xref: /openbmc/u-boot/drivers/spi/sh_qspi.c (revision d7cbcc76)
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/arch/rmobile.h>
14 #include <asm/io.h>
15 
16 /* SH QSPI register bit masks <REG>_<BIT> */
17 #define SPCR_MSTR	0x08
18 #define SPCR_SPE	0x40
19 #define SPSR_SPRFF	0x80
20 #define SPSR_SPTEF	0x20
21 #define SPPCR_IO3FV	0x04
22 #define SPPCR_IO2FV	0x02
23 #define SPPCR_IO1FV	0x01
24 #define SPBDCR_RXBC0	(1 << 0)
25 #define SPCMD_SCKDEN	(1 << 15)
26 #define SPCMD_SLNDEN	(1 << 14)
27 #define SPCMD_SPNDEN	(1 << 13)
28 #define SPCMD_SSLKP	(1 << 7)
29 #define SPCMD_BRDV0	(1 << 2)
30 #define SPCMD_INIT1	SPCMD_SCKDEN | SPCMD_SLNDEN | \
31 			SPCMD_SPNDEN | SPCMD_SSLKP | \
32 			SPCMD_BRDV0
33 #define SPCMD_INIT2	SPCMD_SPNDEN | SPCMD_SSLKP | \
34 			SPCMD_BRDV0
35 #define SPBFCR_TXRST	(1 << 7)
36 #define SPBFCR_RXRST	(1 << 6)
37 
38 /* SH QSPI register set */
39 struct sh_qspi_regs {
40 	unsigned char spcr;
41 	unsigned char sslp;
42 	unsigned char sppcr;
43 	unsigned char spsr;
44 	unsigned long spdr;
45 	unsigned char spscr;
46 	unsigned char spssr;
47 	unsigned char spbr;
48 	unsigned char spdcr;
49 	unsigned char spckd;
50 	unsigned char sslnd;
51 	unsigned char spnd;
52 	unsigned char dummy0;
53 	unsigned short spcmd0;
54 	unsigned short spcmd1;
55 	unsigned short spcmd2;
56 	unsigned short spcmd3;
57 	unsigned char spbfcr;
58 	unsigned char dummy1;
59 	unsigned short spbdcr;
60 	unsigned long spbmul0;
61 	unsigned long spbmul1;
62 	unsigned long spbmul2;
63 	unsigned long spbmul3;
64 };
65 
66 struct sh_qspi_slave {
67 	struct spi_slave	slave;
68 	struct sh_qspi_regs	*regs;
69 };
70 
71 static inline struct sh_qspi_slave *to_sh_qspi(struct spi_slave *slave)
72 {
73 	return container_of(slave, struct sh_qspi_slave, slave);
74 }
75 
76 static void sh_qspi_init(struct sh_qspi_slave *ss)
77 {
78 	/* QSPI initialize */
79 	/* Set master mode only */
80 	writeb(SPCR_MSTR, &ss->regs->spcr);
81 
82 	/* Set SSL signal level */
83 	writeb(0x00, &ss->regs->sslp);
84 
85 	/* Set MOSI signal value when transfer is in idle state */
86 	writeb(SPPCR_IO3FV|SPPCR_IO2FV, &ss->regs->sppcr);
87 
88 	/* Set bit rate. See 58.3.8 Quad Serial Peripheral Interface */
89 	writeb(0x01, &ss->regs->spbr);
90 
91 	/* Disable Dummy Data Transmission */
92 	writeb(0x00, &ss->regs->spdcr);
93 
94 	/* Set clock delay value */
95 	writeb(0x00, &ss->regs->spckd);
96 
97 	/* Set SSL negation delay value */
98 	writeb(0x00, &ss->regs->sslnd);
99 
100 	/* Set next-access delay value */
101 	writeb(0x00, &ss->regs->spnd);
102 
103 	/* Set equence command */
104 	writew(SPCMD_INIT2, &ss->regs->spcmd0);
105 
106 	/* Reset transfer and receive Buffer */
107 	setbits_8(&ss->regs->spbfcr, SPBFCR_TXRST|SPBFCR_RXRST);
108 
109 	/* Clear transfer and receive Buffer control bit */
110 	clrbits_8(&ss->regs->spbfcr, SPBFCR_TXRST|SPBFCR_RXRST);
111 
112 	/* Set equence control method. Use equence0 only */
113 	writeb(0x00, &ss->regs->spscr);
114 
115 	/* Enable SPI function */
116 	setbits_8(&ss->regs->spcr, SPCR_SPE);
117 }
118 
119 int spi_cs_is_valid(unsigned int bus, unsigned int cs)
120 {
121 	return 1;
122 }
123 
124 void spi_cs_activate(struct spi_slave *slave)
125 {
126 	struct sh_qspi_slave *ss = to_sh_qspi(slave);
127 
128 	/* Set master mode only */
129 	writeb(SPCR_MSTR, &ss->regs->spcr);
130 
131 	/* Set command */
