xref: /freebsd/sys/dev/xilinx/axidma.c (revision 2e3507c25e42292b45a5482e116d278f5515d04d)
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 #include "opt_platform.h"
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/conf.h>
40 #include <sys/bus.h>
41 #include <sys/kernel.h>
42 #include <sys/module.h>
43 #include <sys/rman.h>
44 
45 #include <machine/bus.h>
46 
47 #include <vm/vm.h>
48 #include <vm/vm_extern.h>
49 #include <vm/vm_page.h>
50 
51 #ifdef FDT
52 #include <dev/fdt/fdt_common.h>
53 #include <dev/ofw/ofw_bus.h>
54 #include <dev/ofw/ofw_bus_subr.h>
55 #endif
56 
57 #include <dev/xdma/xdma.h>
58 #include <dev/xilinx/axidma.h>
59 
60 #include "xdma_if.h"
61 
62 #define	READ4(_sc, _reg)	\
63 	bus_space_read_4(_sc->bst, _sc->bsh, _reg)
64 #define	WRITE4(_sc, _reg, _val)	\
65 	bus_space_write_4(_sc->bst, _sc->bsh, _reg, _val)
66 #define	READ8(_sc, _reg)	\
67 	bus_space_read_8(_sc->bst, _sc->bsh, _reg)
68 #define	WRITE8(_sc, _reg, _val)	\
69 	bus_space_write_8(_sc->bst, _sc->bsh, _reg, _val)
70 
71 #define AXIDMA_DEBUG
72 #undef AXIDMA_DEBUG
73 
74 #ifdef AXIDMA_DEBUG
75 #define dprintf(fmt, ...)  printf(fmt, ##__VA_ARGS__)
76 #else
77 #define dprintf(fmt, ...)
78 #endif
79 
80 extern struct bus_space memmap_bus;
81 
82 struct axidma_channel {
83 	struct axidma_softc	*sc;
84 	xdma_channel_t		*xchan;
85 	bool			used;
86 	int			idx_head;
87 	int			idx_tail;
88 
89 	struct axidma_desc	**descs;
90 	vm_paddr_t		*descs_phys;
91 	uint32_t		descs_num;
92 
93 	vm_size_t		mem_size;
94 	vm_offset_t		mem_paddr;
95 	vm_offset_t		mem_vaddr;
96 
97 	uint32_t		descs_used_count;
98 };
99 
100 struct axidma_softc {
101 	device_t		dev;
102 	struct resource		*res[3];
103 	bus_space_tag_t		bst;
104 	bus_space_handle_t	bsh;
105 	void			*ih[2];
106 	struct axidma_desc	desc;
107 	struct axidma_channel	channels[AXIDMA_NCHANNELS];
108 };
109 
110 static struct resource_spec axidma_spec[] = {
111 	{ SYS_RES_MEMORY,	0,	RF_ACTIVE },
112 	{ SYS_RES_IRQ,		0,	RF_ACTIVE },
113 	{ SYS_RES_IRQ,		1,	RF_ACTIVE },
114 	{ -1, 0 }
115 };
116 
117 #define	HWTYPE_NONE	0
118 #define	HWTYPE_STD	1
119 
120 static struct ofw_compat_data compat_data[] = {
121 	{ "xlnx,eth-dma",	HWTYPE_STD },
122 	{ NULL,			HWTYPE_NONE },
123 };
124 
125 static int axidma_probe(device_t dev);
126 static int axidma_attach(device_t dev);
127 static int axidma_detach(device_t dev);
128 
129 static inline uint32_t
130 axidma_next_desc(struct axidma_channel *chan, uint32_t curidx)
131 {
132 
133 	return ((curidx + 1) % chan->descs_num);
134 }
135 
136 static void
137 axidma_intr(struct axidma_softc *sc,
138     struct axidma_channel *chan)
139 {
140 	xdma_transfer_status_t status;
141 	xdma_transfer_status_t st;
142 	struct axidma_fdt_data *data;
143 	xdma_controller_t *xdma;
144 	struct axidma_desc *desc;
145 	struct xdma_channel *xchan;
146 	uint32_t tot_copied;
147 	int pending;
148 	int errors;
149 
150 	xchan = chan->xchan;
151 	xdma = xchan->xdma;
152 	data = xdma->data;
153 
154 	pending = READ4(sc, AXI_DMASR(data->id));
155 	WRITE4(sc, AXI_DMASR(data->id), pending);
156 
157 	errors = (pending & (DMASR_DMAINTERR | DMASR_DMASLVERR
