xref: /freebsd/sys/arm/freescale/imx/imx6_sdma.c (revision 62cfcf62f627e5093fb37026a6d8c98e4d2ef04c)
1 /*-
2  * Copyright (c) 2015 Ruslan Bukin <br@bsdpad.com>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 /*
28  * i.MX6 Smart Direct Memory Access Controller (sDMA)
29  * Chapter 41, i.MX 6Dual/6Quad Applications Processor Reference Manual,
30  * Rev. 1, 04/2013
31  */
32 
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
35 
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/bus.h>
39 #include <sys/kernel.h>
40 #include <sys/module.h>
41 #include <sys/malloc.h>
42 #include <sys/endian.h>
43 #include <sys/rman.h>
44 #include <sys/timeet.h>
45 #include <sys/timetc.h>
46 #include <sys/firmware.h>
47 
48 #include <vm/vm.h>
49 #include <vm/vm_extern.h>
50 #include <vm/vm_kern.h>
51 #include <vm/pmap.h>
52 
53 #include <dev/ofw/openfirm.h>
54 #include <dev/ofw/ofw_bus.h>
55 #include <dev/ofw/ofw_bus_subr.h>
56 
57 #include <machine/bus.h>
58 #include <machine/cpu.h>
59 #include <machine/intr.h>
60 
61 #include <arm/freescale/imx/imx6_sdma.h>
62 
63 #define	MAX_BD	(PAGE_SIZE / sizeof(struct sdma_buffer_descriptor))
64 
65 #define	READ4(_sc, _reg)	\
66 	bus_space_read_4(_sc->bst, _sc->bsh, _reg)
67 #define	WRITE4(_sc, _reg, _val)	\
68 	bus_space_write_4(_sc->bst, _sc->bsh, _reg, _val)
69 
70 struct sdma_softc *sdma_sc;
71 
72 static struct resource_spec sdma_spec[] = {
73 	{ SYS_RES_MEMORY,	0,	RF_ACTIVE },
74 	{ SYS_RES_IRQ,		0,	RF_ACTIVE },
75 	{ -1, 0 }
76 };
77 
78 static void
79 sdma_intr(void *arg)
80 {
81 	struct sdma_buffer_descriptor *bd;
82 	struct sdma_channel *channel;
83 	struct sdma_conf *conf;
84 	struct sdma_softc *sc;
85 	int pending;
86 	int i;
87 	int j;
88 
89 	sc = arg;
90 
91 	pending = READ4(sc, SDMAARM_INTR);
92 
93 	/* Ack intr */
94 	WRITE4(sc, SDMAARM_INTR, pending);
95 
96 	for (i = 0; i < SDMA_N_CHANNELS; i++) {
97 		if ((pending & (1 << i)) == 0)
98 			continue;
99 		channel = &sc->channel[i];
100 		conf = channel->conf;
101 		if (!conf)
102 			continue;
103 		for (j = 0; j < conf->num_bd; j++) {
104 			bd = &channel->bd[j];
105 			bd->mode.status |= BD_DONE;
106 			if (bd->mode.status & BD_RROR)
107 				printf("sDMA error\n");
108 		}
109 
110 		conf->ih(conf->ih_user, 1);
111 
112 		WRITE4(sc, SDMAARM_HSTART, (1 << i));
113 	}
114 }
115 
116 static int
117 sdma_probe(device_t dev)
118 {
119 
120 	if (!ofw_bus_status_okay(dev))
121 		return (ENXIO);
122 
123 	if (!ofw_bus_is_compatible(dev, "fsl,imx6q-sdma"))
124 		return (ENXIO);
125 
126 	device_set_desc(dev, "i.MX6 Smart Direct Memory Access Controller");
127 	return (BUS_PROBE_DEFAULT);
128 }
129 
130 int
131 sdma_start(int chn)
132 {
133 	struct sdma_softc *sc;
134 
135 	sc = sdma_sc;
136 
137 	WRITE4(sc, SDMAARM_HSTART, (1 << chn));
138 
139 	return (0);
140 }
141 
142 int
143 sdma_stop(int chn)
144 {
145 	struct sdma_softc *sc;
146 
147 	sc = sdma_sc;
148 
149 	WRITE4(sc, SDMAARM_STOP_STAT, (1 << chn));
150 
151 	return (0);
152 }
153 
154 int
155 sdma_alloc(void)
156 {
