xref: /freebsd/sys/dev/xilinx/axidma.c (revision 38a52bd3)
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	READ4(_sc, _reg)	\
65 	bus_space_read_4(_sc->bst, _sc->bsh, _reg)
66 #define	WRITE4(_sc, _reg, _val)	\
67 	bus_space_write_4(_sc->bst, _sc->bsh, _reg, _val)
68 #define	READ8(_sc, _reg)	\
69 	bus_space_read_8(_sc->bst, _sc->bsh, _reg)
70 #define	WRITE8(_sc, _reg, _val)	\
71 	bus_space_write_8(_sc->bst, _sc->bsh, _reg, _val)
72 
73 #define AXIDMA_DEBUG
74 #undef AXIDMA_DEBUG
75 
76 #ifdef AXIDMA_DEBUG
77 #define dprintf(fmt, ...)  printf(fmt, ##__VA_ARGS__)
78 #else
79 #define dprintf(fmt, ...)
80 #endif
81 
82 extern struct bus_space memmap_bus;
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 
322 	xchan = chan->xchan;
323 
324 	free(chan->descs, M_DEVBUF);
325 	free(chan->descs_phys, M_DEVBUF);
326 
327 	pmap_kremove_device(chan->mem_vaddr, chan->mem_size);
328 	kva_free(chan->mem_vaddr, chan->mem_size);
329 	vmem_free(xchan->vmem, chan->mem_paddr, chan->mem_size);
330 
331 	return (0);
332 }
333 
334 static int
335 axidma_desc_alloc(struct axidma_softc *sc, struct xdma_channel *xchan,
336     uint32_t desc_size)
337 {
338 	struct axidma_channel *chan;
339 	int nsegments;
340 	int i;
341 
342 	chan = (struct axidma_channel *)xchan->chan;
343 	nsegments = chan->descs_num;
344 
345 	chan->descs = malloc(nsegments * sizeof(struct axidma_desc *),
346 	    M_DEVBUF, M_NOWAIT | M_ZERO);
347 	if (chan->descs == NULL) {
348 		device_printf(sc->dev,
349 		    "%s: Can't allocate memory.\n", __func__);
350 		return (-1);
351 	}
352 
353 	chan->descs_phys = malloc(nsegments * sizeof(bus_dma_segment_t),
354 	    M_DEVBUF, M_NOWAIT | M_ZERO);
355 	chan->mem_size = desc_size * nsegments;
356 	if (vmem_alloc(xchan->vmem, chan->mem_size, M_FIRSTFIT | M_NOWAIT,
357 	    &chan->mem_paddr)) {
358 		device_printf(sc->dev, "Failed to allocate memory.\n");
359 		return (-1);
360 	}
361 	chan->mem_vaddr = kva_alloc(chan->mem_size);
362 	pmap_kenter_device(chan->mem_vaddr, chan->mem_size, chan->mem_paddr);
363 
364 	device_printf(sc->dev, "Allocated chunk %lx %lu\n",
365 	    chan->mem_paddr, chan->mem_size);
366 
367 	for (i = 0; i < nsegments; i++) {
368 		chan->descs[i] = (struct axidma_desc *)
369 		    ((uint64_t)chan->mem_vaddr + desc_size * i);
370 		chan->descs_phys[i] = chan->mem_paddr + desc_size * i;
371 	}
372 
373 	return (0);
374 }
375 
376 static int
377 axidma_channel_alloc(device_t dev, struct xdma_channel *xchan)
378 {
379 	xdma_controller_t *xdma;
380 	struct axidma_fdt_data *data;
381 	struct axidma_channel *chan;
382 	struct axidma_softc *sc;
383 
384 	sc = device_get_softc(dev);
385 
386 	if (xchan->caps & XCHAN_CAP_BUSDMA) {
387 		device_printf(sc->dev,
388 		    "Error: busdma operation is not implemented.");
389 		return (-1);
390 	}
391 
392 	xdma = xchan->xdma;
393 	data = xdma->data;
394 
395 	chan = &sc->channels[data->id];
396 	if (chan->used == false) {
397 		if (axidma_reset(sc, data->id) != 0)
398 			return (-1);
399 		chan->xchan = xchan;
400 		xchan->caps |= XCHAN_CAP_BOUNCE;
