xref: /freebsd/sys/dev/xdma/xdma_mbuf.c (revision f3c5273d315a64826d2149ac453ff8c4583ddbe8)
1 /*-
2  * Copyright (c) 2017-2018 Ruslan Bukin <br@bsdpad.com>
3  * All rights reserved.
4  *
5  * This software was developed by SRI International and the University of
6  * Cambridge Computer Laboratory under DARPA/AFRL contract FA8750-10-C-0237
7  * ("CTSRD"), as part of the DARPA CRASH research programme.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 
31 #include <sys/cdefs.h>
32 __FBSDID("$FreeBSD$");
33 
34 #include "opt_platform.h"
35 #include <sys/param.h>
36 #include <sys/conf.h>
37 #include <sys/bus.h>
38 #include <sys/kernel.h>
39 #include <sys/sx.h>
40 #include <sys/mbuf.h>
41 
42 #include <machine/bus.h>
43 
44 #ifdef FDT
45 #include <dev/fdt/fdt_common.h>
46 #include <dev/ofw/ofw_bus.h>
47 #include <dev/ofw/ofw_bus_subr.h>
48 #endif
49 
50 #include <dev/xdma/xdma.h>
51 
52 int
53 xdma_dequeue_mbuf(xdma_channel_t *xchan, struct mbuf **mp,
54     xdma_transfer_status_t *status)
55 {
56 	struct xdma_request *xr;
57 	struct xdma_request *xr_tmp;
58 
59 	QUEUE_OUT_LOCK(xchan);
60 	TAILQ_FOREACH_SAFE(xr, &xchan->queue_out, xr_next, xr_tmp) {
61 		TAILQ_REMOVE(&xchan->queue_out, xr, xr_next);
62 		break;
63 	}
64 	QUEUE_OUT_UNLOCK(xchan);
65 
66 	if (xr == NULL)
67 		return (-1);
68 
69 	*mp = xr->m;
70 	status->error = xr->status.error;
71 	status->transferred = xr->status.transferred;
72 
73 	xchan_bank_put(xchan, xr);
74 
75 	return (0);
76 }
77 
78 int
79 xdma_enqueue_mbuf(xdma_channel_t *xchan, struct mbuf **mp,
80     uintptr_t addr, uint8_t src_width, uint8_t dst_width,
81     enum xdma_direction dir)
82 {
83 	struct xdma_request *xr;
84 	xdma_controller_t *xdma;
85 
86 	xdma = xchan->xdma;
87 
88 	xr = xchan_bank_get(xchan);
89 	if (xr == NULL)
90 		return (-1); /* No space is available yet. */
91 
92 	xr->direction = dir;
93 	xr->m = *mp;
94 	xr->req_type = XR_TYPE_MBUF;
95 	if (dir == XDMA_MEM_TO_DEV) {
96 		xr->dst_addr = addr;
97 		xr->src_addr = 0;
98 	} else {
99 		xr->src_addr = addr;
100 		xr->dst_addr = 0;
101 	}
102 	xr->src_width = src_width;
103 	xr->dst_width = dst_width;
104 
105 	QUEUE_IN_LOCK(xchan);
106 	TAILQ_INSERT_TAIL(&xchan->queue_in, xr, xr_next);
107 	QUEUE_IN_UNLOCK(xchan);
108 
109 	return (0);
110 }
111 
112 uint32_t
113 xdma_mbuf_chain_count(struct mbuf *m0)
114 {
115 	struct mbuf *m;
116 	uint32_t c;
117 
118 	c = 0;
119 
120 	for (m = m0; m != NULL; m = m->m_next)
121 		c++;
122 
123 	return (c);
124 }
125 
126 uint32_t
127 xdma_mbuf_defrag(xdma_channel_t *xchan, struct xdma_request *xr)
128 {
129 	xdma_controller_t *xdma;
130 	struct mbuf *m;
131 	uint32_t c;
132 
133 	xdma = xchan->xdma;
134 
135 	c = xdma_mbuf_chain_count(xr->m);
136 	if (c == 1)
137 		return (c); /* Nothing to do. */
138 
139 	if (xchan->caps & XCHAN_CAP_BUSDMA) {
140 		if ((xchan->caps & XCHAN_CAP_BUSDMA_NOSEG) || \
141 		    (c > xchan->maxnsegs)) {
142 			if ((m = m_defrag(xr->m, M_NOWAIT)) == NULL) {
143 				device_printf(xdma->dma_dev,
144 				    "%s: Can't defrag mbuf\n",
145 				    __func__);
146 				return (c);
147 			}
148 			xr->m = m;
149 			c = 1;
150 		}
151 	}
152 
153 	return (c);
154 }
155