imxspi.c revision 1.2.12.1 1 /* $NetBSD: imxspi.c,v 1.2.12.1 2017/08/28 17:51:30 skrll Exp $ */
2
3 /*-
4 * Copyright (c) 2014 Genetec Corporation. All rights reserved.
5 * Written by Hashimoto Kenichi for Genetec Corporation.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY GENETEC CORPORATION ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL GENETEC CORPORATION
20 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26 * POSSIBILITY OF SUCH DAMAGE.
27 */
28
29 /*
30 * this module support CSPI and eCSPI.
31 * i.MX51 have 2 eCSPI and 1 CSPI modules.
32 */
33
34 #include <sys/cdefs.h>
35 __KERNEL_RCSID(0, "$NetBSD: imxspi.c,v 1.2.12.1 2017/08/28 17:51:30 skrll Exp $");
36
37 #include "opt_imx.h"
38 #include "opt_imxspi.h"
39
40 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/kernel.h>
43 #include <sys/device.h>
44 #include <sys/errno.h>
45 #include <sys/proc.h>
46 #include <sys/intr.h>
47
48 #include <sys/bus.h>
49 #include <machine/cpu.h>
50 #include <machine/intr.h>
51
52 #include <arm/imx/imxspivar.h>
53 #include <arm/imx/imxspireg.h>
54
55 /* SPI service routines */
56 static int imxspi_configure_enhanced(void *, int, int, int);
57 static int imxspi_configure(void *, int, int, int);
58 static int imxspi_transfer(void *, struct spi_transfer *);
59 static int imxspi_intr(void *);
60
61 /* internal stuff */
62 void imxspi_done(struct imxspi_softc *, int);
63 void imxspi_send(struct imxspi_softc *);
64 void imxspi_recv(struct imxspi_softc *);
65 void imxspi_sched(struct imxspi_softc *);
66
67 #define IMXSPI(x) \
68 ((sc->sc_enhanced) ? __CONCAT(ECSPI_, x) : __CONCAT(CSPI_, x))
69 #define READ_REG(sc, x) \
70 bus_space_read_4(sc->sc_iot, sc->sc_ioh, IMXSPI(x))
71 #define WRITE_REG(sc, x, v) \
72 bus_space_write_4(sc->sc_iot, sc->sc_ioh, IMXSPI(x), (v))
73
74 #ifdef IMXSPI_DEBUG
75 int imxspi_debug = IMXSPI_DEBUG;
76 #define DPRINTFN(n,x) if (imxspi_debug>(n)) printf x;
77 #else
78 #define DPRINTFN(n,x)
79 #endif
80
81 int
82 imxspi_attach_common(device_t parent, struct imxspi_softc *sc, void *aux)
83 {
84 struct imxspi_attach_args *saa = aux;
85 struct spibus_attach_args sba;
86 bus_addr_t addr = saa->saa_addr;
87 bus_size_t size = saa->saa_size;
88
89 sc->sc_iot = saa->saa_iot;
90 sc->sc_freq = saa->saa_freq;
91 sc->sc_tag = saa->saa_tag;
92 sc->sc_enhanced = saa->saa_enhanced;
93 if (size <= 0)
94 size = SPI_SIZE;
95
96 if (bus_space_map(sc->sc_iot, addr, size, 0, &sc->sc_ioh)) {
97 aprint_error_dev(sc->sc_dev, "couldn't map registers\n");
98 return 1;
99 }
100
101 aprint_normal(": i.MX %sCSPI Controller (clock %ld Hz)\n",
102 ((sc->sc_enhanced) ? "e" : ""), sc->sc_freq);
103
104 /* Initialize SPI controller */
105 sc->sc_spi.sct_cookie = sc;
106 if (sc->sc_enhanced)
107 sc->sc_spi.sct_configure = imxspi_configure_enhanced;
108 else
109 sc->sc_spi.sct_configure = imxspi_configure;
110 sc->sc_spi.sct_transfer = imxspi_transfer;
111
112 /* sc->sc_spi.sct_nslaves must have been initialized by machdep code */
113 sc->sc_spi.sct_nslaves = saa->saa_nslaves;
114 if (!sc->sc_spi.sct_nslaves)
115 aprint_error_dev(sc->sc_dev, "no slaves!\n");
116
117 sba.sba_controller = &sc->sc_spi;
118
119 /* initialize the queue */
120 SIMPLEQ_INIT(&sc->sc_q);
121
122 /* configure SPI */
123 /* Setup Control Register */
124 WRITE_REG(sc, CONREG, __SHIFTIN(0, IMXSPI(CON_DRCTL)) |
125 __SHIFTIN(8 - 1, IMXSPI(CON_BITCOUNT)) |
126 __SHIFTIN(0xf, IMXSPI(CON_MODE)) | IMXSPI(CON_ENABLE));
127
128 /* TC and RR interruption */
129 WRITE_REG(sc, INTREG, (IMXSPI(INTR_TC_EN) | IMXSPI(INTR_RR_EN)));
