat):
    case mmr_offset(int_mask):
    case mmr_offset(fifo_ctl):
    case mmr_offset(fifo_stat):
      dv_store_2 (dest, *valuep);
      break;
    case mmr_offset(rcv_data8):
    case mmr_offset(rcv_data16):
      dv_store_2 (dest, twi->rcv_fifo);
      break;
    case mmr_offset(xmt_data8):
    case mmr_offset(xmt_data16):
      /* These always read as 0.  */
      dv_store_2 (dest, 0);
      break;
    default:
      dv_bfin_mmr_invalid (me, addr, nr_bytes, false);
      break;
    }

  return nr_bytes;
}

static const struct hw_port_descriptor bfin_twi_ports[] = {
  { "stat", 0, 0, output_port, },
  { NULL, 0, 0, 0, },
};

static void
attach_bfin_twi_regs (struct hw *me, struct bfin_twi *twi)
{
  address_word attach_address;
  int attach_space;
  unsigned attach_size;
  reg_property_spec reg;

  if (hw_find_property (me, "reg") == NULL)
    hw_abort (me, "Missing \"reg\" property");

  if (!hw_find_reg_array_property (me, "reg", 0, &reg))
    hw_abort (me, "\"reg\" property must contain three addr/size entries");

  hw_unit_address_to_attach_address (hw_parent (me),
				     &reg.address,
				     &attach_space, &attach_address, me);
  hw_unit_size_to_attach_size (hw_parent (me), &reg.size, &attach_size, me);

  if (attach_size != BFIN_MMR_TWI_SIZE)
    hw_abort (me, "\"reg\" size must be %#x", BFIN_MMR_TWI_SIZE);

  hw_attach_address (hw_parent (me),
		     0, attach_space, attach_address, attach_size, me);

  twi->base = attach_address;
}

static void
bfin_twi_finish (struct hw *me)
{
  struct bfin_twi *twi;

  twi = HW_ZALLOC (me, struct bfin_twi);

  set_hw_data (me, twi);
  set_hw_io_read_buffer (me, bfin_twi_io_read_buffer);
  set_hw_io_write_buffer (me, bfin_twi_io_write_buffer);
  set_hw_ports (me, bfin_twi_ports);

  attach_bfin_twi_regs (me, twi);
}

const struct hw_descriptor dv_bfin_twi_descriptor[] = {
  {"bfin_twi", bfin_twi_finish,},
  {NULL, NULL},
};