158 			| DMASR_DMADECOREERR | DMASR_SGINTERR
159 			| DMASR_SGSLVERR | DMASR_SGDECERR));
160 
161 	dprintf("%s: AXI_DMASR %x\n", __func__,
162 	    READ4(sc, AXI_DMASR(data->id)));
163 	dprintf("%s: AXI_CURDESC %x\n", __func__,
164 	    READ4(sc, AXI_CURDESC(data->id)));
165 	dprintf("%s: AXI_TAILDESC %x\n", __func__,
166 	    READ4(sc, AXI_TAILDESC(data->id)));
167 
168 	tot_copied = 0;
169 
170 	while (chan->idx_tail != chan->idx_head) {
171 		desc = chan->descs[chan->idx_tail];
172 		if ((desc->status & BD_STATUS_CMPLT) == 0)
173 			break;
174 
175 		st.error = errors;
176 		st.transferred = desc->status & BD_CONTROL_LEN_M;
177 		tot_copied += st.transferred;
178 		xchan_seg_done(xchan, &st);
179 
180 		chan->idx_tail = axidma_next_desc(chan, chan->idx_tail);
181 		atomic_subtract_int(&chan->descs_used_count, 1);
182 	}
183 
184 	/* Finish operation */
185 	status.error = errors;
186 	status.transferred = tot_copied;
187 	xdma_callback(chan->xchan, &status);
188 }
189 
190 static void
191 axidma_intr_rx(void *arg)
192 {
193 	struct axidma_softc *sc;
194 	struct axidma_channel *chan;
195 
196 	dprintf("%s\n", __func__);
197 
198 	sc = arg;
199 	chan = &sc->channels[AXIDMA_RX_CHAN];
200 
201 	axidma_intr(sc, chan);
202 }
203 
204 static void
205 axidma_intr_tx(void *arg)
206 {
207 	struct axidma_softc *sc;
208 	struct axidma_channel *chan;
209 
210 	dprintf("%s\n", __func__);
211 
212 	sc = arg;
213 	chan = &sc->channels[AXIDMA_TX_CHAN];
214 
215 	axidma_intr(sc, chan);
216 }
217 
218 static int
219 axidma_reset(struct axidma_softc *sc, int chan_id)
220 {
221 	int timeout;
222 
223 	WRITE4(sc, AXI_DMACR(chan_id), DMACR_RESET);
224 
225 	timeout = 100;
226 	do {
227 		if ((READ4(sc, AXI_DMACR(chan_id)) & DMACR_RESET) == 0)
228 			break;
229 	} while (timeout--);
230 
231 	dprintf("timeout %d\n", timeout);
232 
233 	if (timeout == 0)
234 		return (-1);
235 
236 	dprintf("%s: read control after reset: %x\n",
237 	    __func__, READ4(sc, AXI_DMACR(chan_id)));
238 
239 	return (0);
240 }
241 
242 static int
243 axidma_probe(device_t dev)
244 {
245 	int hwtype;
246 
247 	if (!ofw_bus_status_okay(dev))
248 		return (ENXIO);
249 
250 	hwtype = ofw_bus_search_compatible(dev, compat_data)->ocd_data;
251 	if (hwtype == HWTYPE_NONE)
252 		return (ENXIO);
253 
254 	device_set_desc(dev, "Xilinx AXI DMA");
255 
256 	return (BUS_PROBE_DEFAULT);
257 }
258 
259 static int
260 axidma_attach(device_t dev)
261 {
262 	struct axidma_softc *sc;
263 	phandle_t xref, node;
264 	int err;
265 
266 	sc = device_get_softc(dev);
267 	sc->dev = dev;
268 
269 	if (bus_alloc_resources(dev, axidma_spec, sc->res)) {
270 		device_printf(dev, "could not allocate resources.\n");
271 		return (ENXIO);
272 	}
273 
274 	/* CSR memory interface */
275 	sc->bst = rman_get_bustag(sc->res[0]);
276 	sc->bsh = rman_get_bushandle(sc->res[0]);
277 
278 	/* Setup interrupt handler */
279 	err = bus_setup_intr(dev, sc->res[1], INTR_TYPE_MISC | INTR_MPSAFE,
280 	    NULL, axidma_intr_tx, sc, &sc->ih[0]);
281 	if (err) {
282 		device_printf(dev, "Unable to alloc interrupt resource.\n");