401 		xchan->chan = (void *)chan;
402 		chan->sc = sc;
403 		chan->used = true;
404 		chan->idx_head = 0;
405 		chan->idx_tail = 0;
406 		chan->descs_used_count = 0;
407 		chan->descs_num = AXIDMA_DESCS_NUM;
408 
409 		return (0);
410 	}
411 
412 	return (-1);
413 }
414 
415 static int
416 axidma_channel_free(device_t dev, struct xdma_channel *xchan)
417 {
418 	struct axidma_channel *chan;
419 	struct axidma_softc *sc;
420 
421 	sc = device_get_softc(dev);
422 
423 	chan = (struct axidma_channel *)xchan->chan;
424 
425 	axidma_desc_free(sc, chan);
426 
427 	chan->used = false;
428 
429 	return (0);
430 }
431 
432 static int
433 axidma_channel_capacity(device_t dev, xdma_channel_t *xchan,
434     uint32_t *capacity)
435 {
436 	struct axidma_channel *chan;
437 	uint32_t c;
438 
439 	chan = (struct axidma_channel *)xchan->chan;
440 
441 	/* At least one descriptor must be left empty. */
442 	c = (chan->descs_num - chan->descs_used_count - 1);
443 
444 	*capacity = c;
445 
446 	return (0);
447 }
448 
449 static int
450 axidma_channel_submit_sg(device_t dev, struct xdma_channel *xchan,
451     struct xdma_sglist *sg, uint32_t sg_n)
452 {
453 	xdma_controller_t *xdma;
454 	struct axidma_fdt_data *data;
455 	struct axidma_channel *chan;
456 	struct axidma_desc *desc;
457 	struct axidma_softc *sc;
458 	uint32_t src_addr;
459 	uint32_t dst_addr;
460 	uint32_t addr;
461 	uint32_t len;
462 	uint32_t tmp;
463 	int i;
464 
465 	dprintf("%s: sg_n %d\n", __func__, sg_n);
466 
467 	sc = device_get_softc(dev);
468 
469 	chan = (struct axidma_channel *)xchan->chan;
470 	xdma = xchan->xdma;
471 	data = xdma->data;
472 
473 	if (sg_n == 0)
474 		return (0);
475 
476 	tmp = 0;
477 
478 	for (i = 0; i < sg_n; i++) {
479 		src_addr = (uint32_t)sg[i].src_addr;
480 		dst_addr = (uint32_t)sg[i].dst_addr;
481 		len = (uint32_t)sg[i].len;
482 
483 		dprintf("%s(%d): src %x dst %x len %d\n", __func__,
484 		    data->id, src_addr, dst_addr, len);
485 
486 		desc = chan->descs[chan->idx_head];
487 		if (sg[i].direction == XDMA_MEM_TO_DEV)
488 			desc->phys = src_addr;
489 		else
490 			desc->phys = dst_addr;
491 		desc->status = 0;
492 		desc->control = len;
493 		if (sg[i].first == 1)
494 			desc->control |= BD_CONTROL_TXSOF;
495 		if (sg[i].last == 1)
496 			desc->control |= BD_CONTROL_TXEOF;
497 
498 		tmp = chan->idx_head;
499 
500 		atomic_add_int(&chan->descs_used_count, 1);
501 		chan->idx_head = axidma_next_desc(chan, chan->idx_head);
502 	}
503 
504 	dprintf("%s(%d): _curdesc %x\n", __func__, data->id,
505 	    READ8(sc, AXI_CURDESC(data->id)));
506 	dprintf("%s(%d): _curdesc %x\n", __func__, data->id,
507 	    READ8(sc, AXI_CURDESC(data->id)));
508 	dprintf("%s(%d): status %x\n", __func__, data->id,
509 	    READ4(sc, AXI_DMASR(data->id)));
510 
511 	addr = chan->descs_phys[tmp];
512 	WRITE8(sc, AXI_TAILDESC(data->id), addr);
513 
514 	return (0);
515 }
516 
517 static int
518 axidma_channel_prep_sg(device_t dev, struct xdma_channel *xchan)
519 {
520 	xdma_controller_t *xdma;
521 	struct axidma_fdt_data *data;
