xref: /freebsd/sys/dev/xilinx/axidma.c (revision b9f654b163bce26de79705e77b872427c9f2afa1)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2019 Ruslan Bukin <br@bsdpad.com>
5  *
6  * This software was developed by SRI International and the University of
7  * Cambridge Computer Laboratory (Department of Computer Science and
8  * Technology) under DARPA contract HR0011-18-C-0016 ("ECATS"), as part of the
9  * DARPA SSITH research programme.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 /* Xilinx AXI DMA controller driver. */
34 
35 #include <sys/cdefs.h>
36 __FBSDID("$FreeBSD$");
37 
38 #include "opt_platform.h"
39 #include <sys/param.h>
40 #include <sys/systm.h>
41 #include <sys/conf.h>
42 #include <sys/bus.h>
43 #include <sys/kernel.h>
44 #include <sys/module.h>
45 #include <sys/rman.h>
46 
47 #include <machine/bus.h>
48 
49 #include <vm/vm.h>
50 #include <vm/vm_extern.h>
51 #include <vm/vm_page.h>
52 
53 #ifdef FDT
54 #include <dev/fdt/fdt_common.h>
55 #include <dev/ofw/ofw_bus.h>
56 #include <dev/ofw/ofw_bus_subr.h>
57 #endif
58 
59 #include <dev/xdma/xdma.h>
60 #include <dev/xilinx/axidma.h>
61 
62 #include "xdma_if.h"
63 
64 #define AXIDMA_DEBUG
65 #undef AXIDMA_DEBUG
66 
67 #ifdef AXIDMA_DEBUG
68 #define dprintf(fmt, ...)  printf(fmt, ##__VA_ARGS__)
69 #else
70 #define dprintf(fmt, ...)
71 #endif
72 
73 #define	AXIDMA_NCHANNELS	2
74 #define	AXIDMA_DESCS_NUM	512
75 #define	AXIDMA_TX_CHAN		0
76 #define	AXIDMA_RX_CHAN		1
77 
78 extern struct bus_space memmap_bus;
79 
80 struct axidma_fdt_data {
81 	int id;
82 };
83 
84 struct axidma_channel {
85 	struct axidma_softc	*sc;
86 	xdma_channel_t		*xchan;
87 	bool			used;
88 	int			idx_head;
89 	int			idx_tail;
90 
91 	struct axidma_desc	**descs;
92 	vm_paddr_t		*descs_phys;
93 	uint32_t		descs_num;
94 
95 	vm_size_t		mem_size;
96 	vm_offset_t		mem_paddr;
97 	vm_offset_t		mem_vaddr;
98 
99 	uint32_t		descs_used_count;
100 };
101 
102 struct axidma_softc {
103 	device_t		dev;
104 	struct resource		*res[3];
105 	bus_space_tag_t		bst;
106 	bus_space_handle_t	bsh;
107 	void			*ih[2];
108 	struct axidma_desc	desc;
109 	struct axidma_channel	channels[AXIDMA_NCHANNELS];
110 };
111 
112 static struct resource_spec axidma_spec[] = {
113 	{ SYS_RES_MEMORY,	0,	RF_ACTIVE },
114 	{ SYS_RES_IRQ,		0,	RF_ACTIVE },
115 	{ SYS_RES_IRQ,		1,	RF_ACTIVE },
116 	{ -1, 0 }
117 };
118 
119 #define	HWTYPE_NONE	0
120 #define	HWTYPE_STD	1
121 
122 static struct ofw_compat_data compat_data[] = {
123 	{ "xlnx,eth-dma",	HWTYPE_STD },
124 	{ NULL,			HWTYPE_NONE },
125 };
126 
127 static int axidma_probe(device_t dev);
128 static int axidma_attach(device_t dev);
129 static int axidma_detach(device_t dev);
130 
131 static inline uint32_t
132 axidma_next_desc(struct axidma_channel *chan, uint32_t curidx)
133 {
134 
135 	return ((curidx + 1) % chan->descs_num);
136 }
137 
138 static void
139 axidma_intr(struct axidma_softc *sc,
140     struct axidma_channel *chan)
141 {
142 	xdma_transfer_status_t status;
143 	xdma_transfer_status_t st;
144 	struct axidma_fdt_data *data;
145 	xdma_controller_t *xdma;
146 	struct axidma_desc *desc;
147 	struct xdma_channel *xchan;
148 	uint32_t tot_copied;
149 	int pending;
150 	int errors;
151 
152 	xchan = chan->xchan;
