xref: /openbmc/u-boot/drivers/spi/sh_qspi.c (revision 7da765125165c172078489336117f95de2904322)
1 /*
2  * SH QSPI (Quad SPI) driver
3  *
4  * Copyright (C) 2013 Renesas Electronics Corporation
5  * Copyright (C) 2013 Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
6  *
7  * SPDX-License-Identifier:	GPL-2.0
8  */
9 
10 #include <common.h>
11 #include <malloc.h>
12 #include <spi.h>
13 #include <asm/io.h>
14 
15 /* SH QSPI register bit masks <REG>_<BIT> */
16 #define SPCR_MSTR	0x08
17 #define SPCR_SPE	0x40
18 #define SPSR_SPRFF	0x80
19 #define SPSR_SPTEF	0x20
20 #define SPPCR_IO3FV	0x04
21 #define SPPCR_IO2FV	0x02
22 #define SPPCR_IO1FV	0x01
23 #define SPBDCR_RXBC0	(1 << 0)
24 #define SPCMD_SCKDEN	(1 << 15)
25 #define SPCMD_SLNDEN	(1 << 14)
26 #define SPCMD_SPNDEN	(1 << 13)
27 #define SPCMD_SSLKP	(1 << 7)
28 #define SPCMD_BRDV0	(1 << 2)
29 #define SPCMD_INIT1	SPCMD_SCKDEN | SPCMD_SLNDEN | \
30 			SPCMD_SPNDEN | SPCMD_SSLKP | \
31 			SPCMD_BRDV0
32 #define SPCMD_INIT2	SPCMD_SPNDEN | SPCMD_SSLKP | \
33 			SPCMD_BRDV0
34 #define SPBFCR_TXRST	(1 << 7)
35 #define SPBFCR_RXRST	(1 << 6)
36 
37 /* SH QSPI register set */
38 struct sh_qspi_regs {
39 	unsigned char spcr;
40 	unsigned char sslp;
41 	unsigned char sppcr;
42 	unsigned char spsr;
43 	unsigned long spdr;
44 	unsigned char spscr;
45 	unsigned char spssr;
46 	unsigned char spbr;
47 	unsigned char spdcr;
48 	unsigned char spckd;
49 	unsigned char sslnd;
50 	unsigned char spnd;
51 	unsigned char dummy0;
52 	unsigned short spcmd0;
53 	unsigned short spcmd1;
54 	unsigned short spcmd2;
55 	unsigned short spcmd3;
56 	unsigned char spbfcr;
57 	unsigned char dummy1;
58 	unsigned short spbdcr;
59 	unsigned long spbmul0;
60 	unsigned long spbmul1;
61 	unsigned long spbmul2;
62 	unsigned long spbmul3;
63 };
64 
65 struct sh_qspi_slave {
66 	struct spi_slave	slave;
67 	struct sh_qspi_regs	*regs;
68 };
69 
70 static inline struct sh_qspi_slave *to_sh_qspi(struct spi_slave *slave)
71 {
72 	return container_of(slave, struct sh_qspi_slave, slave);
73 }
74 
75 static void sh_qspi_init(struct sh_qspi_slave *ss)
76 {
77 	/* QSPI initialize */
78 	/* Set master mode only */
79 	writeb(SPCR_MSTR, &ss->regs->spcr);
80 
81 	/* Set SSL signal level */
82 	writeb(0x00, &ss->regs->sslp);
83 
84 	/* Set MOSI signal value when transfer is in idle state */
85 	writeb(SPPCR_IO3FV|SPPCR_IO2FV, &ss->regs->sppcr);
86 
87 	/* Set bit rate. See 58.3.8 Quad Serial Peripheral Interface */
88 	writeb(0x01, &ss->regs->spbr);
89 
90 	/* Disable Dummy Data Transmission */
91 	writeb(0x00, &ss->regs->spdcr);
92 
93 	/* Set clock delay value */
94 	writeb(0x00, &ss->regs->spckd);
95 
96 	/* Set SSL negation delay value */
97 	writeb(0x00, &ss->regs->sslnd);
98 
99 	/* Set next-access delay value */
100 	writeb(0x00, &ss->regs->spnd);
101 
102 	/* Set equence command */
103 	writew(SPCMD_INIT2, &ss->regs->spcmd0);
104 
105 	/* Reset transfer and receive Buffer */
106 	setbits_8(&ss->regs->spbfcr, SPBFCR_TXRST|SPBFCR_RXRST);
107 
108 	/* Clear transfer and receive Buffer control bit */
109 	clrbits_8(&ss->regs->spbfcr, SPBFCR_TXRST|SPBFCR_RXRST);
110 
111 	/* Set equence control method. Use equence0 only */
112 	writeb(0x00, &ss->regs->spscr);
113 
114 	/* Enable SPI function */
115 	setbits_8(&ss->regs->spcr, SPCR_SPE);
116 }
117 
118 int spi_cs_is_valid(unsigned int bus, unsigned int cs)
119 {
120 	return 1;
121 }
122 
123 void spi_cs_activate(struct spi_slave *slave)
124 {
125 	struct sh_qspi_slave *ss = to_sh_qspi(slave);
