xref: /openbmc/u-boot/drivers/spi/sh_qspi.c (revision c978b524)
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 <console.h>
12 #include <malloc.h>
13 #include <spi.h>
14 #include <asm/arch/rmobile.h>
15 #include <asm/io.h>
16 
17 /* SH QSPI register bit masks <REG>_<BIT> */
18 #define SPCR_MSTR	0x08
19 #define SPCR_SPE	0x40
20 #define SPSR_SPRFF	0x80
21 #define SPSR_SPTEF	0x20
22 #define SPPCR_IO3FV	0x04
23 #define SPPCR_IO2FV	0x02
24 #define SPPCR_IO1FV	0x01
25 #define SPBDCR_RXBC0	BIT(0)
26 #define SPCMD_SCKDEN	BIT(15)
27 #define SPCMD_SLNDEN	BIT(14)
28 #define SPCMD_SPNDEN	BIT(13)
29 #define SPCMD_SSLKP	BIT(7)
30 #define SPCMD_BRDV0	BIT(2)
31 #define SPCMD_INIT1	SPCMD_SCKDEN | SPCMD_SLNDEN | \
32 			SPCMD_SPNDEN | SPCMD_SSLKP | \
33 			SPCMD_BRDV0
34 #define SPCMD_INIT2	SPCMD_SPNDEN | SPCMD_SSLKP | \
35 			SPCMD_BRDV0
36 #define SPBFCR_TXRST	BIT(7)
37 #define SPBFCR_RXRST	BIT(6)
38 
39 /* SH QSPI register set */
40 struct sh_qspi_regs {
41 	unsigned char spcr;
42 	unsigned char sslp;
43 	unsigned char sppcr;
44 	unsigned char spsr;
45 	unsigned long spdr;
46 	unsigned char spscr;
47 	unsigned char spssr;
48 	unsigned char spbr;
49 	unsigned char spdcr;
50 	unsigned char spckd;
51 	unsigned char sslnd;
52 	unsigned char spnd;
53 	unsigned char dummy0;
54 	unsigned short spcmd0;
55 	unsigned short spcmd1;
56 	unsigned short spcmd2;
57 	unsigned short spcmd3;
58 	unsigned char spbfcr;
59 	unsigned char dummy1;
60 	unsigned short spbdcr;
61 	unsigned long spbmul0;
62 	unsigned long spbmul1;
63 	unsigned long spbmul2;
64 	unsigned long spbmul3;
65 };
66 
67 struct sh_qspi_slave {
68 	struct spi_slave	slave;
69 	struct sh_qspi_regs	*regs;
70 };
71 
72 static inline struct sh_qspi_slave *to_sh_qspi(struct spi_slave *slave)
73 {
74 	return container_of(slave, struct sh_qspi_slave, slave);
75 }
76 
77 static void sh_qspi_init(struct sh_qspi_slave *ss)
78 {
79 	/* QSPI initialize */
80 	/* Set master mode only */
81 	writeb(SPCR_MSTR, &ss->regs->spcr);
82 
83 	/* Set SSL signal level */
84 	writeb(0x00, &ss->regs->sslp);
85 
86 	/* Set MOSI signal value when transfer is in idle state */
87 	writeb(SPPCR_IO3FV|SPPCR_IO2FV, &ss->regs->sppcr);
88 
89 	/* Set bit rate. See 58.3.8 Quad Serial Peripheral Interface */
90 	writeb(0x01, &ss->regs->spbr);
91 
92 	/* Disable Dummy Data Transmission */
93 	writeb(0x00, &ss->regs->spdcr);
94 
95 	/* Set clock delay value */
96 	writeb(0x00, &ss->regs->spckd);
97 
98 	/* Set SSL negation delay value */
99 	writeb(0x00, &ss->regs->sslnd);
100 
101 	/* Set next-access delay value */
102 	writeb(0x00, &ss->regs->spnd);
103 
104 	/* Set equence command */
105 	writew(SPCMD_INIT2, &ss->regs->spcmd0);
106 
107 	/* Reset transfer and receive Buffer */
108 	setbits_8(&ss->regs->spbfcr, SPBFCR_TXRST|SPBFCR_RXRST);
109 
110 	/* Clear transfer and receive Buffer control bit */
111 	clrbits_8(&ss->regs->spbfcr, SPBFCR_TXRST|SPBFCR_RXRST);
112 
113 	/* Set equence control method. Use equence0 only */
114 	writeb(0x00, &ss->regs->spscr);
115 
116 	/* Enable SPI function */
117 	setbits_8(&ss->regs->spcr, SPCR_SPE);
118 }
119 
120 int spi_cs_is_valid(unsigned int bus, unsigned int cs)
121 {
122 	return 1;
123 }
124 
125 void spi_cs_activate(struct spi_slave *slave)
126 {
127 	struct sh_qspi_slave *ss = to_sh_qspi(slave);
128 
129 	/* Set master mode only */
130 	writeb(SPCR_MSTR, &ss->regs->spcr);