153 	xdma = xchan->xdma;
154 	data = xdma->data;
155 
156 	pending = READ4(sc, AXI_DMASR(data->id));
157 	WRITE4(sc, AXI_DMASR(data->id), pending);
158 
159 	errors = (pending & (DMASR_DMAINTERR | DMASR_DMASLVERR
160 			| DMASR_DMADECOREERR | DMASR_SGINTERR
161 			| DMASR_SGSLVERR | DMASR_SGDECERR));
162 
163 	dprintf("%s: AXI_DMASR %x\n", __func__,
164 	    READ4(sc, AXI_DMASR(data->id)));
165 	dprintf("%s: AXI_CURDESC %x\n", __func__,
166 	    READ4(sc, AXI_CURDESC(data->id)));
167 	dprintf("%s: AXI_TAILDESC %x\n", __func__,
168 	    READ4(sc, AXI_TAILDESC(data->id)));
169 
170 	tot_copied = 0;
171 
172 	while (chan->idx_tail != chan->idx_head) {
173 		desc = chan->descs[chan->idx_tail];
174 		if ((desc->status & BD_STATUS_CMPLT) == 0)
175 			break;
176 
177 		st.error = errors;
178 		st.transferred = desc->status & BD_CONTROL_LEN_M;
179 		tot_copied += st.transferred;
180 		xchan_seg_done(xchan, &st);
181 
182 		chan->idx_tail = axidma_next_desc(chan, chan->idx_tail);
183 		atomic_subtract_int(&chan->descs_used_count, 1);
184 	}
185 
186 	/* Finish operation */
187 	status.error = errors;
188 	status.transferred = tot_copied;
189 	xdma_callback(chan->xchan, &status);
190 }
191 
192 static void
193 axidma_intr_rx(void *arg)
194 {
195 	struct axidma_softc *sc;
196 	struct axidma_channel *chan;
197 
198 	dprintf("%s\n", __func__);
199 
200 	sc = arg;
201 	chan = &sc->channels[AXIDMA_RX_CHAN];
202 
203 	axidma_intr(sc, chan);
204 }
205 
206 static void
207 axidma_intr_tx(void *arg)
208 {
209 	struct axidma_softc *sc;
210 	struct axidma_channel *chan;
211 
212 	dprintf("%s\n", __func__);
213 
214 	sc = arg;
215 	chan = &sc->channels[AXIDMA_TX_CHAN];
216 
217 	axidma_intr(sc, chan);
218 }
219 
220 static int
221 axidma_reset(struct axidma_softc *sc, int chan_id)
222 {
223 	int timeout;
224 
225 	WRITE4(sc, AXI_DMACR(chan_id), DMACR_RESET);
226 
227 	timeout = 100;
228 	do {
229 		if ((READ4(sc, AXI_DMACR(chan_id)) & DMACR_RESET) == 0)
230 			break;
231 	} while (timeout--);
232 
233 	dprintf("timeout %d\n", timeout);
234 
235 	if (timeout == 0)
236 		return (-1);
237 
238 	dprintf("%s: read control after reset: %x\n",
239 	    __func__, READ4(sc, AXI_DMACR(chan_id)));
240 
241 	return (0);
242 }
243 
244 static int
245 axidma_probe(device_t dev)
246 {
247 	int hwtype;
248 
249 	if (!ofw_bus_status_okay(dev))
250 		return (ENXIO);
251 
252 	hwtype = ofw_bus_search_compatible(dev, compat_data)->ocd_data;
253 	if (hwtype == HWTYPE_NONE)
254 		return (ENXIO);
255 
256 	device_set_desc(dev, "Xilinx AXI DMA");
257 
258 	return (BUS_PROBE_DEFAULT);
259 }
260 
261 static int
262 axidma_attach(device_t dev)
263 {
264 	struct axidma_softc *sc;
265 	phandle_t xref, node;
266 	int err;
267 
268 	sc = device_get_softc(dev);
269 	sc->dev = dev;
270 
271 	if (bus_alloc_resources(dev, axidma_spec, sc->res)) {
272 		device_printf(dev, "could not allocate resources.\n");
273 		return (ENXIO);
274 	}
275 
276 	/* CSR memory interface */
277 	sc->bst = rman_get_bustag(sc->res[0]);
278 	sc->bsh = rman_get_bushandle(sc->res[0]);
279 
280 	/* Setup interrupt handler */
281 	err = bus_setup_intr(dev, sc->res[1], INTR_TYPE_MISC | INTR_MPSAFE,
282 	    NULL, axidma_intr_tx, sc, &sc->ih[0]);
