1 /*
2 * Driver for Blackfin On-Chip SPI device
3 *
4 * Copyright (c) 2005-2008 Analog Devices Inc.
5 *
6 * Licensed under the GPL-2 or later.
7 */
8
9 /*#define DEBUG*/
10
11 #include <common.h>
12 #include <malloc.h>
13 #include <spi.h>
14
15 #include <asm/blackfin.h>
16 #include <asm/mach-common/bits/spi.h>
17
18 struct bfin_spi_slave {
19 struct spi_slave slave;
20 void *mmr_base;
21 u16 ctl, baud, flg;
22 };
23
24 #define MAKE_SPI_FUNC(mmr, off) \
25 static inline void write_##mmr(struct bfin_spi_slave *bss, u16 val) { bfin_write16(bss->mmr_base + off, val); } \
26 static inline u16 read_##mmr(struct bfin_spi_slave *bss) { return bfin_read16(bss->mmr_base + off); }
27 MAKE_SPI_FUNC(SPI_CTL, 0x00)
28 MAKE_SPI_FUNC(SPI_FLG, 0x04)
29 MAKE_SPI_FUNC(SPI_STAT, 0x08)
30 MAKE_SPI_FUNC(SPI_TDBR, 0x0c)
31 MAKE_SPI_FUNC(SPI_RDBR, 0x10)
32 MAKE_SPI_FUNC(SPI_BAUD, 0x14)
33
34 #define to_bfin_spi_slave(s) container_of(s, struct bfin_spi_slave, slave)
35
36 __attribute__((weak))
spi_cs_is_valid(unsigned int bus,unsigned int cs)37 int spi_cs_is_valid(unsigned int bus, unsigned int cs)
38 {
39 #if defined(__ADSPBF538__) || defined(__ADSPBF539__)
40 /* The SPI1/SPI2 buses are weird ... only 1 CS */
41 if (bus > 0 && cs != 1)
42 return 0;
43 #endif
44 return (cs >= 1 && cs <= 7);
45 }
46
47 __attribute__((weak))
spi_cs_activate(struct spi_slave * slave)48 void spi_cs_activate(struct spi_slave *slave)
49 {
50 struct bfin_spi_slave *bss = to_bfin_spi_slave(slave);
51 write_SPI_FLG(bss,
52 (read_SPI_FLG(bss) &
53 ~((!bss->flg << 8) << slave->cs)) |
54 (1 << slave->cs));
55 SSYNC();
56 debug("%s: SPI_FLG:%x\n", __func__, read_SPI_FLG(bss));
57 }
58
59 __attribute__((weak))
spi_cs_deactivate(struct spi_slave * slave)60 void spi_cs_deactivate(struct spi_slave *slave)
61 {
62 struct bfin_spi_slave *bss = to_bfin_spi_slave(slave);
63 u16 flg;
64
65 /* make sure we force the cs to deassert rather than let the
66 * pin float back up. otherwise, exact timings may not be
67 * met some of the time leading to random behavior (ugh).