131 
132 	/* Set command */
133 	writew(SPCMD_INIT1, &ss->regs->spcmd0);
134 
135 	/* Reset transfer and receive Buffer */
136 	setbits_8(&ss->regs->spbfcr, SPBFCR_TXRST|SPBFCR_RXRST);
137 
138 	/* Clear transfer and receive Buffer control bit */
139 	clrbits_8(&ss->regs->spbfcr, SPBFCR_TXRST|SPBFCR_RXRST);
140 
141 	/* Set equence control method. Use equence0 only */
142 	writeb(0x00, &ss->regs->spscr);
143 
144 	/* Enable SPI function */
145 	setbits_8(&ss->regs->spcr, SPCR_SPE);
146 }
147 
148 void spi_cs_deactivate(struct spi_slave *slave)
149 {
150 	struct sh_qspi_slave *ss = to_sh_qspi(slave);
151 
152 	/* Disable SPI Function */
153 	clrbits_8(&ss->regs->spcr, SPCR_SPE);
154 }
155 
156 void spi_init(void)
157 {
158 	/* nothing to do */
159 }
160 
161 struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
162 		unsigned int max_hz, unsigned int mode)
163 {
164 	struct sh_qspi_slave *ss;
165 
166 	if (!spi_cs_is_valid(bus, cs))
167 		return NULL;
168 
169 	ss = spi_alloc_slave(struct sh_qspi_slave, bus, cs);
170 	if (!ss) {
171 		printf("SPI_error: Fail to allocate sh_qspi_slave\n");
172 		return NULL;
173 	}
174 
175 	ss->regs = (struct sh_qspi_regs *)SH_QSPI_BASE;
176 
177 	/* Init SH QSPI */
178 	sh_qspi_init(ss);
179 
180 	return &ss->slave;
181 }
182 
183 void spi_free_slave(struct spi_slave *slave)
184 {
185 	struct sh_qspi_slave *spi = to_sh_qspi(slave);
186 
187 	free(spi);
188 }
189 
190 int spi_claim_bus(struct spi_slave *slave)
191 {
192 	return 0;
193 }
194 
195 void spi_release_bus(struct spi_slave *slave)
196 {
197 }
198 
199 int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout,
200 	     void *din, unsigned long flags)
201 {
202 	struct sh_qspi_slave *ss = to_sh_qspi(slave);
203 	unsigned long nbyte;
204 	int ret = 0;
205 	unsigned char dtdata = 0, drdata;
206 	unsigned char *tdata = &dtdata, *rdata = &drdata;
207 	unsigned long *spbmul0 = &ss->regs->spbmul0;
208 
209 	if (dout == NULL && din == NULL) {
210 		if (flags & SPI_XFER_END)
211 			spi_cs_deactivate(slave);
212 		return 0;
213 	}
214 
215 	if (bitlen % 8) {
216 		printf("%s: bitlen is not 8bit alined %d", __func__, bitlen);
217 		return 1;
218 	}
219 
220 	nbyte = bitlen / 8;
221 
222 	if (flags & SPI_XFER_BEGIN) {
223 		spi_cs_activate(slave);
224 
225 		/* Set 1048576 byte */
226 		writel(0x100000, spbmul0);
227 	}
228 
229 	if (flags & SPI_XFER_END)
230 		writel(nbyte, spbmul0);
231 
232 	if (dout != NULL)
233 		tdata = (unsigned char *)dout;
234 
235 	if (din != NULL)
236 		rdata = din;
237 
238 	while (nbyte > 0) {
239 		while (!(readb(&ss->regs->spsr) & SPSR_SPTEF)) {
240 			if (ctrlc()) {
241 				puts("abort\n");
242 				return 1;
243 			}
244 			udelay(10);
245 		}
246 
247 		writeb(*tdata, (unsigned char *)(&ss->regs->spdr));
248 
249 		while ((readw(&ss->regs->spbdcr) != SPBDCR_RXBC0)) {
250 			if (ctrlc()) {
251 				puts("abort\n");
252 				return 1;
253 			}
254 			udelay(1);
255 		}
256 
257 		while (!(readb(&ss->regs->spsr) & SPSR_SPRFF)) {
258 			if (ctrlc()) {
259 				puts("abort\n");
260 				return 1;
261 			}
262 			udelay(10);
263 		}
264 
265 		*rdata = readb((unsigned char *)(&ss->regs->spdr));
266 
267 		if (dout != NULL)
268 			tdata++;
269 		if (din != NULL)
270 			rdata++;
271 
272 		nbyte--;
273 	}
274 
275 	if (flags & SPI_XFER_END)
276 		spi_cs_deactivate(slave);
277 
278 	return ret;
279 }
280