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
|
/*
* This file is part of the flashrom project.
*
* Copyright (C) 2009, 2010 Carl-Daniel Hailfinger
*
* 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; version 2 of the License.
*
* 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.
*/
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <ctype.h>
#include "flash.h"
#include "programmer.h"
#include "spi.h"
/* Note that CS# is active low, so val=0 means the chip is active. */
static void bitbang_spi_set_cs(const struct bitbang_spi_master * const master, int val)
{
master->set_cs(val);
}
static void bitbang_spi_set_sck(const struct bitbang_spi_master * const master, int val)
{
master->set_sck(val);
}
static void bitbang_spi_request_bus(const struct bitbang_spi_master * const master)
{
if (master->request_bus)
master->request_bus();
}
static void bitbang_spi_release_bus(const struct bitbang_spi_master * const master)
{
if (master->release_bus)
master->release_bus();
}
static void bitbang_spi_set_sck_set_mosi(const struct bitbang_spi_master * const master, int sck, int mosi)
{
if (master->set_sck_set_mosi) {
master->set_sck_set_mosi(sck, mosi);
return;
}
master->set_sck(sck);
master->set_mosi(mosi);
}
static int bitbang_spi_set_sck_get_miso(const struct bitbang_spi_master * const master, int sck)
{
if (master->set_sck_get_miso)
return master->set_sck_get_miso(sck);
master->set_sck(sck);
return master->get_miso();
}
static uint8_t bitbang_spi_read_byte(const struct bitbang_spi_master *master)
{
uint8_t ret = 0;
int i;
for (i = 7; i >= 0; i--) {
if (i == 0)
bitbang_spi_set_sck_set_mosi(master, 0, 0);
else
bitbang_spi_set_sck(master, 0);
programmer_delay(master->half_period);
ret <<= 1;
ret |= bitbang_spi_set_sck_get_miso(master, 1);
programmer_delay(master->half_period);
}
return ret;
}
static void bitbang_spi_write_byte(const struct bitbang_spi_master *master, uint8_t val)
{
int i;
for (i = 7; i >= 0; i--) {
bitbang_spi_set_sck_set_mosi(master, 0, (val >> i) & 1);
programmer_delay(master->half_period);
bitbang_spi_set_sck(master, 1);
programmer_delay(master->half_period);
}
}
struct bitbang_spi_master_data {
const struct bitbang_spi_master *mst;
};
static int bitbang_spi_send_command(const struct flashctx *flash,
unsigned int writecnt, unsigned int readcnt,
const unsigned char *writearr,
unsigned char *readarr)
{
unsigned int i;
const struct bitbang_spi_master_data *data = flash->mst->spi.data;
const struct bitbang_spi_master *master = data->mst;
/* FIXME: Run bitbang_spi_request_bus here or in programmer init?
* Requesting and releasing the SPI bus is handled in here to allow the
* programmer to use its own SPI engine for native accesses.
*/
bitbang_spi_request_bus(master);
bitbang_spi_set_cs(master, 0);
for (i = 0; i < writecnt; i++)
bitbang_spi_write_byte(master, writearr[i]);
for (i = 0; i < readcnt; i++)
readarr[i] = bitbang_spi_read_byte(master);
bitbang_spi_set_sck(master, 0);
programmer_delay(master->half_period);
bitbang_spi_set_cs(master, 1);
programmer_delay(master->half_period);
/* FIXME: Run bitbang_spi_release_bus here or in programmer init? */
bitbang_spi_release_bus(master);
return 0;
}
static const struct spi_master spi_master_bitbang = {
.features = SPI_MASTER_4BA,
.max_data_read = MAX_DATA_READ_UNLIMITED,
.max_data_write = MAX_DATA_WRITE_UNLIMITED,
.command = bitbang_spi_send_command,
.multicommand = default_spi_send_multicommand,
.read = default_spi_read,
.write_256 = default_spi_write_256,
.write_aai = default_spi_write_aai,
};
static int bitbang_spi_shutdown(void *data)
{
/* FIXME: Run bitbang_spi_release_bus here or per command? */
free(data);
return 0;
}
int register_spi_bitbang_master(const struct bitbang_spi_master *master)
{
struct spi_master mst = spi_master_bitbang;
/* If someone forgot to initialize a bitbang function, we catch it here. */
if (!master || !master->set_cs ||
!master->set_sck || !master->set_mosi || !master->get_miso ||
(master->request_bus && !master->release_bus) ||
(!master->request_bus && master->release_bus)) {
msg_perr("Incomplete SPI bitbang master setting!\n"
"Please report a bug at flashrom@flashrom.org\n");
return ERROR_FLASHROM_BUG;
}
struct bitbang_spi_master_data *data = calloc(1, sizeof(struct bitbang_spi_master_data));
data->mst = master;
mst.data = data;
register_spi_master(&mst);
register_shutdown(bitbang_spi_shutdown, data);
/* Only mess with the bus if we're sure nobody else uses it. */
bitbang_spi_request_bus(master);
bitbang_spi_set_cs(master, 1);
bitbang_spi_set_sck_set_mosi(master, 0, 0);
/* FIXME: Release SPI bus here and request it again for each command or
* don't release it now and only release it on programmer shutdown?
*/
bitbang_spi_release_bus(master);
return 0;
}
|