68 */
69 flg = read_SPI_FLG(bss) | ((!bss->flg << 8) << slave->cs);
70 write_SPI_FLG(bss, flg);
71 SSYNC();
72 debug("%s: SPI_FLG:%x\n", __func__, read_SPI_FLG(bss));
73
74 flg &= ~(1 << slave->cs);
75 write_SPI_FLG(bss, flg);
76 SSYNC();
77 debug("%s: SPI_FLG:%x\n", __func__, read_SPI_FLG(bss));
78 }
79
spi_init()80 void spi_init()
81 {
82 }
83
spi_setup_slave(unsigned int bus,unsigned int cs,unsigned int max_hz,unsigned int mode)84 struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
85 unsigned int max_hz, unsigned int mode)
86 {
87 struct bfin_spi_slave *bss;
88 ulong sclk;
89 u32 mmr_base;
90 u32 baud;
91
92 if (!spi_cs_is_valid(bus, cs))
93 return NULL;
94
95 switch (bus) {
96 #ifdef SPI_CTL
97 # define SPI0_CTL SPI_CTL
98 #endif
99 case 0: mmr_base = SPI0_CTL; break;
100 #ifdef SPI1_CTL
101 case 1: mmr_base = SPI1_CTL; break;
102 #endif
103 #ifdef SPI2_CTL
104 case 2: mmr_base = SPI2_CTL; break;
105 #endif
106 default: return NULL;
107 }
108
109 sclk = get_sclk();
110 baud = sclk / (2 * max_hz);
111 /* baud should be rounded up */
112 if (sclk % (2 * max_hz))
113 baud += 1;
114 if (baud < 2)
115 baud = 2;
116 else if (baud > (u16)-1)
117 baud = -1;
118
119 bss = malloc(sizeof(*bss));
120 if (!bss)
121 return NULL;
122
123 bss->slave.bus = bus;
124 bss->slave.cs = cs;
125 bss->mmr_base = (void *)mmr_base;
126 bss->ctl = SPE | MSTR | TDBR_CORE;
127 if (mode & SPI_CPHA) bss->ctl |= CPHA;
128 if (mode & SPI_CPOL) bss->ctl |= CPOL;
129 if (mode & SPI_LSB_FIRST) bss->ctl |= LSBF;
130 bss->baud = baud;
131 bss->flg = mode & SPI_CS_HIGH ? 1 : 0;
132
133 debug("%s: bus:%i cs:%i mmr:%x ctl:%x baud:%i flg:%i\n", __func__,
134 bus, cs, mmr_base, bss->ctl, baud, bss->flg);
135
136 return &bss->slave;
137 }
138
spi_free_slave(struct spi_slave * slave)139 void spi_free_slave(struct spi_slave *slave)
140 {
141 struct bfin_spi_slave *bss = to_bfin_spi_slave(slave);
142 free(bss);
143 }
144
spi_portmux(struct spi_slave * slave)145 static void spi_portmux(struct spi_slave *slave)
146 {
147 #if defined(__ADSPBF51x__)
148 #define SET_MUX(port, mux, func) port##_mux = ((port##_mux & ~PORT_x_MUX_##mux##_MASK) | PORT_x_MUX_##mux##_FUNC_##func)
149 u16 f_mux = bfin_read_PORTF_MUX();
150 u16 f_fer = bfin_read_PORTF_FER();
151 u16 g_mux = bfin_read_PORTG_MUX();
152 u16 g_fer = bfin_read_PORTG_FER();
153 u16 h_mux = bfin_read_PORTH_MUX();
154 u16 h_fer = bfin_read_PORTH_FER();
155 switch (slave->bus) {
156 case 0:
157 /* set SCK/MISO/MOSI */
158 SET_MUX(g, 7, 1);
159 g_fer |= PG12 | PG13 | PG14;
160 switch (slave->cs) {
161 case 1: SET_MUX(f, 2, 1); f_fer |= PF7; break;
162 case 2: /* see G above */ g_fer |= PG15; break;
163 case 3: SET_MUX(h, 1, 3); f_fer |= PH4; break;
164 case 4: /* no muxing */ h_fer |= PH8; break;
165 case 5: SET_MUX(g, 1, 3); h_fer |= PG3; break;
166 case 6: /* no muxing */ break;
167 case 7: /* no muxing */ break;
168 }
169 case 1:
170 /* set SCK/MISO/MOSI */
171 SET_MUX(h, 0, 2);
172 h_fer |= PH1 | PH2 | PH3;
173 switch (slave->cs) {