130 WRITE_REG(sc, STATREG, IMXSPI(STAT_CLR));
131
132 WRITE_REG(sc, PERIODREG, 0x0);
133
134 /* enable device interrupts */
135 sc->sc_ih = intr_establish(saa->saa_irq, IPL_BIO, IST_LEVEL,
136 imxspi_intr, sc);
137
138 /* attach slave devices */
139 (void)config_found_ia(sc->sc_dev, "spibus", &sba, spibus_print);
140
141 return 0;
142 }
143
144 static int
145 imxspi_configure(void *arg, int slave, int mode, int speed)
146 {
147 struct imxspi_softc *sc = arg;
148 uint32_t div_cnt = 0;
149 uint32_t div;
150 uint32_t contrl = 0;
151
152 div = (sc->sc_freq + (speed - 1)) / speed;
153 div = div - 1;
154 for (div_cnt = 0; div > 0; div_cnt++)
155 div >>= 1;
156
157 div_cnt = div_cnt - 2;
158 if (div_cnt >= 7)
159 div_cnt = 7;
160
161 contrl = READ_REG(sc, CONREG);
162 contrl &= ~CSPI_CON_DIV;
163 contrl |= __SHIFTIN(div_cnt, CSPI_CON_DIV);
164
165 contrl &= ~(CSPI_CON_POL | CSPI_CON_PHA);
166 switch (mode) {
167 case SPI_MODE_0:
168 /* CPHA = 0, CPOL = 0 */
169 break;
170 case SPI_MODE_1:
171 /* CPHA = 1, CPOL = 0 */
172 contrl |= CSPI_CON_PHA;
173 break;
174 case SPI_MODE_2:
175 /* CPHA = 0, CPOL = 1 */
176 contrl |= CSPI_CON_POL;
177 break;
178 case SPI_MODE_3:
179 /* CPHA = 1, CPOL = 1 */
180 contrl |= CSPI_CON_POL;
181 contrl |= CSPI_CON_PHA;
182 break;
183 default:
184 return EINVAL;
185 }
186 WRITE_REG(sc, CONREG, contrl);
187
188 DPRINTFN(3, ("%s: slave %d mode %d speed %d\n",
189 __func__, slave, mode, speed));
190
191 return 0;
192 }
193
194 static int
195 imxspi_configure_enhanced(void *arg, int slave, int mode, int speed)
196 {
197 struct imxspi_softc *sc = arg;
198 uint32_t div_cnt = 0;
199 uint32_t div;
200 uint32_t contrl = 0;
201 uint32_t config = 0;
202
203 div = (sc->sc_freq + (speed - 1)) / speed;
204 for (div_cnt = 0; div > 0; div_cnt++)
205 div >>= 1;
206
207 if (div_cnt >= 15)
208 div_cnt = 15;
209
210 contrl = READ_REG(sc, CONREG);
211 contrl |= __SHIFTIN(div_cnt, ECSPI_CON_DIV);
212 contrl |= __SHIFTIN(slave, ECSPI_CON_CS);
213 contrl |= __SHIFTIN(__BIT(slave), ECSPI_CON_MODE);
214 WRITE_REG(sc, CONREG, contrl);
215
216 config = bus_space_read_4(sc->sc_iot, sc->sc_ioh, ECSPI_CONFIGREG);
217 config &= ~(__SHIFTIN(__BIT(slave), ECSPI_CONFIG_SCLK_POL) |
218 __SHIFTIN(__BIT(slave), ECSPI_CONFIG_SCLK_PHA));
219 switch (mode) {
220 case SPI_MODE_0:
221 /* CPHA = 0, CPOL = 0 */
222 break;
223 case SPI_MODE_1:
224 /* CPHA = 1, CPOL = 0 */
225 config |= __SHIFTIN(__BIT(slave), ECSPI_CONFIG_SCLK_PHA);
226 break;
227 case SPI_MODE_2:
228 /* CPHA = 0, CPOL = 1 */
229 config |= __SHIFTIN(__BIT(slave), ECSPI_CONFIG_SCLK_POL);
230 break;
231 case SPI_MODE_3:
232 /* CPHA = 1, CPOL = 1 */
233 config |= __SHIFTIN(__BIT(slave), ECSPI_CONFIG_SCLK_PHA);
234 config |= __SHIFTIN(__BIT(slave), ECSPI_CONFIG_SCLK_POL);
235 break;
236 default:
237 return EINVAL;
238 }
239 config |= __SHIFTIN(__BIT(slave), ECSPI_CONFIG_SSB_CTL);
240 bus_space_write_4(sc->sc_iot, sc->sc_ioh, ECSPI_CONFIGREG, config);
241
242 DPRINTFN(3, ("%s: slave %d mode %d speed %d\n",
243 __func__, slave, mode, speed));
244
245 return 0;
246 }
247
248 void
249 imxspi_send(struct imxspi_softc *sc)
250 {
251 uint32_t data;
252 struct spi_chunk *chunk;
253
254 /* fill the fifo */
255 while ((chunk = sc->sc_wchunk) != NULL) {
256 while (chunk->chunk_wresid) {
257 /* transmit fifo full? */
258 if (READ_REG(sc, STATREG) & IMXSPI(STAT_TF))
259 goto out;
260
261 if (chunk->chunk_wptr) {
262 data = *chunk->chunk_wptr;
263 chunk->chunk_wptr++;
264 } else {
265 data = 0xff;
266 }
