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
|
/*
* (C) Copyright 2009
* Marvell Semiconductor <www.marvell.com>
* Written-by: Prafulla Wadaskar <prafulla@marvell.com>
*
* Derived from drivers/spi/mpc8xxx_spi.c
*
* See file CREDITS for list of people who contributed to this
* project.
*
* 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 2 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, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
* MA 02110-1301 USA
*/
#include <common.h>
#include <malloc.h>
#include <spi.h>
#include <asm/io.h>
#include <asm/arch/kirkwood.h>
#include <asm/arch/spi.h>
#include <asm/arch/mpp.h>
static struct kwspi_registers *spireg = (struct kwspi_registers *)KW_SPI_BASE;
struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
unsigned int max_hz, unsigned int mode)
{
struct spi_slave *slave;
u32 data;
u32 kwspi_mpp_config[] = {
MPP0_GPIO,
MPP7_SPI_SCn,
0
};
if (!spi_cs_is_valid(bus, cs))
return NULL;
slave = malloc(sizeof(struct spi_slave));
if (!slave)
return NULL;
slave->bus = bus;
slave->cs = cs;
writel(~KWSPI_CSN_ACT | KWSPI_SMEMRDY, &spireg->ctrl);
/* calculate spi clock prescaller using max_hz */
data = ((CONFIG_SYS_TCLK / 2) / max_hz) & KWSPI_CLKPRESCL_MASK;
data |= 0x10;
/* program spi clock prescaller using max_hz */
writel(KWSPI_ADRLEN_3BYTE | data, &spireg->cfg);
debug("data = 0x%08x \n", data);
writel(KWSPI_SMEMRDIRQ, &spireg->irq_cause);
writel(KWSPI_IRQMASK, spireg->irq_mask);
/* program mpp registers to select SPI_CSn */
if (cs) {
kwspi_mpp_config[0] = MPP0_GPIO;
kwspi_mpp_config[1] = MPP7_SPI_SCn;
} else {
kwspi_mpp_config[0] = MPP0_SPI_SCn;
kwspi_mpp_config[1] = MPP7_GPO;
}
kirkwood_mpp_conf(kwspi_mpp_config);
return slave;
}
void spi_free_slave(struct spi_slave *slave)
{
free(slave);
}
int spi_claim_bus(struct spi_slave *slave)
{
return 0;
}
void spi_release_bus(struct spi_slave *slave)
{
}
#ifndef CONFIG_SPI_CS_IS_VALID
/*
* you can define this function board specific
* define above CONFIG in board specific config file and
* provide the function in board specific src file
*/
int spi_cs_is_valid(unsigned int bus, unsigned int cs)
{
return (bus == 0 && (cs == 0 || cs == 1));
}
#endif
void spi_cs_activate(struct spi_slave *slave)
{
writel(readl(&spireg->ctrl) | KWSPI_IRQUNMASK, &spireg->ctrl);
}
void spi_cs_deactivate(struct spi_slave *slave)
{
writel(readl(&spireg->ctrl) & KWSPI_IRQMASK, &spireg->ctrl);
}
int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout,
void *din, unsigned long flags)
{
unsigned int tmpdout, tmpdin;
int tm, isread = 0;
debug("spi_xfer: slave %u:%u dout %08X din %08X bitlen %u\n",
slave->bus, slave->cs, dout, din, bitlen);
if (flags & SPI_XFER_BEGIN)
spi_cs_activate(slave);
/*
* handle data in 8-bit chunks
* TBD: 2byte xfer mode to be enabled
*/
writel(((readl(&spireg->cfg) & ~KWSPI_XFERLEN_MASK) |
KWSPI_XFERLEN_1BYTE), &spireg->cfg);
while (bitlen > 4) {
debug("loopstart bitlen %d\n", bitlen);
tmpdout = 0;
/* Shift data so it's msb-justified */
if (dout)
tmpdout = *(u32 *) dout & 0x0ff;
writel(~KWSPI_SMEMRDIRQ, &spireg->irq_cause);
writel(tmpdout, &spireg->dout); /* Write the data out */
debug("*** spi_xfer: ... %08x written, bitlen %d\n",
tmpdout, bitlen);
/*
* Wait for SPI transmit to get out
* or time out (1 second = 1000 ms)
* The NE event must be read and cleared first
*/
for (tm = 0, isread = 0; tm < KWSPI_TIMEOUT; ++tm) {
if (readl(&spireg->irq_cause) & KWSPI_SMEMRDIRQ) {
isread = 1;
tmpdin = readl(&spireg->din);
debug
("spi_xfer: din %08x..%08x read\n",
din, tmpdin);
if (din) {
*((u8 *) din) = (u8) tmpdin;
din += 1;
}
if (dout)
dout += 1;
bitlen -= 8;
}
if (isread)
break;
}
if (tm >= KWSPI_TIMEOUT)
printf("*** spi_xfer: Time out during SPI transfer\n");
debug("loopend bitlen %d\n", bitlen);
}
if (flags & SPI_XFER_END)
spi_cs_deactivate(slave);
return 0;
}
|