132 	writew(SPCMD_INIT1, &ss->regs->spcmd0);
133 
134 	/* Reset transfer and receive Buffer */
135 	setbits_8(&ss->regs->spbfcr, SPBFCR_TXRST|SPBFCR_RXRST);
136 
137 	/* Clear transfer and receive Buffer control bit */
138 	clrbits_8(&ss->regs->spbfcr, SPBFCR_TXRST|SPBFCR_RXRST);
139 
140 	/* Set equence control method. Use equence0 only */
141 	writeb(0x00, &ss->regs->spscr);
142 
143 	/* Enable SPI function */
144 	setbits_8(&ss->regs->spcr, SPCR_SPE);
145 }
146 
147 void spi_cs_deactivate(struct spi_slave *slave)
148 {
149 	struct sh_qspi_slave *ss = to_sh_qspi(slave);
150 
151 	/* Disable SPI Function */
152 	clrbits_8(&ss->regs->spcr, SPCR_SPE);
153 }
154 
155 void spi_init(void)
156 {
157 	/* nothing to do */
158 }
159 
160 struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
161 		unsigned int max_hz, unsigned int mode)
162 {
163 	struct sh_qspi_slave *ss;
164 
165 	if (!spi_cs_is_valid(bus, cs))
166 		return NULL;
167 
168 	ss = spi_alloc_slave(struct sh_qspi_slave, bus, cs);
169 	if (!ss) {
170 		printf("SPI_error: Fail to allocate sh_qspi_slave\n");
171 		return NULL;
172 	}
173 
174 	ss->regs = (struct sh_qspi_regs *)SH_QSPI_BASE;
175 
176 	/* Init SH QSPI */
177 	sh_qspi_init(ss);
178 
179 	return &ss->slave;
180 }
181 
182 void spi_free_slave(struct spi_slave *slave)
183 {
184 	struct sh_qspi_slave *spi = to_sh_qspi(slave);
185 
186 	free(spi);
187 }
188 
189 int spi_claim_bus(struct spi_slave *slave)
190 {
191 	return 0;
192 }
193 
194 void spi_release_bus(struct spi_slave *slave)
195 {
196 }
197 
198 int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout,
199 	     void *din, unsigned long flags)
200 {
201 	struct sh_qspi_slave *ss = to_sh_qspi(slave);
202 	unsigned long nbyte;
203 	int ret = 0;
204 	unsigned char dtdata = 0, drdata;
205 	unsigned char *tdata = &dtdata, *rdata = &drdata;
206 	unsigned long *spbmul0 = &ss->regs->spbmul0;
207 
208 	if (dout == NULL && din == NULL) {
209 		if (flags & SPI_XFER_END)
210 			spi_cs_deactivate(slave);
211 		return 0;
212 	}
213 
214 	if (bitlen % 8) {
215 		printf("%s: bitlen is not 8bit alined %d", __func__, bitlen);
216 		return 1;
217 	}
218 
219 	nbyte = bitlen / 8;
220 
221 	if (flags & SPI_XFER_BEGIN) {
222 		spi_cs_activate(slave);
223 
224 		/* Set 1048576 byte */
225 		writel(0x100000, spbmul0);
226 	}
227 
228 	if (flags & SPI_XFER_END)
229 		writel(nbyte, spbmul0);
230 
231 	if (dout != NULL)
232 		tdata = (unsigned char *)dout;
233 
234 	if (din != NULL)
235 		rdata = din;
236 
237 	while (nbyte > 0) {
238 		while (!(readb(&ss->regs->spsr) & SPSR_SPTEF)) {
239 			if (ctrlc()) {
240 				puts("abort\n");
241 				return 1;
242 			}
243 			udelay(10);
244 		}
245 
246 		writeb(*tdata, (unsigned char *)(&ss->regs->spdr));
247 
248 		while ((readw(&ss->regs->spbdcr) != SPBDCR_RXBC0)) {
249 			if (ctrlc()) {
250 				puts("abort\n");
251 				return 1;
252 			}
253 			udelay(1);
254 		}
255 
256 		while (!(readb(&ss->regs->spsr) & SPSR_SPRFF)) {
257 			if (ctrlc()) {
258 				puts("abort\n");
259 				return 1;
260 			}
261 			udelay(10);
262 		}
263 
264 		*rdata = readb((unsigned char *)(&ss->regs->spdr));
265 
266 		if (dout != NULL)
267 			tdata++;
268 		if (din != NULL)
269 			rdata++;
270 
271 		nbyte--;
272 	}
273 
274 	if (flags & SPI_XFER_END)
275 		spi_cs_deactivate(slave);
276 
277 	return ret;
278 }
279