157 	struct sdma_channel *channel;
158 	struct sdma_softc *sc;
159 	int found;
160 	int chn;
161 	int i;
162 
163 	sc = sdma_sc;
164 	found = 0;
165 
166 	/* Channel 0 can't be used */
167 	for (i = 1; i < SDMA_N_CHANNELS; i++) {
168 		channel = &sc->channel[i];
169 		if (channel->in_use == 0) {
170 			channel->in_use = 1;
171 			found = 1;
172 			break;
173 		}
174 	}
175 
176 	if (!found)
177 		return (-1);
178 
179 	chn = i;
180 
181 	/* Allocate area for buffer descriptors */
182 	channel->bd = (void *)kmem_alloc_contig(PAGE_SIZE, M_ZERO, 0, ~0,
183 	    PAGE_SIZE, 0, VM_MEMATTR_UNCACHEABLE);
184 
185 	return (chn);
186 }
187 
188 int
189 sdma_free(int chn)
190 {
191 	struct sdma_channel *channel;
192 	struct sdma_softc *sc;
193 
194 	sc = sdma_sc;
195 
196 	channel = &sc->channel[chn];
197 	channel->in_use = 0;
198 
199 	kmem_free((vm_offset_t)channel->bd, PAGE_SIZE);
200 
201 	return (0);
202 }
203 
204 static int
205 sdma_overrides(struct sdma_softc *sc, int chn,
206 		int evt, int host, int dsp)
207 {
208 	int reg;
209 
210 	/* Ignore sDMA requests */
211 	reg = READ4(sc, SDMAARM_EVTOVR);
212 	if (evt)
213 		reg |= (1 << chn);
214 	else
215 		reg &= ~(1 << chn);
216 	WRITE4(sc, SDMAARM_EVTOVR, reg);
217 
218 	/* Ignore enable bit (HE) */
219 	reg = READ4(sc, SDMAARM_HOSTOVR);
220 	if (host)
221 		reg |= (1 << chn);
222 	else
223 		reg &= ~(1 << chn);
224 	WRITE4(sc, SDMAARM_HOSTOVR, reg);
225 
226 	/* Prevent sDMA channel from starting */
227 	reg = READ4(sc, SDMAARM_DSPOVR);
228 	if (!dsp)
229 		reg |= (1 << chn);
230 	else
231 		reg &= ~(1 << chn);
232 	WRITE4(sc, SDMAARM_DSPOVR, reg);
233 
234 	return (0);
235 }
236 
237 int
238 sdma_configure(int chn, struct sdma_conf *conf)
239 {
240 	struct sdma_buffer_descriptor *bd0;
241 	struct sdma_buffer_descriptor *bd;
242 	struct sdma_context_data *context;
243 	struct sdma_channel *channel;
244 	struct sdma_softc *sc;
245 #if 0
246 	int timeout;
247 	int ret;
248 #endif
249 	int i;
250 
251 	sc = sdma_sc;
252 
253 	channel = &sc->channel[chn];
254 	channel->conf = conf;
255 
256 	/* Ensure operation has stopped */
257 	sdma_stop(chn);
258 
259 	/* Set priority and enable the channel */
260 	WRITE4(sc, SDMAARM_SDMA_CHNPRI(chn), 1);
261 	WRITE4(sc, SDMAARM_CHNENBL(conf->event), (1 << chn));
262 
263 	sdma_overrides(sc, chn, 0, 0, 0);
264 
265 	if (conf->num_bd > MAX_BD) {
266 		device_printf(sc->dev, "Error: too much buffer"
267 				" descriptors requested\n");
268 		return (-1);
269 	}
270 
271 	for (i = 0; i < conf->num_bd; i++) {
272 		bd = &channel->bd[i];
273 		bd->mode.command = conf->command;
274 		bd->mode.status = BD_DONE | BD_EXTD | BD_CONT | BD_INTR;
275 		if (i == (conf->num_bd - 1))
276 			bd->mode.status |= BD_WRAP;
277 		bd->mode.count = conf->period;
278 		bd->buffer_addr = conf->saddr + (conf->period * i);
279 		bd->ext_buffer_addr = 0;
280 	}
281 
282 	sc->ccb[chn].base_bd_ptr = vtophys(channel->bd);
283 	sc->ccb[chn].current_bd_ptr = vtophys(channel->bd);
284 
285 	/*
286 	 * Load context.