283 		return (ENXIO);
284 	}
285 
286 	/* Setup interrupt handler */
287 	err = bus_setup_intr(dev, sc->res[2], INTR_TYPE_MISC | INTR_MPSAFE,
288 	    NULL, axidma_intr_rx, sc, &sc->ih[1]);
289 	if (err) {
290 		device_printf(dev, "Unable to alloc interrupt resource.\n");
291 		return (ENXIO);
292 	}
293 
294 	node = ofw_bus_get_node(dev);
295 	xref = OF_xref_from_node(node);
296 	OF_device_register_xref(xref, dev);
297 
298 	return (0);
299 }
300 
301 static int
302 axidma_detach(device_t dev)
303 {
304 	struct axidma_softc *sc;
305 
306 	sc = device_get_softc(dev);
307 
308 	bus_teardown_intr(dev, sc->res[1], sc->ih[0]);
309 	bus_teardown_intr(dev, sc->res[2], sc->ih[1]);
310 	bus_release_resources(dev, axidma_spec, sc->res);
311 
312 	return (0);
313 }
314 
315 static int
316 axidma_desc_free(struct axidma_softc *sc, struct axidma_channel *chan)
317 {
318 	struct xdma_channel *xchan;
319 
320 	xchan = chan->xchan;
321 
322 	free(chan->descs, M_DEVBUF);
323 	free(chan->descs_phys, M_DEVBUF);
324 
325 	pmap_kremove_device(chan->mem_vaddr, chan->mem_size);
326 	kva_free(chan->mem_vaddr, chan->mem_size);
327 	vmem_free(xchan->vmem, chan->mem_paddr, chan->mem_size);
328 
329 	return (0);
330 }
331 
332 static int
333 axidma_desc_alloc(struct axidma_softc *sc, struct xdma_channel *xchan,
334     uint32_t desc_size)
335 {
336 	struct axidma_channel *chan;
337 	int nsegments;
338 	int i;
339 
340 	chan = (struct axidma_channel *)xchan->chan;
341 	nsegments = chan->descs_num;
342 
343 	chan->descs = malloc(nsegments * sizeof(struct axidma_desc *),
344 	    M_DEVBUF, M_NOWAIT | M_ZERO);
345 	if (chan->descs == NULL) {
346 		device_printf(sc->dev,
347 		    "%s: Can't allocate memory.\n", __func__);
348 		return (-1);
349 	}
350 
351 	chan->descs_phys = malloc(nsegments * sizeof(bus_dma_segment_t),
352 	    M_DEVBUF, M_NOWAIT | M_ZERO);
353 	chan->mem_size = desc_size * nsegments;
354 	if (vmem_alloc(xchan->vmem, chan->mem_size, M_FIRSTFIT | M_NOWAIT,
355 	    &chan->mem_paddr)) {
356 		device_printf(sc->dev, "Failed to allocate memory.\n");
357 		return (-1);
358 	}
359 	chan->mem_vaddr = kva_alloc(chan->mem_size);
360 	pmap_kenter_device(chan->mem_vaddr, chan->mem_size, chan->mem_paddr);
361 
362 	device_printf(sc->dev, "Allocated chunk %lx %lu\n",
363 	    chan->mem_paddr, chan->mem_size);
364 
365 	for (i = 0; i < nsegments; i++) {
366 		chan->descs[i] = (struct axidma_desc *)
367 		    ((uint64_t)chan->mem_vaddr + desc_size * i);
368 		chan->descs_phys[i] = chan->mem_paddr + desc_size * i;
369 	}
370 
371 	return (0);
372 }
373 
374 static int
375 axidma_channel_alloc(device_t dev, struct xdma_channel *xchan)
376 {
377 	xdma_controller_t *xdma;
378 	struct axidma_fdt_data *data;
379 	struct axidma_channel *chan;
380 	struct axidma_softc *sc;
381 
382 	sc = device_get_softc(dev);
383 
384 	if (xchan->caps & XCHAN_CAP_BUSDMA) {
385 		device_printf(sc->dev,
386 		    "Error: busdma operation is not implemented.");
387 		return (-1);
388 	}
389 
390 	xdma = xchan->xdma;
391 	data = xdma->data;
392 
393 	chan = &sc->channels[data->id];
394 	if (chan->used == false) {