522 	struct axidma_channel *chan;
523 	struct axidma_desc *desc;
524 	struct axidma_softc *sc;
525 	uint32_t addr;
526 	uint32_t reg;
527 	int ret;
528 	int i;
529 
530 	sc = device_get_softc(dev);
531 
532 	chan = (struct axidma_channel *)xchan->chan;
533 	xdma = xchan->xdma;
534 	data = xdma->data;
535 
536 	dprintf("%s(%d)\n", __func__, data->id);
537 
538 	ret = axidma_desc_alloc(sc, xchan, sizeof(struct axidma_desc));
539 	if (ret != 0) {
540 		device_printf(sc->dev,
541 		    "%s: Can't allocate descriptors.\n", __func__);
542 		return (-1);
543 	}
544 
545 	for (i = 0; i < chan->descs_num; i++) {
546 		desc = chan->descs[i];
547 		bzero(desc, sizeof(struct axidma_desc));
548 
549 		if (i == (chan->descs_num - 1))
550 			desc->next = chan->descs_phys[0];
551 		else
552 			desc->next = chan->descs_phys[i + 1];
553 		desc->status = 0;
554 		desc->control = 0;
555 
556 		dprintf("%s(%d): desc %d vaddr %lx next paddr %x\n", __func__,
557 		    data->id, i, (uint64_t)desc, le32toh(desc->next));
558 	}
559 
560 	addr = chan->descs_phys[0];
561 	WRITE8(sc, AXI_CURDESC(data->id), addr);
562 
563 	reg = READ4(sc, AXI_DMACR(data->id));
564 	reg |= DMACR_IOC_IRQEN | DMACR_DLY_IRQEN | DMACR_ERR_IRQEN;
565 	WRITE4(sc, AXI_DMACR(data->id), reg);
566 	reg |= DMACR_RS;
567 	WRITE4(sc, AXI_DMACR(data->id), reg);
568 
569 	return (0);
570 }
571 
572 static int
573 axidma_channel_control(device_t dev, xdma_channel_t *xchan, int cmd)
574 {
575 
576 	switch (cmd) {
577 	case XDMA_CMD_BEGIN:
578 	case XDMA_CMD_TERMINATE:
579 	case XDMA_CMD_PAUSE:
580 		/* TODO: implement me */
581 		return (-1);
582 	}
583 
584 	return (0);
585 }
586 
587 #ifdef FDT
588 static int
589 axidma_ofw_md_data(device_t dev, pcell_t *cells, int ncells, void **ptr)
590 {
591 	struct axidma_fdt_data *data;
592 
593 	if (ncells != 1)
594 		return (-1);
595 
596 	data = malloc(sizeof(struct axidma_fdt_data),
597 	    M_DEVBUF, (M_WAITOK | M_ZERO));
598 	data->id = cells[0];
599 
600 	*ptr = data;
601 
602 	return (0);
603 }
604 #endif
605 
606 static device_method_t axidma_methods[] = {
607 	/* Device interface */
608 	DEVMETHOD(device_probe,			axidma_probe),
609 	DEVMETHOD(device_attach,		axidma_attach),
610 	DEVMETHOD(device_detach,		axidma_detach),
611 
612 	/* xDMA Interface */
613 	DEVMETHOD(xdma_channel_alloc,		axidma_channel_alloc),
614 	DEVMETHOD(xdma_channel_free,		axidma_channel_free),
615 	DEVMETHOD(xdma_channel_control,		axidma_channel_control),
616 
617 	/* xDMA SG Interface */
618 	DEVMETHOD(xdma_channel_capacity,	axidma_channel_capacity),
619 	DEVMETHOD(xdma_channel_prep_sg,		axidma_channel_prep_sg),
620 	DEVMETHOD(xdma_channel_submit_sg,	axidma_channel_submit_sg),
621 
622 #ifdef FDT
623 	DEVMETHOD(xdma_ofw_md_data,		axidma_ofw_md_data),
624 #endif
625 
626 	DEVMETHOD_END
627 };
628 
629 static driver_t axidma_driver = {
630 	"axidma",
631 	axidma_methods,
632 	sizeof(struct axidma_softc),
633 };
634 
635 EARLY_DRIVER_MODULE(axidma, simplebus, axidma_driver, 0, 0,
636     BUS_PASS_INTERRUPT + BUS_PASS_ORDER_LATE);
637