287 	 *
288 	 * i.MX6 Reference Manual: Appendix A SDMA Scripts
289 	 * A.3.1.7.1 (mcu_2_app)
290 	 */
291 
292 	/*
293 	 * TODO: allow using other scripts
294 	 */
295 	context = sc->context;
296 	memset(context, 0, sizeof(*context));
297 	context->channel_state.pc = sc->fw_scripts->mcu_2_app_addr;
298 
299 	/*
300 	 * Tx FIFO 0 address (r6)
301 	 * Event_mask (r1)
302 	 * Event2_mask (r0)
303 	 * Watermark level (r7)
304 	 */
305 
306 	if (conf->event > 32) {
307 		context->gReg[0] = (1 << (conf->event % 32));
308 		context->gReg[1] = 0;
309 	} else {
310 		context->gReg[0] = 0;
311 		context->gReg[1] = (1 << conf->event);
312 	}
313 
314 	context->gReg[6] = conf->daddr;
315 	context->gReg[7] = conf->word_length;
316 
317 	bd0 = sc->bd0;
318 	bd0->mode.command = C0_SETDM;
319 	bd0->mode.status = BD_DONE | BD_INTR | BD_WRAP | BD_EXTD;
320 	bd0->mode.count = sizeof(*context) / 4;
321 	bd0->buffer_addr = sc->context_phys;
322 	bd0->ext_buffer_addr = 2048 + (sizeof(*context) / 4) * chn;
323 
324 	WRITE4(sc, SDMAARM_HSTART, 1);
325 
326 #if 0
327 	/* Debug purposes */
328 
329 	timeout = 1000;
330 	while (!(ret = READ4(sc, SDMAARM_INTR) & 1)) {
331 		if (timeout-- <= 0)
332 			break;
333 		DELAY(10);
334 	};
335 
336 	if (!ret) {
337 		device_printf(sc->dev, "Failed to load context.\n");
338 		return (-1);
339 	}
340 
341 	WRITE4(sc, SDMAARM_INTR, ret);
342 
343 	device_printf(sc->dev, "Context loaded successfully.\n");
344 #endif
345 
346 	return (0);
347 }
348 
349 static int
350 load_firmware(struct sdma_softc *sc)
351 {
352 	const struct sdma_firmware_header *header;
353 	const struct firmware *fp;
354 
355 	fp = firmware_get("sdma_fw");
356 	if (fp == NULL) {
357 		device_printf(sc->dev, "Can't get firmware.\n");
358 		return (-1);
359 	}
360 
361 	header = fp->data;
362 	if (header->magic != FW_HEADER_MAGIC) {
363 		device_printf(sc->dev, "Can't use firmware.\n");
364 		return (-1);
365 	}
366 
367 	sc->fw_header = header;
368 	sc->fw_scripts = (const void *)((const char *)header +
369 				header->script_addrs_start);
370 
371 	return (0);
372 }
373 
374 static int
375 boot_firmware(struct sdma_softc *sc)
376 {
377 	struct sdma_buffer_descriptor *bd0;
378 	const uint32_t *ram_code;
379 	int timeout;
380 	int ret;
381 	int chn;
382 	int sz;
383 	int i;
384 
385 	ram_code = (const void *)((const char *)sc->fw_header +
386 			sc->fw_header->ram_code_start);
387 
388 	/* Make sure SDMA has not started yet */
389 	WRITE4(sc, SDMAARM_MC0PTR, 0);
390 
391 	sz = SDMA_N_CHANNELS * sizeof(struct sdma_channel_control) + \
392 	    sizeof(struct sdma_context_data);
393 	sc->ccb = (void *)kmem_alloc_contig(sz, M_ZERO, 0, ~0, PAGE_SIZE, 0,
394 	    VM_MEMATTR_UNCACHEABLE);
395 	sc->ccb_phys = vtophys(sc->ccb);
396 
397 	sc->context = (void *)((char *)sc->ccb + \
398 	    SDMA_N_CHANNELS * sizeof(struct sdma_channel_control));
399 	sc->context_phys = vtophys(sc->context);
400 
401 	/* Disable all the channels */
