xref: /freebsd/sys/dev/xilinx/axidma.c (revision b670c9bafc0e31c7609969bf374b2e80bdc00211)
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 		cpu_dcache_wbinv_range((vm_offset_t)desc,
173 		    sizeof(struct axidma_desc));
174 
175 		if ((desc->status & BD_STATUS_CMPLT) == 0)
176 			break;
177 
178 		st.error = errors;
179 		st.transferred = desc->status & BD_CONTROL_LEN_M;
180 		tot_copied += st.transferred;
181 		xchan_seg_done(xchan, &st);
182 
183 		chan->idx_tail = axidma_next_desc(chan, chan->idx_tail);
184 		atomic_subtract_int(&chan->descs_used_count, 1);
185 	}
186 
187 	/* Finish operation */
188 	status.error = errors;
189 	status.transferred = tot_copied;
190 	xdma_callback(chan->xchan, &status);
191 }
192 
193 static void
194 axidma_intr_rx(void *arg)
195 {
196 	struct axidma_softc *sc;
197 	struct axidma_channel *chan;
198 
199 	dprintf("%s\n", __func__);
200 
201 	sc = arg;
202 	chan = &sc->channels[AXIDMA_RX_CHAN];
203 
204 	axidma_intr(sc, chan);
205 }
206 
207 static void
208 axidma_intr_tx(void *arg)
209 {
210 	struct axidma_softc *sc;
211 	struct axidma_channel *chan;
212 
213 	dprintf("%s\n", __func__);
214 
215 	sc = arg;
216 	chan = &sc->channels[AXIDMA_TX_CHAN];
217 
218 	axidma_intr(sc, chan);
219 }
220 
221 static int
222 axidma_reset(struct axidma_softc *sc, int chan_id)
223 {
224 	int timeout;
225 
226 	WRITE4(sc, AXI_DMACR(chan_id), DMACR_RESET);
227 
228 	timeout = 100;
229 	do {
230 		if ((READ4(sc, AXI_DMACR(chan_id)) & DMACR_RESET) == 0)
231 			break;
232 	} while (timeout--);
233 
234 	dprintf("timeout %d\n", timeout);
235 
236 	if (timeout == 0)
237 		return (-1);
238 
239 	dprintf("%s: read control after reset: %x\n",
240 	    __func__, READ4(sc, AXI_DMACR(chan_id)));
241 
242 	return (0);
243 }
244 
245 static int
246 axidma_probe(device_t dev)
247 {
248 	int hwtype;
249 
250 	if (!ofw_bus_status_okay(dev))
251 		return (ENXIO);
252 
253 	hwtype = ofw_bus_search_compatible(dev, compat_data)->ocd_data;
254 	if (hwtype == HWTYPE_NONE)
255 		return (ENXIO);
256 
257 	device_set_desc(dev, "Xilinx AXI DMA");
258 
259 	return (BUS_PROBE_DEFAULT);
260 }
261 
262 static int
263 axidma_attach(device_t dev)
264 {
265 	struct axidma_softc *sc;
266 	phandle_t xref, node;
267 	int err;
268 
269 	sc = device_get_softc(dev);
270 	sc->dev = dev;
271 
272 	if (bus_alloc_resources(dev, axidma_spec, sc->res)) {
273 		device_printf(dev, "could not allocate resources.\n");
274 		return (ENXIO);
275 	}
276 
277 	/* CSR memory interface */
278 	sc->bst = rman_get_bustag(sc->res[0]);
279 	sc->bsh = rman_get_bushandle(sc->res[0]);
280 
281 	/* Setup interrupt handler */
282 	err = bus_setup_intr(dev, sc->res[1], INTR_TYPE_MISC | INTR_MPSAFE,
283 	    NULL, axidma_intr_tx, sc, &sc->ih[0]);
284 	if (err) {