174 case 1: SET_MUX(h, 2, 3); h_fer |= PH6; break;
175 case 2: SET_MUX(f, 0, 3); f_fer |= PF0; break;
176 case 3: SET_MUX(g, 0, 3); g_fer |= PG0; break;
177 case 4: SET_MUX(f, 3, 3); f_fer |= PF8; break;
178 case 5: SET_MUX(g, 6, 3); h_fer |= PG11; break;
179 case 6: /* no muxing */ break;
180 case 7: /* no muxing */ break;
181 }
182 }
183 bfin_write_PORTF_MUX(f_mux);
184 bfin_write_PORTF_FER(f_fer);
185 bfin_write_PORTG_MUX(g_mux);
186 bfin_write_PORTG_FER(g_fer);
187 bfin_write_PORTH_MUX(h_mux);
188 bfin_write_PORTH_FER(h_fer);
189 #elif defined(__ADSPBF52x__)
190 #define SET_MUX(port, mux, func) port##_mux = ((port##_mux & ~PORT_x_MUX_##mux##_MASK) | PORT_x_MUX_##mux##_FUNC_##func)
191 u16 f_mux = bfin_read_PORTF_MUX();
192 u16 f_fer = bfin_read_PORTF_FER();
193 u16 g_mux = bfin_read_PORTG_MUX();
194 u16 g_fer = bfin_read_PORTG_FER();
195 u16 h_mux = bfin_read_PORTH_MUX();
196 u16 h_fer = bfin_read_PORTH_FER();
197 /* set SCK/MISO/MOSI */
198 SET_MUX(g, 0, 3);
199 g_fer |= PG2 | PG3 | PG4;
200 switch (slave->cs) {
201 case 1: /* see G above */ g_fer |= PG1; break;
202 case 2: SET_MUX(f, 4, 3); f_fer |= PF12; break;
203 case 3: SET_MUX(f, 4, 3); f_fer |= PF13; break;
204 case 4: SET_MUX(h, 1, 1); h_fer |= PH8; break;
205 case 5: SET_MUX(h, 2, 1); h_fer |= PH9; break;
206 case 6: SET_MUX(f, 1, 3); f_fer |= PF9; break;
207 case 7: SET_MUX(f, 2, 3); f_fer |= PF10; break;
208 }
209 bfin_write_PORTF_MUX(f_mux);
210 bfin_write_PORTF_FER(f_fer);
211 bfin_write_PORTG_MUX(g_mux);
212 bfin_write_PORTG_FER(g_fer);
213 bfin_write_PORTH_MUX(h_mux);
214 bfin_write_PORTH_FER(h_fer);
215 #elif defined(__ADSPBF534__) || defined(__ADSPBF536__) || defined(__ADSPBF537__)
216 u16 mux = bfin_read_PORT_MUX();
217 u16 f_fer = bfin_read_PORTF_FER();
218 /* set SCK/MISO/MOSI */
219 f_fer |= PF11 | PF12 | PF13;
220 switch (slave->cs) {
221 case 1: f_fer |= PF10; break;
222 case 2: mux |= PJSE; break;
223 case 3: mux |= PJSE; break;
224 case 4: mux |= PFS4E; f_fer |= PF6; break;
225 case 5: mux |= PFS5E; f_fer |= PF5; break;
226 case 6: mux |= PFS6E; f_fer |= PF4; break;
227 case 7: mux |= PJCE_SPI; break;
228 }
229 bfin_write_PORT_MUX(mux);
230 bfin_write_PORTF_FER(f_fer);
231 #elif defined(__ADSPBF538__) || defined(__ADSPBF539__)
232 u16 fer, pins;
233 if (slave->bus == 1)
234 pins = PD0 | PD1 | PD2 | (slave->cs == 1 ? PD4 : 0);
235 else if (slave->bus == 2)
236 pins = PD5 | PD6 | PD7 | (slave->cs == 1 ? PD9 : 0);
237 else
238 pins = 0;
239 if (pins) {
240 fer = bfin_read_PORTDIO_FER();
241 fer &= ~pins;
242 bfin_write_PORTDIO_FER(fer);
243 }
244 #elif defined(__ADSPBF54x__)
245 #define DO_MUX(port, pin) \
246 mux = ((mux & ~PORT_x_MUX_##pin##_MASK) | PORT_x_MUX_##pin##_FUNC_1); \
247 fer |= P##port##pin;
248 u32 mux;
249 u16 fer;
250 switch (slave->bus) {
251 case 0:
252 mux = bfin_read_PORTE_MUX();
253 fer = bfin_read_PORTE_FER();
254 /* set SCK/MISO/MOSI */
255 DO_MUX(E, 0);
256 DO_MUX(E, 1);
257 DO_MUX(E, 2);
258 switch (slave->cs) {
259 case 1: DO_MUX(E, 4); break;
260 case 2: DO_MUX(E, 5); break;