267 chunk->chunk_wresid--;
268
269 WRITE_REG(sc, TXDATA, data);
270 }
271 /* advance to next transfer */
272 sc->sc_wchunk = sc->sc_wchunk->chunk_next;
273 }
274 out:
275 if (!(READ_REG(sc, STATREG) & IMXSPI(INTR_TE_EN)))
276 WRITE_REG(sc, CONREG, READ_REG(sc, CONREG) | IMXSPI(CON_XCH));
277 }
278
279 void
280 imxspi_recv(struct imxspi_softc *sc)
281 {
282 uint32_t data;
283 struct spi_chunk *chunk;
284
285 while ((chunk = sc->sc_rchunk) != NULL) {
286 while (chunk->chunk_rresid) {
287 /* rx fifo empty? */
288 if ((!(READ_REG(sc, STATREG) & IMXSPI(STAT_RR))))
289 return;
290
291 /* collect rx data */
292 data = READ_REG(sc, RXDATA);
293 if (chunk->chunk_rptr) {
294 *chunk->chunk_rptr = data & 0xff;
295 chunk->chunk_rptr++;
296 }
297
298 chunk->chunk_rresid--;
299 }
300 /* advance next to next transfer */
301 sc->sc_rchunk = sc->sc_rchunk->chunk_next;
302 }
303 }
304
305
306 void
307 imxspi_sched(struct imxspi_softc *sc)
308 {
309 struct spi_transfer *st;
310 uint32_t chipselect;
311
312 while ((st = spi_transq_first(&sc->sc_q)) != NULL) {
313 /* remove the item */
314 spi_transq_dequeue(&sc->sc_q);
315
316 /* note that we are working on it */
317 sc->sc_transfer = st;
318
319 /* chip slect */
320 if (sc->sc_tag->spi_cs_enable != NULL)
321 sc->sc_tag->spi_cs_enable(sc->sc_tag->cookie,
322 st->st_slave);
323
324 /* chip slect */
325 chipselect = READ_REG(sc, CONREG);
326 chipselect &= ~IMXSPI(CON_CS);
327 chipselect |= __SHIFTIN(st->st_slave, IMXSPI(CON_CS));
328 WRITE_REG(sc, CONREG, chipselect);
329
330 delay(1);
331
332 /* setup chunks */
333 sc->sc_rchunk = sc->sc_wchunk = st->st_chunks;
334
335 /* now kick the master start to get the chip running */
336 imxspi_send(sc);
337
338 sc->sc_running = TRUE;
339 return;
340 }
341
342 DPRINTFN(2, ("%s: nothing to do anymore\n", __func__));
343 sc->sc_running = FALSE;
344 }
345
346 void
347 imxspi_done(struct imxspi_softc *sc, int err)
348 {
349 struct spi_transfer *st;
350
351 /* called from interrupt handler */
352 if ((st = sc->sc_transfer) != NULL) {
353 if (sc->sc_tag->spi_cs_disable != NULL)
354 sc->sc_tag->spi_cs_disable(sc->sc_tag->cookie,
355 st->st_slave);
356
357 sc->sc_transfer = NULL;
358 spi_done(st, err);
359 }
360 /* make sure we clear these bits out */
361 sc->sc_wchunk = sc->sc_rchunk = NULL;
362 imxspi_sched(sc);
363 }
364
365 static int
366 imxspi_intr(void *arg)
367 {
368 struct imxspi_softc *sc = arg;
369 uint32_t intr, sr;
370 int err = 0;
371
372 if ((intr = READ_REG(sc, INTREG)) == 0) {
373 /* interrupts are not enabled, get out */
374 DPRINTFN(4, ("%s: interrupts are not enabled\n", __func__));
375 return 0;
376 }
377
378 sr = READ_REG(sc, STATREG);
379 if (!(sr & intr)) {
380 /* interrupt did not happen, get out */
381 DPRINTFN(3, ("%s: interrupts did not happen\n", __func__));
382 return 0;
383 }
384
385 /* RXFIFO ready? */
386 if (sr & IMXSPI(INTR_RR_EN)) {
387 imxspi_recv(sc);
388 if (sc->sc_wchunk == NULL && sc->sc_rchunk == NULL)
389 imxspi_done(sc, err);
390 }
391
392 /* Transfer Conplete? */
393 if (sr & IMXSPI(INTR_TC_EN)) {
394 /* complete TX */
395 imxspi_send(sc);
396 }
397
398 /* status register clear */
399 WRITE_REG(sc, STATREG, sr);
400
401 return 1;
402 }
403
404 int
405 imxspi_transfer(void *arg, struct spi_transfer *st)
406 {
407 struct imxspi_softc *sc = arg;
408 int s;
409
410 /* make sure we select the right chip */
411 s = splbio();
412 spi_transq_enqueue(&sc->sc_q, st);
413 if (sc->sc_running == FALSE)
414 imxspi_sched(sc);
415 splx(s);
416
417 return 0;
418 }
419
420