126 
127 	/* Set master mode only */
128 	writeb(SPCR_MSTR, &ss->regs->spcr);
129 
130 	/* Set command */
131 	writew(SPCMD_INIT1, &ss->regs->spcmd0);
132 
133 	/* Reset transfer and receive Buffer */
134 	setbits_8(&ss->regs->spbfcr, SPBFCR_TXRST|SPBFCR_RXRST);
135 
136 	/* Clear transfer and receive Buffer control bit */
137 	clrbits_8(&ss->regs->spbfcr, SPBFCR_TXRST|SPBFCR_RXRST);
138 
139 	/* Set equence control method. Use equence0 only */
140 	writeb(0x00, &ss->regs->spscr);
141 
142 	/* Enable SPI function */
143 	setbits_8(&ss->regs->spcr, SPCR_SPE);
144 }
145 
146 void spi_cs_deactivate(struct spi_slave *slave)
147 {
148 	struct sh_qspi_slave *ss = to_sh_qspi(slave);
149 
150 	/* Disable SPI Function */
151 	clrbits_8(&ss->regs->spcr, SPCR_SPE);
152 }
153 
154 void spi_init(void)
155 {
156 	/* nothing to do */
157 }
158 
159 struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
160 		unsigned int max_hz, unsigned int mode)
161 {
162 	struct sh_qspi_slave *ss;
163 
164 	if (!spi_cs_is_valid(bus, cs))
165 		return NULL;
166 
167 	ss = spi_alloc_slave(struct sh_qspi_slave, bus, cs);
168 	if (!ss) {
169 		printf("SPI_error: Fail to allocate sh_qspi_slave\n");
170 		return NULL;
171 	}
172 
173 	ss->regs = (struct sh_qspi_regs *)CONFIG_SH_QSPI_BASE;
174 
175 	/* Init SH QSPI */
176 	sh_qspi_init(ss);
177 
178 	return &ss->slave;
179 }
180 
181 void spi_free_slave(struct spi_slave *slave)
182 {
183 	struct sh_qspi_slave *spi = to_sh_qspi(slave);
184 
185 	free(spi);
186 }
187 
188 int spi_claim_bus(struct spi_slave *slave)
189 {
190 	return 0;
191 }
192 
193 void spi_release_bus(struct spi_slave *slave)
194 {
195 }
196 
197 int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout,
198 	     void *din, unsigned long flags)
199 {
200 	struct sh_qspi_slave *ss = to_sh_qspi(slave);
201 	unsigned long nbyte;
202 	int ret = 0;
203 	unsigned char dtdata = 0, drdata;
204 	unsigned char *tdata = &dtdata, *rdata = &drdata;
205 	unsigned long *spbmul0 = &ss->regs->spbmul0;
206 
207 	if (dout == NULL && din == NULL) {
208 		if (flags & SPI_XFER_END)
209 			spi_cs_deactivate(slave);
210 		return 0;
211 	}
212 
213 	if (bitlen % 8) {
214 		printf("%s: bitlen is not 8bit alined %d", __func__, bitlen);
215 		return 1;
216 	}
217 
218 	nbyte = bitlen / 8;
219 
220 	if (flags & SPI_XFER_BEGIN) {
221 		spi_cs_activate(slave);
222 
223 		/* Set 1048576 byte */
224 		writel(0x100000, spbmul0);
225 	}
226 
227 	if (flags & SPI_XFER_END)
228 		writel(nbyte, spbmul0);
229 
230 	if (dout != NULL)
231 		tdata = (unsigned char *)dout;
232 
233 	if (din != NULL)
234 		rdata = din;
235 
236 	while (nbyte > 0) {
237 		while (!(readb(&ss->regs->spsr) & SPSR_SPTEF)) {
238 			if (ctrlc()) {
239 				puts("abort\n");
240 				return 1;
241 			}
242 			udelay(10);
243 		}
244 
245 		writeb(*tdata, (unsigned char *)(&ss->regs->spdr));
246 
247 		while ((readw(&ss->regs->spbdcr) != SPBDCR_RXBC0)) {
248 			if (ctrlc()) {
249 				puts("abort\n");
250 				return 1;
251 			}
252 			udelay(1);
253 		}
254 
255 		while (!(readb(&ss->regs->spsr) & SPSR_SPRFF)) {
256 			if (ctrlc()) {
257 				puts("abort\n");
258 				return 1;
259 			}
260 			udelay(10);
261 		}
262 
263 		*rdata = readb((unsigned char *)(&ss->regs->spdr));
264 
265 		if (dout != NULL)
266 			tdata++;
267 		if (din != NULL)
268 			rdata++;
269 
270 		nbyte--;
271 	}
272 
273 	if (flags & SPI_XFER_END)
274 		spi_cs_deactivate(slave);
275 
276 	return ret;
277 }
278