395 		if (axidma_reset(sc, data->id) != 0)
396 			return (-1);
397 		chan->xchan = xchan;
398 		xchan->caps |= XCHAN_CAP_BOUNCE;
399 		xchan->chan = (void *)chan;
400 		chan->sc = sc;
401 		chan->used = true;
402 		chan->idx_head = 0;
403 		chan->idx_tail = 0;
404 		chan->descs_used_count = 0;
405 		chan->descs_num = AXIDMA_DESCS_NUM;
406 
407 		return (0);
408 	}
409 
410 	return (-1);
411 }
412 
413 static int
414 axidma_channel_free(device_t dev, struct xdma_channel *xchan)
415 {
416 	struct axidma_channel *chan;
417 	struct axidma_softc *sc;
418 
419 	sc = device_get_softc(dev);
420 
421 	chan = (struct axidma_channel *)xchan->chan;
422 
423 	axidma_desc_free(sc, chan);
424 
425 	chan->used = false;
426 
427 	return (0);
428 }
429 
430 static int
431 axidma_channel_capacity(device_t dev, xdma_channel_t *xchan,
432     uint32_t *capacity)
433 {
434 	struct axidma_channel *chan;
435 	uint32_t c;
436 
437 	chan = (struct axidma_channel *)xchan->chan;
438 
439 	/* At least one descriptor must be left empty. */
440 	c = (chan->descs_num - chan->descs_used_count - 1);
441 
442 	*capacity = c;
443 
444 	return (0);
445 }
446 
447 static int
448 axidma_channel_submit_sg(device_t dev, struct xdma_channel *xchan,
449     struct xdma_sglist *sg, uint32_t sg_n)
450 {
451 	xdma_controller_t *xdma;
452 	struct axidma_fdt_data *data;
453 	struct axidma_channel *chan;
454 	struct axidma_desc *desc;
455 	struct axidma_softc *sc;
456 	uint32_t src_addr;
457 	uint32_t dst_addr;
458 	uint32_t addr;
459 	uint32_t len;
460 	uint32_t tmp;
461 	int i;
462 
463 	dprintf("%s: sg_n %d\n", __func__, sg_n);
464 
465 	sc = device_get_softc(dev);
466 
467 	chan = (struct axidma_channel *)xchan->chan;
468 	xdma = xchan->xdma;
469 	data = xdma->data;
470 
471 	if (sg_n == 0)
472 		return (0);
473 
474 	tmp = 0;
475 
476 	for (i = 0; i < sg_n; i++) {
477 		src_addr = (uint32_t)sg[i].src_addr;
478 		dst_addr = (uint32_t)sg[i].dst_addr;
479 		len = (uint32_t)sg[i].len;
480 
481 		dprintf("%s(%d): src %x dst %x len %d\n", __func__,
482 		    data->id, src_addr, dst_addr, len);
483 
484 		desc = chan->descs[chan->idx_head];
485 		if (sg[i].direction == XDMA_MEM_TO_DEV)
486 			desc->phys = src_addr;
487 		else
488 			desc->phys = dst_addr;
489 		desc->status = 0;
490 		desc->control = len;
491 		if (sg[i].first == 1)
492 			desc->control |= BD_CONTROL_TXSOF;
493 		if (sg[i].last == 1)
494 			desc->control |= BD_CONTROL_TXEOF;
495 
496 		tmp = chan->idx_head;
497 
498 		atomic_add_int(&chan->descs_used_count, 1);
499 		chan->idx_head = axidma_next_desc(chan, chan->idx_head);
500 	}
501 
502 	dprintf("%s(%d): _curdesc %x\n", __func__, data->id,
503 	    READ8(sc, AXI_CURDESC(data->id)));
504 	dprintf("%s(%d): _curdesc %x\n", __func__, data->id,
505 	    READ8(sc, AXI_CURDESC(data->id)));
506 	dprintf("%s(%d): status %x\n", __func__, data->id,
507 	    READ4(sc, AXI_DMASR(data->id)));
508 
509 	addr = chan->descs_phys[tmp];
510 	WRITE8(sc, AXI_TAILDESC(data->id), addr);
511 
512 	return (0);
513 }
514 
515 static int
516 axidma_channel_prep_sg(device_t dev, struct xdma_channel *xchan)