285 		device_printf(dev, "Unable to alloc interrupt resource.\n");
286 		return (ENXIO);
287 	}
288 
289 	/* Setup interrupt handler */
290 	err = bus_setup_intr(dev, sc->res[2], INTR_TYPE_MISC | INTR_MPSAFE,
291 	    NULL, axidma_intr_rx, sc, &sc->ih[1]);
292 	if (err) {
293 		device_printf(dev, "Unable to alloc interrupt resource.\n");
294 		return (ENXIO);
295 	}
296 
297 	node = ofw_bus_get_node(dev);
298 	xref = OF_xref_from_node(node);
299 	OF_device_register_xref(xref, dev);
300 
301 	return (0);
302 }
303 
304 static int
305 axidma_detach(device_t dev)
306 {
307 	struct axidma_softc *sc;
308 
309 	sc = device_get_softc(dev);
310 
311 	bus_teardown_intr(dev, sc->res[1], sc->ih[0]);
312 	bus_teardown_intr(dev, sc->res[2], sc->ih[1]);
313 	bus_release_resources(dev, axidma_spec, sc->res);
314 
315 	return (0);
316 }
317 
318 static int
319 axidma_desc_free(struct axidma_softc *sc, struct axidma_channel *chan)
320 {
321 	struct xdma_channel *xchan;
322 
323 	xchan = chan->xchan;
324 
325 	free(chan->descs, M_DEVBUF);
326 	free(chan->descs_phys, M_DEVBUF);
327 
328 	pmap_kremove_device(chan->mem_vaddr, chan->mem_size);
329 	kva_free(chan->mem_vaddr, chan->mem_size);
330 	vmem_free(xchan->vmem, chan->mem_paddr, chan->mem_size);
331 
332 	return (0);
333 }
334 
335 static int
336 axidma_desc_alloc(struct axidma_softc *sc, struct xdma_channel *xchan,
337     uint32_t desc_size)
338 {
339 	struct axidma_channel *chan;
340 	int nsegments;
341 	int i;
342 
343 	chan = (struct axidma_channel *)xchan->chan;
344 	nsegments = chan->descs_num;
345 
346 	chan->descs = malloc(nsegments * sizeof(struct axidma_desc *),
347 	    M_DEVBUF, M_NOWAIT | M_ZERO);
348 	if (chan->descs == NULL) {
349 		device_printf(sc->dev,
350 		    "%s: Can't allocate memory.\n", __func__);
351 		return (-1);
352 	}
353 
354 	chan->descs_phys = malloc(nsegments * sizeof(bus_dma_segment_t),
355 	    M_DEVBUF, M_NOWAIT | M_ZERO);
356 	chan->mem_size = desc_size * nsegments;
357 	if (vmem_alloc(xchan->vmem, chan->mem_size, M_FIRSTFIT | M_NOWAIT,
358 	    &chan->mem_paddr)) {
359 		device_printf(sc->dev, "Failed to allocate memory.\n");
360 		return (-1);
361 	}
362 	chan->mem_vaddr = kva_alloc(chan->mem_size);
363 	pmap_kenter(chan->mem_vaddr, chan->mem_size, chan->mem_paddr,
364 	    VM_MEMATTR_DEFAULT);
365 
366 	device_printf(sc->dev, "Allocated chunk %lx %lu\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->caps |= XCHAN_CAP_BOUNCE;
403 		xchan->chan = (void *)chan;
404 		chan->sc = sc;
405 		chan->used = true;
406 		chan->idx_head = 0;
407 		chan->idx_tail = 0;
408 		chan->descs_used_count = 0;
409 		chan->descs_num = AXIDMA_DESCS_NUM;
410 
411 		return (0);
412 	}
413 
414 	return (-1);
415 }
416 
417 static int
418 axidma_channel_free(device_t dev, struct xdma_channel *xchan)
419 {
420 	struct axidma_channel *chan;
