1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2010-2016 Solarflare Communications Inc.
5 * All rights reserved.
6 *
7 * This software was developed in part by Philip Paeps under contract for
8 * Solarflare Communications, Inc.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions are met:
12 *
13 * 1. Redistributions of source code must retain the above copyright notice,
14 *    this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright notice,
16 *    this list of conditions and the following disclaimer in the documentation
17 *    and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
20 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
21 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
23 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
24 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
25 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
26 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
27 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
28 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
29 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30 *
31 * The views and conclusions contained in the software and documentation are
32 * those of the authors and should not be interpreted as representing official
33 * policies, either expressed or implied, of the FreeBSD Project.
34 */
35
36#include <sys/cdefs.h>
37__FBSDID("$FreeBSD$");
38
39#include <sys/param.h>
40#include <sys/bus.h>
41#include <sys/kernel.h>
42#include <sys/malloc.h>
43#include <sys/queue.h>
44#include <sys/taskqueue.h>
45
46#include <machine/bus.h>
47
48#include "common/efx.h"
49
50#include "sfxge.h"
51
52static void
53sfxge_dma_cb(void *arg, bus_dma_segment_t *segs, int nseg, int error)
54{
55	bus_addr_t *addr;
56
57	addr = arg;
58
59	if (error != 0) {
60		*addr = 0;
61		return;
62	}
63
64	*addr = segs[0].ds_addr;
65}
66
67int
68sfxge_dma_map_sg_collapse(bus_dma_tag_t tag, bus_dmamap_t map,
69			  struct mbuf **mp, bus_dma_segment_t *segs,
70			  int *nsegs, int maxsegs)
71{
72	bus_dma_segment_t *psegs;
73	struct mbuf *m;
74	int seg_count;
75	int defragged;
76	int err;
77
78	m = *mp;
79	defragged = err = seg_count = 0;
80
81	KASSERT(m->m_pkthdr.len, ("packet has zero header length"));
82
83retry:
84	psegs = segs;
85	seg_count = 0;
86	if (m->m_next == NULL) {
87		sfxge_map_mbuf_fast(tag, map, m, segs);
88		*nsegs = 1;
89		return (0);
90	}
91#if defined(__i386__) || defined(__amd64__)
92	while (m != NULL && seg_count < maxsegs) {
93		/*
94		 * firmware doesn't like empty segments
95		 */
96		if (m->m_len != 0) {
97			seg_count++;
98			sfxge_map_mbuf_fast(tag, map, m, psegs);
99			psegs++;
100		}
101		m = m->m_next;
102	}
103#else
104	err = bus_dmamap_load_mbuf_sg(tag, map, *mp, segs, &seg_count, 0);
105#endif
106	if (seg_count == 0) {
107		err = EFBIG;
108		goto err_out;
109	} else if (err == EFBIG || seg_count >= maxsegs) {
110		if (!defragged) {
111			m = m_defrag(*mp, M_NOWAIT);
112			if (m == NULL) {
113				err = ENOBUFS;
114				goto err_out;
115			}
116			*mp = m;
117			defragged = 1;
118			goto retry;
119		}
120		err = EFBIG;
121		goto err_out;
122	}
123	*nsegs = seg_count;
124
125err_out:
126	return (err);
127}
128
129void
130sfxge_dma_free(efsys_mem_t *esmp)
131{
132
133	bus_dmamap_unload(esmp->esm_tag, esmp->esm_map);
134	bus_dmamem_free(esmp->esm_tag, esmp->esm_base, esmp->esm_map);
135	bus_dma_tag_destroy(esmp->esm_tag);
136
137	esmp->esm_addr = 0;
138	esmp->esm_base = NULL;
139}
140
141int
142sfxge_dma_alloc(struct sfxge_softc *sc, bus_size_t len, efsys_mem_t *esmp)
143{
144	void *vaddr;
145
146	/* Create the child DMA tag. */
147	if (bus_dma_tag_create(sc->parent_dma_tag, PAGE_SIZE, 0,
148	    MIN(0x3FFFFFFFFFFFUL, BUS_SPACE_MAXADDR), BUS_SPACE_MAXADDR, NULL,
149	    NULL, len, 1, len, 0, NULL, NULL, &esmp->esm_tag) != 0) {
150		device_printf(sc->dev, "Couldn't allocate txq DMA tag\n");
151		goto fail_tag_create;
152	}
153
154	/* Allocate kernel memory. */
155	if (bus_dmamem_alloc(esmp->esm_tag, (void **)&vaddr,
156	    BUS_DMA_WAITOK | BUS_DMA_COHERENT | BUS_DMA_ZERO,
157	    &esmp->esm_map) != 0) {
158		device_printf(sc->dev, "Couldn't allocate DMA memory\n");
159		goto fail_alloc;
160	}
161
162	/* Load map into device memory. */
163	if (bus_dmamap_load(esmp->esm_tag, esmp->esm_map, vaddr, len,
164	    sfxge_dma_cb, &esmp->esm_addr, 0) != 0) {
165		device_printf(sc->dev, "Couldn't load DMA mapping\n");
166		goto fail_load;
167	}
168
169	/*
170	 * The callback gets error information about the mapping
171	 * and will have set esm_addr to 0 if something went
172	 * wrong.
173	 */
174	if (esmp->esm_addr == 0)
175		goto fail_load_check;
176
177	esmp->esm_base = vaddr;
178
179	return (0);
180
181fail_load_check:
182fail_load:
183	bus_dmamem_free(esmp->esm_tag, vaddr, esmp->esm_map);
184fail_alloc:
185	bus_dma_tag_destroy(esmp->esm_tag);
186fail_tag_create:
187	return (ENOMEM);
188}
189
190void
191sfxge_dma_fini(struct sfxge_softc *sc)
192{
193
194	bus_dma_tag_destroy(sc->parent_dma_tag);
195}
196
197int
198sfxge_dma_init(struct sfxge_softc *sc)
199{
200
201	/* Create the parent dma tag. */
202	if (bus_dma_tag_create(bus_get_dma_tag(sc->dev),	/* parent */
203	    1, 0,			/* algnmnt, boundary */
204	    BUS_SPACE_MAXADDR,		/* lowaddr */
205	    BUS_SPACE_MAXADDR,		/* highaddr */
206	    NULL, NULL,			/* filter, filterarg */
207	    BUS_SPACE_MAXSIZE_32BIT,	/* maxsize */
208	    BUS_SPACE_UNRESTRICTED,	/* nsegments */
209	    BUS_SPACE_MAXSIZE_32BIT,	/* maxsegsize */
210	    0,				/* flags */
211	    NULL, NULL,			/* lock, lockarg */
212	    &sc->parent_dma_tag) != 0) {
213		device_printf(sc->dev, "Cannot allocate parent DMA tag\n");
214		return (ENOMEM);
215	}
216
217	return (0);
218}
219