283 	if (err) {
284 		device_printf(dev, "Unable to alloc interrupt resource.\n");
285 		return (ENXIO);
286 	}
287 
288 	/* Setup interrupt handler */
289 	err = bus_setup_intr(dev, sc->res[2], INTR_TYPE_MISC | INTR_MPSAFE,
290 	    NULL, axidma_intr_rx, sc, &sc->ih[1]);
291 	if (err) {
292 		device_printf(dev, "Unable to alloc interrupt resource.\n");
293 		return (ENXIO);
294 	}
295 
296 	node = ofw_bus_get_node(dev);
297 	xref = OF_xref_from_node(node);
298 	OF_device_register_xref(xref, dev);
299 
300 	return (0);
301 }
302 
303 static int
304 axidma_detach(device_t dev)
305 {
306 	struct axidma_softc *sc;
307 
308 	sc = device_get_softc(dev);
309 
310 	bus_teardown_intr(dev, sc->res[1], sc->ih[0]);
311 	bus_teardown_intr(dev, sc->res[2], sc->ih[1]);
312 	bus_release_resources(dev, axidma_spec, sc->res);
313 
314 	return (0);
315 }
316 
317 static int
318 axidma_desc_free(struct axidma_softc *sc, struct axidma_channel *chan)
319 {
320 	struct xdma_channel *xchan;
321 	int nsegments;
322 
323 	nsegments = chan->descs_num;
324 	xchan = chan->xchan;
325 
326 	free(chan->descs, M_DEVBUF);
327 	free(chan->descs_phys, M_DEVBUF);
328 
329 	pmap_kremove_device(chan->mem_vaddr, chan->mem_size);
330 	kva_free(chan->mem_vaddr, chan->mem_size);
331 	vmem_free(xchan->vmem, chan->mem_paddr, chan->mem_size);
332 
333 	return (0);
334 }
335 
336 static int
337 axidma_desc_alloc(struct axidma_softc *sc, struct xdma_channel *xchan,
338     uint32_t desc_size)
339 {
340 	struct axidma_channel *chan;
341 	int nsegments;
342 	int i;
343 
344 	chan = (struct axidma_channel *)xchan->chan;
345 	nsegments = chan->descs_num;
346 
347 	chan->descs = malloc(nsegments * sizeof(struct axidma_desc *),
348 	    M_DEVBUF, M_NOWAIT | M_ZERO);
349 	if (chan->descs == NULL) {
350 		device_printf(sc->dev,
351 		    "%s: Can't allocate memory.\n", __func__);
352 		return (-1);
353 	}
354 
355 	chan->descs_phys = malloc(nsegments * sizeof(bus_dma_segment_t),
356 	    M_DEVBUF, M_NOWAIT | M_ZERO);
357 	chan->mem_size = desc_size * nsegments;
358 	if (vmem_alloc(xchan->vmem, chan->mem_size, M_FIRSTFIT | M_NOWAIT,
359 	    &chan->mem_paddr)) {
360 		device_printf(sc->dev, "Failed to allocate memory.\n");
361 		return (-1);
362 	}
363 	chan->mem_vaddr = kva_alloc(chan->mem_size);
364 	pmap_kenter_device(chan->mem_vaddr, chan->mem_size, chan->mem_paddr);
365 
366 	device_printf(sc->dev, "Allocated chunk %lx %d\n",
367 	    chan->mem_paddr, chan->mem_size);
368 
369 	for (i = 0; i < nsegments; i++) {
370 		chan->descs[i] = (struct axidma_desc *)
371 		    ((uint64_t)chan->mem_vaddr + desc_size * i);
372 		chan->descs_phys[i] = chan->mem_paddr + desc_size * i;
373 	}
374 
375 	return (0);
376 }
377 
378 static int
379 axidma_channel_alloc(device_t dev, struct xdma_channel *xchan)
380 {
381 	xdma_controller_t *xdma;
382 	struct axidma_fdt_data *data;
383 	struct axidma_channel *chan;
384 	struct axidma_softc *sc;
385 
386 	sc = device_get_softc(dev);
387 
388 	if (xchan->caps & XCHAN_CAP_BUSDMA) {
389 		device_printf(sc->dev,
390 		    "Error: busdma operation is not implemented.");
391 		return (-1);
392 	}
393 
394 	xdma = xchan->xdma;
395 	data = xdma->data;
396 
397 	chan = &sc->channels[data->id];
398 	if (chan->used == false) {
