1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * SH SPI driver
4 *
5 * Copyright (C) 2011-2012 Renesas Solutions Corp.
6 */
7
8 #include <common.h>
9 #include <console.h>
10 #include <malloc.h>
11 #include <spi.h>
12 #include <asm/io.h>
13 #include "sh_spi.h"
14
sh_spi_write(unsigned long data,unsigned long * reg)15 static void sh_spi_write(unsigned long data, unsigned long *reg)
16 {
17 writel(data, reg);
18 }
19
sh_spi_read(unsigned long * reg)20 static unsigned long sh_spi_read(unsigned long *reg)
21 {
22 return readl(reg);
23 }
24
sh_spi_set_bit(unsigned long val,unsigned long * reg)25 static void sh_spi_set_bit(unsigned long val, unsigned long *reg)
26 {
27 unsigned long tmp;
28
29 tmp = sh_spi_read(reg);
30 tmp |= val;
31 sh_spi_write(tmp, reg);
32 }
33
sh_spi_clear_bit(unsigned long val,unsigned long * reg)34 static void sh_spi_clear_bit(unsigned long val, unsigned long *reg)
35 {
36 unsigned long tmp;
37
38 tmp = sh_spi_read(reg);
39 tmp &= ~val;
40 sh_spi_write(tmp, reg);
41 }
42
clear_fifo(struct sh_spi * ss)43 static void clear_fifo(struct sh_spi *ss)
44 {
45 sh_spi_set_bit(SH_SPI_RSTF, &ss->regs->cr2);
46 sh_spi_clear_bit(SH_SPI_RSTF, &ss->regs->cr2);
47 }
48
recvbuf_wait(struct sh_spi * ss)49 static int recvbuf_wait(struct sh_spi *ss)
50 {
51 while (sh_spi_read(&ss->regs->cr1) & SH_SPI_RBE) {
52 if (ctrlc())
53 return 1;
54 udelay(10);
55 }
56 return 0;
57 }
58
write_fifo_empty_wait(struct sh_spi * ss)59 static int write_fifo_empty_wait(struct sh_spi *ss)
60 {
61 while (!(sh_spi_read(&ss->regs->cr1) & SH_SPI_TBE)) {
62 if (ctrlc())
63 return 1;
64 udelay(10);
65 }
66 return 0;
67 }
68
sh_spi_set_cs(struct sh_spi * ss,unsigned int cs)69 static void sh_spi_set_cs(struct sh_spi *ss, unsigned int cs)
70 {
71 unsigned long val = 0;
72
73 if (cs & 0x01)
74 val |= SH_SPI_SSS0;
75 if (cs & 0x02)
76 val |= SH_SPI_SSS1;
77
78 sh_spi_clear_bit(SH_SPI_SSS0 | SH_SPI_SSS1, &ss->regs->cr4);
79 sh_spi_set_bit(val, &ss->regs->cr4);
80 }
81
spi_setup_slave(unsigned int bus,unsigned int cs,unsigned int max_hz,unsigned int mode)82 struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
83 unsigned int max_hz, unsigned int mode)
84 {
85 struct sh_spi *ss;
86
87 if (!spi_cs_is_valid(bus, cs))
88 return NULL;
89
90 ss = spi_alloc_slave(struct sh_spi, bus, cs);
91 if (!ss)
92 return NULL;
93
94 ss->regs = (struct sh_spi_regs *)CONFIG_SH_SPI_BASE;
95
96 /* SPI sycle stop */
97 sh_spi_write(0xfe, &ss->regs->cr1);
98 /* CR1 init */
99 sh_spi_write(0x00, &ss->regs->cr1);
100 /* CR3 init */
101 sh_spi_write(0x00, &ss->regs->cr3);
102 sh_spi_set_cs(ss, cs);
103
104 clear_fifo(ss);
105
106 /* 1/8 clock */
107 sh_spi_write(sh_spi_read(&ss->regs->cr2) | 0x07, &ss->regs->cr2);
108 udelay(10);
109
110 return &ss->slave;
111 }
112
spi_free_slave(struct spi_slave * slave)113 void spi_free_slave(struct spi_slave *slave)
114 {
115 struct sh_spi *spi = to_sh_spi(slave);
116
117 free(spi);
118 }
119
spi_claim_bus(struct spi_slave * slave)120 int spi_claim_bus(struct spi_slave *slave)
121 {
122 return 0;
123 }
124
spi_release_bus(struct spi_slave * slave)125 void spi_release_bus(struct spi_slave *slave)
126 {
127 struct sh_spi *ss = to_sh_spi(slave);
128
129 sh_spi_write(sh_spi_read(&ss->regs->cr1) &
130 ~(SH_SPI_SSA | SH_SPI_SSDB | SH_SPI_SSD), &ss->regs->cr1);
131 }
132
sh_spi_send(struct sh_spi * ss,const unsigned char * tx_data,unsigned int len,unsigned long flags)133 static int sh_spi_send(struct sh_spi *ss, const unsigned char *tx_data,
134 unsigned int len, unsigned long flags)
135 {
136 int i, cur_len, ret = 0;
137 int remain = (int)len;
138
139 if (len >= SH_SPI_FIFO_SIZE)
140 sh_spi_set_bit(SH_SPI_SSA, &ss->regs->cr1);
141
142 while (remain > 0) {
143 cur_len = (remain < SH_SPI_FIFO_SIZE) ?