421 	struct axidma_softc *sc;
422 
423 	sc = device_get_softc(dev);
424 
425 	chan = (struct axidma_channel *)xchan->chan;
426 
427 	axidma_desc_free(sc, chan);
428 
429 	chan->used = false;
430 
431 	return (0);
432 }
433 
434 static int
435 axidma_channel_capacity(device_t dev, xdma_channel_t *xchan,
436     uint32_t *capacity)
437 {
438 	struct axidma_channel *chan;
439 	uint32_t c;
440 
441 	chan = (struct axidma_channel *)xchan->chan;
442 
443 	/* At least one descriptor must be left empty. */
444 	c = (chan->descs_num - chan->descs_used_count - 1);
445 
446 	*capacity = c;
447 
448 	return (0);
449 }
450 
451 static int
452 axidma_channel_submit_sg(device_t dev, struct xdma_channel *xchan,
453     struct xdma_sglist *sg, uint32_t sg_n)
454 {
455 	xdma_controller_t *xdma;
456 	struct axidma_fdt_data *data;
457 	struct axidma_channel *chan;
458 	struct axidma_desc *desc;
459 	struct axidma_softc *sc;
460 	uint32_t src_addr;
461 	uint32_t dst_addr;
462 	uint32_t addr;
463 	uint32_t len;
464 	uint32_t tmp;
465 	int i;
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 	tmp = 0;
479 
480 	for (i = 0; i < sg_n; i++) {
481 		src_addr = (uint32_t)sg[i].src_addr;
482 		dst_addr = (uint32_t)sg[i].dst_addr;
483 		len = (uint32_t)sg[i].len;
484 
485 		dprintf("%s(%d): src %x dst %x len %d\n", __func__,
486 		    data->id, src_addr, dst_addr, len);
487 
488 		desc = chan->descs[chan->idx_head];
489 		if (sg[i].direction == XDMA_MEM_TO_DEV)
490 			desc->phys = src_addr;
491 		else
492 			desc->phys = dst_addr;
493 		desc->status = 0;
494 		desc->control = len;
495 		if (sg[i].first == 1)
496 			desc->control |= BD_CONTROL_TXSOF;
497 		if (sg[i].last == 1)
498 			desc->control |= BD_CONTROL_TXEOF;
499 
500 		cpu_dcache_wbinv_range((vm_offset_t)desc,
501 		    sizeof(struct axidma_desc));
502 
503 		tmp = chan->idx_head;
504 
505 		atomic_add_int(&chan->descs_used_count, 1);
506 		chan->idx_head = axidma_next_desc(chan, chan->idx_head);
507 	}
508 
509 	dprintf("%s(%d): _curdesc %x\n", __func__, data->id,
510 	    READ8(sc, AXI_CURDESC(data->id)));
511 	dprintf("%s(%d): _curdesc %x\n", __func__, data->id,
512 	    READ8(sc, AXI_CURDESC(data->id)));
513 	dprintf("%s(%d): status %x\n", __func__, data->id,
514 	    READ4(sc, AXI_DMASR(data->id)));
515 
516 	addr = chan->descs_phys[tmp];
517 	WRITE8(sc, AXI_TAILDESC(data->id), addr);
518 
519 	return (0);
520 }
521 
522 static int
523 axidma_channel_prep_sg(device_t dev, struct xdma_channel *xchan)
524 {
525 	xdma_controller_t *xdma;
526 	struct axidma_fdt_data *data;
527 	struct axidma_channel *chan;
528 	struct axidma_desc *desc;
529 	struct axidma_softc *sc;
530 	uint32_t addr;
531 	uint32_t reg;
532 	int ret;
533 	int i;
534 
535 	sc = device_get_softc(dev);
536 
537 	chan = (struct axidma_channel *)xchan->chan;