517 {
518 	xdma_controller_t *xdma;
519 	struct axidma_fdt_data *data;
520 	struct axidma_channel *chan;
521 	struct axidma_desc *desc;
522 	struct axidma_softc *sc;
523 	uint32_t addr;
524 	uint32_t reg;
525 	int ret;
526 	int i;
527 
528 	sc = device_get_softc(dev);
529 
530 	chan = (struct axidma_channel *)xchan->chan;
531 	xdma = xchan->xdma;
532 	data = xdma->data;
533 
534 	dprintf("%s(%d)\n", __func__, data->id);
535 
536 	ret = axidma_desc_alloc(sc, xchan, sizeof(struct axidma_desc));
537 	if (ret != 0) {
538 		device_printf(sc->dev,
539 		    "%s: Can't allocate descriptors.\n", __func__);
540 		return (-1);
541 	}
542 
543 	for (i = 0; i < chan->descs_num; i++) {
544 		desc = chan->descs[i];
545 		bzero(desc, sizeof(struct axidma_desc));
546 
547 		if (i == (chan->descs_num - 1))
548 			desc->next = chan->descs_phys[0];
549 		else
550 			desc->next = chan->descs_phys[i + 1];
551 		desc->status = 0;
552 		desc->control = 0;
553 
554 		dprintf("%s(%d): desc %d vaddr %lx next paddr %x\n", __func__,
555 		    data->id, i, (uint64_t)desc, le32toh(desc->next));
556 	}
557 
558 	addr = chan->descs_phys[0];
559 	WRITE8(sc, AXI_CURDESC(data->id), addr);
560 
561 	reg = READ4(sc, AXI_DMACR(data->id));
562 	reg |= DMACR_IOC_IRQEN | DMACR_DLY_IRQEN | DMACR_ERR_IRQEN;
563 	WRITE4(sc, AXI_DMACR(data->id), reg);
564 	reg |= DMACR_RS;
565 	WRITE4(sc, AXI_DMACR(data->id), reg);
566 
567 	return (0);
568 }
569 
570 static int
571 axidma_channel_control(device_t dev, xdma_channel_t *xchan, int cmd)
572 {
573 
574 	switch (cmd) {
575 	case XDMA_CMD_BEGIN:
576 	case XDMA_CMD_TERMINATE:
577 	case XDMA_CMD_PAUSE:
578 		/* TODO: implement me */
579 		return (-1);
580 	}
581 
582 	return (0);
583 }
584 
585 #ifdef FDT
586 static int
587 axidma_ofw_md_data(device_t dev, pcell_t *cells, int ncells, void **ptr)
588 {
589 	struct axidma_fdt_data *data;
590 
591 	if (ncells != 1)
592 		return (-1);
593 
594 	data = malloc(sizeof(struct axidma_fdt_data),
595 	    M_DEVBUF, (M_WAITOK | M_ZERO));
596 	data->id = cells[0];
597 
598 	*ptr = data;
599 
600 	return (0);
601 }
602 #endif
603 
604 static device_method_t axidma_methods[] = {
605 	/* Device interface */
606 	DEVMETHOD(device_probe,			axidma_probe),
607 	DEVMETHOD(device_attach,		axidma_attach),
608 	DEVMETHOD(device_detach,		axidma_detach),
609 
610 	/* xDMA Interface */
611 	DEVMETHOD(xdma_channel_alloc,		axidma_channel_alloc),
612 	DEVMETHOD(xdma_channel_free,		axidma_channel_free),
613 	DEVMETHOD(xdma_channel_control,		axidma_channel_control),
614 
615 	/* xDMA SG Interface */
616 	DEVMETHOD(xdma_channel_capacity,	axidma_channel_capacity),
617 	DEVMETHOD(xdma_channel_prep_sg,		axidma_channel_prep_sg),
618 	DEVMETHOD(xdma_channel_submit_sg,	axidma_channel_submit_sg),
619 
620 #ifdef FDT
621 	DEVMETHOD(xdma_ofw_md_data,		axidma_ofw_md_data),
622 #endif
623 
624 	DEVMETHOD_END
625 };
626 
627 static driver_t axidma_driver = {
628 	"axidma",
629 	axidma_methods,
630 	sizeof(struct axidma_softc),
631 };
632 
633 EARLY_DRIVER_MODULE(axidma, simplebus, axidma_driver, 0, 0,
634     BUS_PASS_INTERRUPT + BUS_PASS_ORDER_LATE);
635