xref: /freebsd/sys/dev/xdma/xdma_sglist.c (revision 5ca8e32633c4ffbbcd6762e5888b6a4ba0708c6c)
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 #include "opt_platform.h"
33 #include <sys/param.h>
34 #include <sys/conf.h>
35 #include <sys/bus.h>
36 #include <sys/kernel.h>
37 #include <sys/malloc.h>
38 
39 #include <machine/bus.h>
40 
41 #include <dev/xdma/xdma.h>
42 
43 int
44 xchan_sglist_alloc(xdma_channel_t *xchan)
45 {
46 	uint32_t sz;
47 
48 	if (xchan->flags & XCHAN_SGLIST_ALLOCATED)
49 		return (-1);
50 
51 	sz = (sizeof(struct xdma_sglist) * XDMA_SGLIST_MAXLEN);
52 	xchan->sg = malloc(sz, M_XDMA, M_WAITOK | M_ZERO);
53 	xchan->flags |= XCHAN_SGLIST_ALLOCATED;
54 
55 	return (0);
56 }
57 
58 void
59 xchan_sglist_free(xdma_channel_t *xchan)
60 {
61 
62 	if (xchan->flags & XCHAN_SGLIST_ALLOCATED)
63 		free(xchan->sg, M_XDMA);
64 
65 	xchan->flags &= ~XCHAN_SGLIST_ALLOCATED;
66 }
67 
68 int
69 xdma_sglist_add(struct xdma_sglist *sg, struct bus_dma_segment *seg,
70     uint32_t nsegs, struct xdma_request *xr)
71 {
72 	int i;
73 
74 	if (nsegs == 0)
75 		return (-1);
76 
77 	for (i = 0; i < nsegs; i++) {
78 		sg[i].src_width = xr->src_width;
79 		sg[i].dst_width = xr->dst_width;
80 
81 		if (xr->direction == XDMA_MEM_TO_DEV) {
82 			sg[i].src_addr = seg[i].ds_addr;
83 			sg[i].dst_addr = xr->dst_addr;
84 		} else {
85 			sg[i].src_addr = xr->src_addr;
86 			sg[i].dst_addr = seg[i].ds_addr;
87 		}
88 		sg[i].len = seg[i].ds_len;
89 		sg[i].direction = xr->direction;
90 
91 		sg[i].first = 0;
92 		sg[i].last = 0;
93 	}
94 
95 	sg[0].first = 1;
96 	sg[nsegs - 1].last = 1;
97 
98 	return (0);
99 }
100