399 		if (axidma_reset(sc, data->id) != 0)
400 			return (-1);
401 		chan->xchan = xchan;
402 		xchan->chan = (void *)chan;
403 		chan->sc = sc;
404 		chan->used = true;
405 		chan->idx_head = 0;
406 		chan->idx_tail = 0;
407 		chan->descs_used_count = 0;
408 		chan->descs_num = AXIDMA_DESCS_NUM;
409 
410 		return (0);
411 	}
412 
413 	return (-1);
414 }
415 
416 static int
417 axidma_channel_free(device_t dev, struct xdma_channel *xchan)
418 {
419 	struct axidma_channel *chan;
420 	struct axidma_softc *sc;
421 
422 	sc = device_get_softc(dev);
423 
424 	chan = (struct axidma_channel *)xchan->chan;
425 
426 	axidma_desc_free(sc, chan);
427 
428 	chan->used = false;
429 
430 	return (0);
431 }
432 
433 static int
434 axidma_channel_capacity(device_t dev, xdma_channel_t *xchan,
435     uint32_t *capacity)
436 {
437 	struct axidma_channel *chan;
438 	uint32_t c;
439 
440 	chan = (struct axidma_channel *)xchan->chan;
441 
442 	/* At least one descriptor must be left empty. */
443 	c = (chan->descs_num - chan->descs_used_count - 1);
444 
445 	*capacity = c;
446 
447 	return (0);
448 }
449 
450 static int
451 axidma_channel_submit_sg(device_t dev, struct xdma_channel *xchan,
452     struct xdma_sglist *sg, uint32_t sg_n)
453 {
454 	xdma_controller_t *xdma;
455 	struct axidma_fdt_data *data;
456 	struct axidma_channel *chan;
457 	struct axidma_desc *desc;
458 	struct axidma_softc *sc;
459 	uint32_t src_addr;
460 	uint32_t dst_addr;
461 	uint32_t addr;
462 	uint32_t len;
463 	uint32_t tmp;
464 	int i;
465 	int tail;
466 
467 	dprintf("%s: sg_n %d\n", __func__, sg_n);
468 
469 	sc = device_get_softc(dev);
470 
471 	chan = (struct axidma_channel *)xchan->chan;
472 	xdma = xchan->xdma;
473 	data = xdma->data;
474 
475 	if (sg_n == 0)
476 		return (0);
477 
478 	tail = chan->idx_head;
479 
480 	tmp = 0;
481 
482 	for (i = 0; i < sg_n; i++) {
483 		src_addr = (uint32_t)sg[i].src_addr;
484 		dst_addr = (uint32_t)sg[i].dst_addr;
485 		len = (uint32_t)sg[i].len;
486 
487 		dprintf("%s(%d): src %x dst %x len %d\n", __func__,
488 		    data->id, src_addr, dst_addr, len);
489 
490 		desc = chan->descs[chan->idx_head];
491 		if (sg[i].direction == XDMA_MEM_TO_DEV)
492 			desc->phys = src_addr;
493 		else
494 			desc->phys = dst_addr;
495 		desc->status = 0;
496 		desc->control = len;
497 		if (sg[i].first == 1)
498 			desc->control |= BD_CONTROL_TXSOF;
499 		if (sg[i].last == 1)
500 			desc->control |= BD_CONTROL_TXEOF;
501 
502 		tmp = chan->idx_head;
503 
504 		atomic_add_int(&chan->descs_used_count, 1);
505 		chan->idx_head = axidma_next_desc(chan, chan->idx_head);
506 	}
507 
508 	dprintf("%s(%d): _curdesc %x\n", __func__, data->id,
509 	    READ8(sc, AXI_CURDESC(data->id)));
510 	dprintf("%s(%d): _curdesc %x\n", __func__, data->id,
511 	    READ8(sc, AXI_CURDESC(data->id)));
512 	dprintf("%s(%d): status %x\n", __func__, data->id,
513 	    READ4(sc, AXI_DMASR(data->id)));
514 
515 	addr = chan->descs_phys[tmp];
516 	WRITE8(sc, AXI_TAILDESC(data->id), addr);
517 
518 	return (0);
519 }
520 
521 static int
522 axidma_channel_prep_sg(device_t dev, struct xdma_channel *xchan)
523 {
524 	xdma_controller_t *xdma;
525 	struct axidma_fdt_data *data;
526 	struct axidma_channel *chan;
