xref: /freebsd/sys/arm/freescale/imx/imx6_sdma.c (revision 5fa29797910346fc0c54829bd979856e83b9b7ea)
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(kernel_arena, (vm_offset_t)channel->bd,
200 			PAGE_SIZE);
201 
202 	return (0);
203 }
204 
205 static int
206 sdma_overrides(struct sdma_softc *sc, int chn,
207 		int evt, int host, int dsp)
208 {
209 	int reg;
210 
211 	/* Ignore sDMA requests */
212 	reg = READ4(sc, SDMAARM_EVTOVR);
213 	if (evt)
214 		reg |= (1 << chn);
215 	else
216 		reg &= ~(1 << chn);
217 	WRITE4(sc, SDMAARM_EVTOVR, reg);
218 
219 	/* Ignore enable bit (HE) */
220 	reg = READ4(sc, SDMAARM_HOSTOVR);
221 	if (host)
222 		reg |= (1 << chn);
223 	else
224 		reg &= ~(1 << chn);
225 	WRITE4(sc, SDMAARM_HOSTOVR, reg);
226 
227 	/* Prevent sDMA channel from starting */
228 	reg = READ4(sc, SDMAARM_DSPOVR);
229 	if (!dsp)
230 		reg |= (1 << chn);
231 	else
232 		reg &= ~(1 << chn);
233 	WRITE4(sc, SDMAARM_DSPOVR, reg);
234 
235 	return (0);
236 }
237 
238 int
239 sdma_configure(int chn, struct sdma_conf *conf)
240 {
241 	struct sdma_buffer_descriptor *bd0;
242 	struct sdma_buffer_descriptor *bd;
243 	struct sdma_context_data *context;
244 	struct sdma_channel *channel;
245 	struct sdma_softc *sc;
246 #if 0
247 	int timeout;
248 	int ret;
249 #endif
250 	int i;
251 
252 	sc = sdma_sc;
253 
254 	channel = &sc->channel[chn];
255 	channel->conf = conf;
256 
257 	/* Ensure operation has stopped */
258 	sdma_stop(chn);
259 
260 	/* Set priority and enable the channel */
261 	WRITE4(sc, SDMAARM_SDMA_CHNPRI(chn), 1);
262 	WRITE4(sc, SDMAARM_CHNENBL(conf->event), (1 << chn));
263 
264 	sdma_overrides(sc, chn, 0, 0, 0);
265 
266 	if (conf->num_bd > MAX_BD) {
267 		device_printf(sc->dev, "Error: too much buffer"
268 				" descriptors requested\n");
269 		return (-1);
270 	}
271 
272 	for (i = 0; i < conf->num_bd; i++) {
273 		bd = &channel->bd[i];
274 		bd->mode.command = conf->command;
275 		bd->mode.status = BD_DONE | BD_EXTD | BD_CONT | BD_INTR;
276 		if (i == (conf->num_bd - 1))
277 			bd->mode.status |= BD_WRAP;
278 		bd->mode.count = conf->period;
279 		bd->buffer_addr = conf->saddr + (conf->period * i);
280 		bd->ext_buffer_addr = 0;
281 	}
282 
283 	sc->ccb[chn].base_bd_ptr = vtophys(channel->bd);
284 	sc->ccb[chn].current_bd_ptr = vtophys(channel->bd);
285 
286 	/*
287 	 * Load context.