261 case 3: DO_MUX(E, 6); break;
262 }
263 bfin_write_PORTE_MUX(mux);
264 bfin_write_PORTE_FER(fer);
265 break;
266 case 1:
267 mux = bfin_read_PORTG_MUX();
268 fer = bfin_read_PORTG_FER();
269 /* set SCK/MISO/MOSI */
270 DO_MUX(G, 8);
271 DO_MUX(G, 9);
272 DO_MUX(G, 10);
273 switch (slave->cs) {
274 case 1: DO_MUX(G, 5); break;
275 case 2: DO_MUX(G, 6); break;
276 case 3: DO_MUX(G, 7); break;
277 }
278 bfin_write_PORTG_MUX(mux);
279 bfin_write_PORTG_FER(fer);
280 break;
281 case 2:
282 mux = bfin_read_PORTB_MUX();
283 fer = bfin_read_PORTB_FER();
284 /* set SCK/MISO/MOSI */
285 DO_MUX(B, 12);
286 DO_MUX(B, 13);
287 DO_MUX(B, 14);
288 switch (slave->cs) {
289 case 1: DO_MUX(B, 9); break;
290 case 2: DO_MUX(B, 10); break;
291 case 3: DO_MUX(B, 11); break;
292 }
293 bfin_write_PORTB_MUX(mux);
294 bfin_write_PORTB_FER(fer);
295 break;
296 }
297 #endif
298 }
299
spi_claim_bus(struct spi_slave * slave)300 int spi_claim_bus(struct spi_slave *slave)
301 {
302 struct bfin_spi_slave *bss = to_bfin_spi_slave(slave);
303
304 debug("%s: bus:%i cs:%i\n", __func__, slave->bus, slave->cs);
305
306 spi_portmux(slave);
307 write_SPI_CTL(bss, bss->ctl);
308 write_SPI_BAUD(bss, bss->baud);
309 SSYNC();
310
311 return 0;
312 }
313
spi_release_bus(struct spi_slave * slave)314 void spi_release_bus(struct spi_slave *slave)
315 {
316 struct bfin_spi_slave *bss = to_bfin_spi_slave(slave);
317 debug("%s: bus:%i cs:%i\n", __func__, slave->bus, slave->cs);
318 write_SPI_CTL(bss, 0);
319 SSYNC();
320 }
321
322 #ifndef CONFIG_BFIN_SPI_IDLE_VAL
323 # define CONFIG_BFIN_SPI_IDLE_VAL 0xff
324 #endif
325
spi_xfer(struct spi_slave * slave,unsigned int bitlen,const void * dout,void * din,unsigned long flags)326 int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout,
327 void *din, unsigned long flags)
328 {
329 struct bfin_spi_slave *bss = to_bfin_spi_slave(slave);
330 const u8 *tx = dout;
331 u8 *rx = din;
332 uint bytes = bitlen / 8;
333 int ret = 0;
334
335 debug("%s: bus:%i cs:%i bitlen:%i bytes:%i flags:%lx\n", __func__,
336 slave->bus, slave->cs, bitlen, bytes, flags);
337
338 if (bitlen == 0)
339 goto done;
340
341 /* we can only do 8 bit transfers */
342 if (bitlen % 8) {
343 flags |= SPI_XFER_END;
344 goto done;
345 }
346
347 if (flags & SPI_XFER_BEGIN)
348 spi_cs_activate(slave);
349
350 /* todo: take advantage of hardware fifos and setup RX dma */
351 while (bytes--) {
352 u8 value = (tx ? *tx++ : CONFIG_BFIN_SPI_IDLE_VAL);
353 debug("%s: tx:%x ", __func__, value);
354 write_SPI_TDBR(bss, value);
355 SSYNC();
356 while ((read_SPI_STAT(bss) & TXS))
357 if (ctrlc()) {
358 ret = -1;
359 goto done;
360 }
361 while (!(read_SPI_STAT(bss) & SPIF))
362 if (ctrlc()) {
363 ret = -1;
364 goto done;
365 }
366 while (!(read_SPI_STAT(bss) & RXS))
367 if (ctrlc()) {
368 ret = -1;
369 goto done;
370 }
371 value = read_SPI_RDBR(bss);
372 if (rx)
373 *rx++ = value;
374 debug("rx:%x\n", value);
375 }
376
377 done:
378 if (flags & SPI_XFER_END)
379 spi_cs_deactivate(slave);
380
381 return ret;
382 }
383