527 	struct axidma_desc *desc;
528 	struct axidma_softc *sc;
529 	uint32_t addr;
530 	uint32_t reg;
531 	int ret;
532 	int i;
533 
534 	sc = device_get_softc(dev);
535 
536 	chan = (struct axidma_channel *)xchan->chan;
537 	xdma = xchan->xdma;
538 	data = xdma->data;
539 
540 	dprintf("%s(%d)\n", __func__, data->id);
541 
542 	ret = axidma_desc_alloc(sc, xchan, sizeof(struct axidma_desc));
543 	if (ret != 0) {
544 		device_printf(sc->dev,
545 		    "%s: Can't allocate descriptors.\n", __func__);
546 		return (-1);
547 	}
548 
549 	for (i = 0; i < chan->descs_num; i++) {
550 		desc = chan->descs[i];
551 		bzero(desc, sizeof(struct axidma_desc));
552 
553 		if (i == (chan->descs_num - 1))
554 			desc->next = chan->descs_phys[0];
555 		else
556 			desc->next = chan->descs_phys[i + 1];
557 		desc->status = 0;
558 		desc->control = 0;
559 
560 		dprintf("%s(%d): desc %d vaddr %lx next paddr %x\n", __func__,
561 		    data->id, i, (uint64_t)desc, le32toh(desc->next));
562 	}
563 
564 	addr = chan->descs_phys[0];
565 	WRITE8(sc, AXI_CURDESC(data->id), addr);
566 
567 	reg = READ4(sc, AXI_DMACR(data->id));
568 	reg |= DMACR_IOC_IRQEN | DMACR_DLY_IRQEN | DMACR_ERR_IRQEN;
569 	WRITE4(sc, AXI_DMACR(data->id), reg);
570 	reg |= DMACR_RS;
571 	WRITE4(sc, AXI_DMACR(data->id), reg);
572 
573 	return (0);
574 }
575 
576 static int
577 axidma_channel_control(device_t dev, xdma_channel_t *xchan, int cmd)
578 {
579 	struct axidma_channel *chan;
580 	struct axidma_softc *sc;
581 
582 	sc = device_get_softc(dev);
583 
584 	chan = (struct axidma_channel *)xchan->chan;
585 
586 	switch (cmd) {
587 	case XDMA_CMD_BEGIN:
588 	case XDMA_CMD_TERMINATE:
589 	case XDMA_CMD_PAUSE:
590 		/* TODO: implement me */
591 		return (-1);
592 	}
593 
594 	return (0);
595 }
596 
597 #ifdef FDT
598 static int
599 axidma_ofw_md_data(device_t dev, pcell_t *cells, int ncells, void **ptr)
600 {
601 	struct axidma_fdt_data *data;
602 
603 	if (ncells != 1)
604 		return (-1);
605 
606 	data = malloc(sizeof(struct axidma_fdt_data),
607 	    M_DEVBUF, (M_WAITOK | M_ZERO));
608 	data->id = cells[0];
609 
610 	*ptr = data;
611 
612 	return (0);
613 }
614 #endif
615 
616 static device_method_t axidma_methods[] = {
617 	/* Device interface */
618 	DEVMETHOD(device_probe,			axidma_probe),
619 	DEVMETHOD(device_attach,		axidma_attach),
620 	DEVMETHOD(device_detach,		axidma_detach),
621 
622 	/* xDMA Interface */
623 	DEVMETHOD(xdma_channel_alloc,		axidma_channel_alloc),
624 	DEVMETHOD(xdma_channel_free,		axidma_channel_free),
625 	DEVMETHOD(xdma_channel_control,		axidma_channel_control),
626 
627 	/* xDMA SG Interface */
628 	DEVMETHOD(xdma_channel_capacity,	axidma_channel_capacity),
629 	DEVMETHOD(xdma_channel_prep_sg,		axidma_channel_prep_sg),
630 	DEVMETHOD(xdma_channel_submit_sg,	axidma_channel_submit_sg),
631 
632 #ifdef FDT
633 	DEVMETHOD(xdma_ofw_md_data,		axidma_ofw_md_data),
634 #endif
635 
636 	DEVMETHOD_END
637 };
638 
639 static driver_t axidma_driver = {
640 	"axidma",
641 	axidma_methods,
642 	sizeof(struct axidma_softc),
643 };
644 
645 static devclass_t axidma_devclass;
646 
647 EARLY_DRIVER_MODULE(axidma, simplebus, axidma_driver, axidma_devclass, 0, 0,
648     BUS_PASS_INTERRUPT + BUS_PASS_ORDER_LATE);
649