288 	 *
289 	 * i.MX6 Reference Manual: Appendix A SDMA Scripts
290 	 * A.3.1.7.1 (mcu_2_app)
291 	 */
292 
293 	/*
294 	 * TODO: allow using other scripts
295 	 */
296 	context = sc->context;
297 	memset(context, 0, sizeof(*context));
298 	context->channel_state.pc = sc->fw_scripts->mcu_2_app_addr;
299 
300 	/*
301 	 * Tx FIFO 0 address (r6)
302 	 * Event_mask (r1)
303 	 * Event2_mask (r0)
304 	 * Watermark level (r7)
305 	 */
306 
307 	if (conf->event > 32) {
308 		context->gReg[0] = (1 << (conf->event % 32));
309 		context->gReg[1] = 0;
310 	} else {
311 		context->gReg[0] = 0;
312 		context->gReg[1] = (1 << conf->event);
313 	}
314 
315 	context->gReg[6] = conf->daddr;
316 	context->gReg[7] = conf->word_length;
317 
318 	bd0 = sc->bd0;
319 	bd0->mode.command = C0_SETDM;
320 	bd0->mode.status = BD_DONE | BD_INTR | BD_WRAP | BD_EXTD;
321 	bd0->mode.count = sizeof(*context) / 4;
322 	bd0->buffer_addr = sc->context_phys;
323 	bd0->ext_buffer_addr = 2048 + (sizeof(*context) / 4) * chn;
324 
325 	WRITE4(sc, SDMAARM_HSTART, 1);
326 
327 #if 0
328 	/* Debug purposes */
329 
330 	timeout = 1000;
331 	while (!(ret = READ4(sc, SDMAARM_INTR) & 1)) {
332 		if (timeout-- <= 0)
333 			break;
334 		DELAY(10);
335 	};
336 
337 	if (!ret) {
338 		device_printf(sc->dev, "Failed to load context.\n");
339 		return (-1);
340 	}
341 
342 	WRITE4(sc, SDMAARM_INTR, ret);
343 
344 	device_printf(sc->dev, "Context loaded successfully.\n");
345 #endif
346 
347 	return (0);
348 }
349 
350 static int
351 load_firmware(struct sdma_softc *sc)
352 {
353 	const struct sdma_firmware_header *header;
354 	const struct firmware *fp;
355 
356 	fp = firmware_get("sdma_fw");
357 	if (fp == NULL) {
358 		device_printf(sc->dev, "Can't get firmware.\n");
359 		return (-1);
360 	}
361 
362 	header = fp->data;
363 	if (header->magic != FW_HEADER_MAGIC) {
364 		device_printf(sc->dev, "Can't use firmware.\n");
365 		return (-1);
366 	}
367 
368 	sc->fw_header = header;
369 	sc->fw_scripts = (const void *)((const char *)header +
370 				header->script_addrs_start);
371 
372 	return (0);
373 }
374 
375 static int
376 boot_firmware(struct sdma_softc *sc)
377 {
378 	struct sdma_buffer_descriptor *bd0;
379 	const uint32_t *ram_code;
380 	int timeout;
381 	int ret;
382 	int chn;
383 	int sz;
384 	int i;
385 
386 	ram_code = (const void *)((const char *)sc->fw_header +
387 			sc->fw_header->ram_code_start);
388 
389 	/* Make sure SDMA has not started yet */
390 	WRITE4(sc, SDMAARM_MC0PTR, 0);
391 
392 	sz = SDMA_N_CHANNELS * sizeof(struct sdma_channel_control) + \
393 	    sizeof(struct sdma_context_data);
394 	sc->ccb = (void *)kmem_alloc_contig(sz, M_ZERO, 0, ~0, PAGE_SIZE, 0,
395 	    VM_MEMATTR_UNCACHEABLE);
396 	sc->ccb_phys = vtophys(sc->ccb);
397 
398 	sc->context = (void *)((char *)sc->ccb + \
399 	    SDMA_N_CHANNELS * sizeof(struct sdma_channel_control));
400 	sc->context_phys = vtophys(sc->context);
401 
402 	/* Disable all the channels */