538 	xdma = xchan->xdma;
539 	data = xdma->data;
540 
541 	dprintf("%s(%d)\n", __func__, data->id);
542 
543 	ret = axidma_desc_alloc(sc, xchan, sizeof(struct axidma_desc));
544 	if (ret != 0) {
545 		device_printf(sc->dev,
546 		    "%s: Can't allocate descriptors.\n", __func__);
547 		return (-1);
548 	}
549 
550 	for (i = 0; i < chan->descs_num; i++) {
551 		desc = chan->descs[i];
552 		bzero(desc, sizeof(struct axidma_desc));
553 
554 		if (i == (chan->descs_num - 1))
555 			desc->next = chan->descs_phys[0];
556 		else
557 			desc->next = chan->descs_phys[i + 1];
558 		desc->status = 0;
559 		desc->control = 0;
560 
561 		dprintf("%s(%d): desc %d vaddr %lx next paddr %x\n", __func__,
562 		    data->id, i, (uint64_t)desc, le32toh(desc->next));
563 	}
564 
565 	addr = chan->descs_phys[0];
566 	WRITE8(sc, AXI_CURDESC(data->id), addr);
567 
568 	reg = READ4(sc, AXI_DMACR(data->id));
569 	reg |= DMACR_IOC_IRQEN | DMACR_DLY_IRQEN | DMACR_ERR_IRQEN;
570 	WRITE4(sc, AXI_DMACR(data->id), reg);
571 	reg |= DMACR_RS;
572 	WRITE4(sc, AXI_DMACR(data->id), reg);
573 
574 	return (0);
575 }
576 
577 static int
578 axidma_channel_control(device_t dev, xdma_channel_t *xchan, int cmd)
579 {
580 
581 	switch (cmd) {
582 	case XDMA_CMD_BEGIN:
583 	case XDMA_CMD_TERMINATE:
584 	case XDMA_CMD_PAUSE:
585 		/* TODO: implement me */
586 		return (-1);
587 	}
588 
589 	return (0);
590 }
591 
592 #ifdef FDT
593 static int
594 axidma_ofw_md_data(device_t dev, pcell_t *cells, int ncells, void **ptr)
595 {
596 	struct axidma_fdt_data *data;
597 
598 	if (ncells != 1)
599 		return (-1);
600 
601 	data = malloc(sizeof(struct axidma_fdt_data),
602 	    M_DEVBUF, (M_WAITOK | M_ZERO));
603 	data->id = cells[0];
604 
605 	*ptr = data;
606 
607 	return (0);
608 }
609 #endif
610 
611 static device_method_t axidma_methods[] = {
612 	/* Device interface */
613 	DEVMETHOD(device_probe,			axidma_probe),
614 	DEVMETHOD(device_attach,		axidma_attach),
615 	DEVMETHOD(device_detach,		axidma_detach),
616 
617 	/* xDMA Interface */
618 	DEVMETHOD(xdma_channel_alloc,		axidma_channel_alloc),
619 	DEVMETHOD(xdma_channel_free,		axidma_channel_free),
620 	DEVMETHOD(xdma_channel_control,		axidma_channel_control),
621 
622 	/* xDMA SG Interface */
623 	DEVMETHOD(xdma_channel_capacity,	axidma_channel_capacity),
624 	DEVMETHOD(xdma_channel_prep_sg,		axidma_channel_prep_sg),
625 	DEVMETHOD(xdma_channel_submit_sg,	axidma_channel_submit_sg),
626 
627 #ifdef FDT
628 	DEVMETHOD(xdma_ofw_md_data,		axidma_ofw_md_data),
629 #endif
630 
631 	DEVMETHOD_END
632 };
633 
634 static driver_t axidma_driver = {
635 	"axidma",
636 	axidma_methods,
637 	sizeof(struct axidma_softc),
638 };
639 
640 EARLY_DRIVER_MODULE(axidma, simplebus, axidma_driver, 0, 0,
641     BUS_PASS_INTERRUPT + BUS_PASS_ORDER_LATE);
642