144 remain : SH_SPI_FIFO_SIZE;
145 for (i = 0; i < cur_len &&
146 !(sh_spi_read(&ss->regs->cr4) & SH_SPI_WPABRT) &&
147 !(sh_spi_read(&ss->regs->cr1) & SH_SPI_TBF);
148 i++)
149 sh_spi_write(tx_data[i], &ss->regs->tbr_rbr);
150
151 cur_len = i;
152
153 if (sh_spi_read(&ss->regs->cr4) & SH_SPI_WPABRT) {
154 /* Abort the transaction */
155 flags |= SPI_XFER_END;
156 sh_spi_set_bit(SH_SPI_WPABRT, &ss->regs->cr4);
157 ret = 1;
158 break;
159 }
160
161 remain -= cur_len;
162 tx_data += cur_len;
163
164 if (remain > 0)
165 write_fifo_empty_wait(ss);
166 }
167
168 if (flags & SPI_XFER_END) {
169 sh_spi_clear_bit(SH_SPI_SSD | SH_SPI_SSDB, &ss->regs->cr1);
170 sh_spi_set_bit(SH_SPI_SSA, &ss->regs->cr1);
171 udelay(100);
172 write_fifo_empty_wait(ss);
173 }
174
175 return ret;
176 }
177
sh_spi_receive(struct sh_spi * ss,unsigned char * rx_data,unsigned int len,unsigned long flags)178 static int sh_spi_receive(struct sh_spi *ss, unsigned char *rx_data,
179 unsigned int len, unsigned long flags)
180 {
181 int i;
182
183 if (len > SH_SPI_MAX_BYTE)
184 sh_spi_write(SH_SPI_MAX_BYTE, &ss->regs->cr3);
185 else
186 sh_spi_write(len, &ss->regs->cr3);
187
188 sh_spi_clear_bit(SH_SPI_SSD | SH_SPI_SSDB, &ss->regs->cr1);
189 sh_spi_set_bit(SH_SPI_SSA, &ss->regs->cr1);
190
191 for (i = 0; i < len; i++) {
192 if (recvbuf_wait(ss))
193 return 0;
194
195 rx_data[i] = (unsigned char)sh_spi_read(&ss->regs->tbr_rbr);
196 }
197 sh_spi_write(0, &ss->regs->cr3);
198
199 return 0;
200 }
201
spi_xfer(struct spi_slave * slave,unsigned int bitlen,const void * dout,void * din,unsigned long flags)202 int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout,
203 void *din, unsigned long flags)
204 {
205 struct sh_spi *ss = to_sh_spi(slave);
206 const unsigned char *tx_data = dout;
207 unsigned char *rx_data = din;
208 unsigned int len = bitlen / 8;
209 int ret = 0;
210
211 if (flags & SPI_XFER_BEGIN)
212 sh_spi_write(sh_spi_read(&ss->regs->cr1) & ~SH_SPI_SSA,
213 &ss->regs->cr1);
214
215 if (tx_data)
216 ret = sh_spi_send(ss, tx_data, len, flags);
217
218 if (ret == 0 && rx_data)
219 ret = sh_spi_receive(ss, rx_data, len, flags);
220
221 if (flags & SPI_XFER_END) {
222 sh_spi_set_bit(SH_SPI_SSD, &ss->regs->cr1);
223 udelay(100);
224
225 sh_spi_clear_bit(SH_SPI_SSA | SH_SPI_SSDB | SH_SPI_SSD,
226 &ss->regs->cr1);
227 clear_fifo(ss);
228 }
229
230 return ret;
231 }
232
spi_cs_is_valid(unsigned int bus,unsigned int cs)233 int spi_cs_is_valid(unsigned int bus, unsigned int cs)
234 {
235 if (!bus && cs < SH_SPI_NUM_CS)
236 return 1;
237 else
238 return 0;
239 }
240
spi_cs_activate(struct spi_slave * slave)241 void spi_cs_activate(struct spi_slave *slave)
242 {
243
244 }
245
spi_cs_deactivate(struct spi_slave * slave)246 void spi_cs_deactivate(struct spi_slave *slave)
247 {
248
249 }
250