403 	for (i = 0; i < SDMA_N_EVENTS; i++)
404 		WRITE4(sc, SDMAARM_CHNENBL(i), 0);
405 
406 	/* All channels have priority 0 */
407 	for (i = 0; i < SDMA_N_CHANNELS; i++)
408 		WRITE4(sc, SDMAARM_SDMA_CHNPRI(i), 0);
409 
410 	/* Channel 0 is used for booting firmware */
411 	chn = 0;
412 
413 	sc->bd0 = (void *)kmem_alloc_contig(PAGE_SIZE, M_ZERO, 0, ~0, PAGE_SIZE,
414 	    0, VM_MEMATTR_UNCACHEABLE);
415 	bd0 = sc->bd0;
416 	sc->ccb[chn].base_bd_ptr = vtophys(bd0);
417 	sc->ccb[chn].current_bd_ptr = vtophys(bd0);
418 
419 	WRITE4(sc, SDMAARM_SDMA_CHNPRI(chn), 1);
420 
421 	sdma_overrides(sc, chn, 1, 0, 0);
422 
423 	/* XXX: not sure what is that */
424 	WRITE4(sc, SDMAARM_CHN0ADDR, 0x4050);
425 
426 	WRITE4(sc, SDMAARM_CONFIG, 0);
427 	WRITE4(sc, SDMAARM_MC0PTR, sc->ccb_phys);
428 	WRITE4(sc, SDMAARM_CONFIG, CONFIG_CSM);
429 	WRITE4(sc, SDMAARM_SDMA_CHNPRI(chn), 1);
430 
431 	bd0->mode.command = C0_SETPM;
432 	bd0->mode.status = BD_DONE | BD_INTR | BD_WRAP | BD_EXTD;
433 	bd0->mode.count = sc->fw_header->ram_code_size / 2;
434 	bd0->buffer_addr = vtophys(ram_code);
435 	bd0->ext_buffer_addr = sc->fw_scripts->ram_code_start_addr;
436 
437 	WRITE4(sc, SDMAARM_HSTART, 1);
438 
439 	timeout = 100;
440 	while (!(ret = READ4(sc, SDMAARM_INTR) & 1)) {
441 		if (timeout-- <= 0)
442 			break;
443 		DELAY(10);
444 	}
445 
446 	if (ret == 0) {
447 		device_printf(sc->dev, "SDMA failed to boot\n");
448 		return (-1);
449 	}
450 
451 	WRITE4(sc, SDMAARM_INTR, ret);
452 
453 #if 0
454 	device_printf(sc->dev, "SDMA booted successfully.\n");
455 #endif
456 
457 	/* Debug is disabled */
458 	WRITE4(sc, SDMAARM_ONCE_ENB, 0);
459 
460 	return (0);
461 }
462 
463 static int
464 sdma_attach(device_t dev)
465 {
466 	struct sdma_softc *sc;
467 	int err;
468 
469 	sc = device_get_softc(dev);
470 	sc->dev = dev;
471 
472 	if (bus_alloc_resources(dev, sdma_spec, sc->res)) {
473 		device_printf(dev, "could not allocate resources\n");
474 		return (ENXIO);
475 	}
476 
477 	/* Memory interface */
478 	sc->bst = rman_get_bustag(sc->res[0]);
479 	sc->bsh = rman_get_bushandle(sc->res[0]);
480 
481 	sdma_sc = sc;
482 
483 	/* Setup interrupt handler */
484 	err = bus_setup_intr(dev, sc->res[1], INTR_TYPE_MISC | INTR_MPSAFE,
485 	    NULL, sdma_intr, sc, &sc->ih);
486 	if (err) {
487 		device_printf(dev, "Unable to alloc interrupt resource.\n");
488 		return (ENXIO);
489 	}
490 
491 	if (load_firmware(sc) == -1)
492 		return (ENXIO);
493 
494 	if (boot_firmware(sc) == -1)
495 		return (ENXIO);
496 
497 	return (0);
498 };
499 
500 static device_method_t sdma_methods[] = {
501 	/* Device interface */
502 	DEVMETHOD(device_probe,		sdma_probe),
503 	DEVMETHOD(device_attach,	sdma_attach),
504 	{ 0, 0 }
505 };
506 
507 static driver_t sdma_driver = {
508 	"sdma",
509 	sdma_methods,
510 	sizeof(struct sdma_softc),
511 };
512 
513 static devclass_t sdma_devclass;
514 
515 EARLY_DRIVER_MODULE(sdma, simplebus, sdma_driver, sdma_devclass, 0, 0,
516     BUS_PASS_RESOURCE);
517