402 	for (i = 0; i < SDMA_N_EVENTS; i++)
403 		WRITE4(sc, SDMAARM_CHNENBL(i), 0);
404 
405 	/* All channels have priority 0 */
406 	for (i = 0; i < SDMA_N_CHANNELS; i++)
407 		WRITE4(sc, SDMAARM_SDMA_CHNPRI(i), 0);
408 
409 	/* Channel 0 is used for booting firmware */
410 	chn = 0;
411 
412 	sc->bd0 = (void *)kmem_alloc_contig(PAGE_SIZE, M_ZERO, 0, ~0, PAGE_SIZE,
413 	    0, VM_MEMATTR_UNCACHEABLE);
414 	bd0 = sc->bd0;
415 	sc->ccb[chn].base_bd_ptr = vtophys(bd0);
416 	sc->ccb[chn].current_bd_ptr = vtophys(bd0);
417 
418 	WRITE4(sc, SDMAARM_SDMA_CHNPRI(chn), 1);
419 
420 	sdma_overrides(sc, chn, 1, 0, 0);
421 
422 	/* XXX: not sure what is that */
423 	WRITE4(sc, SDMAARM_CHN0ADDR, 0x4050);
424 
425 	WRITE4(sc, SDMAARM_CONFIG, 0);
426 	WRITE4(sc, SDMAARM_MC0PTR, sc->ccb_phys);
427 	WRITE4(sc, SDMAARM_CONFIG, CONFIG_CSM);
428 	WRITE4(sc, SDMAARM_SDMA_CHNPRI(chn), 1);
429 
430 	bd0->mode.command = C0_SETPM;
431 	bd0->mode.status = BD_DONE | BD_INTR | BD_WRAP | BD_EXTD;
432 	bd0->mode.count = sc->fw_header->ram_code_size / 2;
433 	bd0->buffer_addr = vtophys(ram_code);
434 	bd0->ext_buffer_addr = sc->fw_scripts->ram_code_start_addr;
435 
436 	WRITE4(sc, SDMAARM_HSTART, 1);
437 
438 	timeout = 100;
439 	while (!(ret = READ4(sc, SDMAARM_INTR) & 1)) {
440 		if (timeout-- <= 0)
441 			break;
442 		DELAY(10);
443 	}
444 
445 	if (ret == 0) {
446 		device_printf(sc->dev, "SDMA failed to boot\n");
447 		return (-1);
448 	}
449 
450 	WRITE4(sc, SDMAARM_INTR, ret);
451 
452 #if 0
453 	device_printf(sc->dev, "SDMA booted successfully.\n");
454 #endif
455 
456 	/* Debug is disabled */
457 	WRITE4(sc, SDMAARM_ONCE_ENB, 0);
458 
459 	return (0);
460 }
461 
462 static int
463 sdma_attach(device_t dev)
464 {
465 	struct sdma_softc *sc;
466 	int err;
467 
468 	sc = device_get_softc(dev);
469 	sc->dev = dev;
470 
471 	if (bus_alloc_resources(dev, sdma_spec, sc->res)) {
472 		device_printf(dev, "could not allocate resources\n");
473 		return (ENXIO);
474 	}
475 
476 	/* Memory interface */
477 	sc->bst = rman_get_bustag(sc->res[0]);
478 	sc->bsh = rman_get_bushandle(sc->res[0]);
479 
480 	sdma_sc = sc;
481 
482 	/* Setup interrupt handler */
483 	err = bus_setup_intr(dev, sc->res[1], INTR_TYPE_MISC | INTR_MPSAFE,
484 	    NULL, sdma_intr, sc, &sc->ih);
485 	if (err) {
486 		device_printf(dev, "Unable to alloc interrupt resource.\n");
487 		return (ENXIO);
488 	}
489 
490 	if (load_firmware(sc) == -1)
491 		return (ENXIO);
492 
493 	if (boot_firmware(sc) == -1)
494 		return (ENXIO);
495 
496 	return (0);
497 };
498 
499 static device_method_t sdma_methods[] = {
500 	/* Device interface */
501 	DEVMETHOD(device_probe,		sdma_probe),
502 	DEVMETHOD(device_attach,	sdma_attach),
503 	{ 0, 0 }
504 };
505 
506 static driver_t sdma_driver = {
507 	"sdma",
508 	sdma_methods,
509 	sizeof(struct sdma_softc),
510 };
511 
512 static devclass_t sdma_devclass;
513 
514 EARLY_DRIVER_MODULE(sdma, simplebus, sdma_driver, sdma_devclass, 0, 0,
515     BUS_PASS_RESOURCE);
516