xref: /freebsd/sys/dev/xdma/xdma_sglist.c (revision cc68614da8232d8baaca0ae0d0dd8f890f06623e)
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/malloc.h>
40 
41 #include <machine/bus.h>
42 
43 #include <dev/xdma/xdma.h>
44 
45 int
46 xchan_sglist_alloc(xdma_channel_t *xchan)
47 {
48 	uint32_t sz;
49 
50 	if (xchan->flags & XCHAN_SGLIST_ALLOCATED)
51 		return (-1);
52 
53 	sz = (sizeof(struct xdma_sglist) * XDMA_SGLIST_MAXLEN);
54 	xchan->sg = malloc(sz, M_XDMA, M_WAITOK | M_ZERO);
55 	xchan->flags |= XCHAN_SGLIST_ALLOCATED;
56 
57 	return (0);
58 }
59 
60 void
61 xchan_sglist_free(xdma_channel_t *xchan)
62 {
63 
64 	if (xchan->flags & XCHAN_SGLIST_ALLOCATED)
65 		free(xchan->sg, M_XDMA);
66 
67 	xchan->flags &= ~XCHAN_SGLIST_ALLOCATED;
68 }
69 
70 int
71 xdma_sglist_add(struct xdma_sglist *sg, struct bus_dma_segment *seg,
72     uint32_t nsegs, struct xdma_request *xr)
73 {
74 	int i;
75 
76 	if (nsegs == 0)
77 		return (-1);
78 
79 	for (i = 0; i < nsegs; i++) {
80 		sg[i].src_width = xr->src_width;
81 		sg[i].dst_width = xr->dst_width;
82 
83 		if (xr->direction == XDMA_MEM_TO_DEV) {
84 			sg[i].src_addr = seg[i].ds_addr;
85 			sg[i].dst_addr = xr->dst_addr;
86 		} else {
87 			sg[i].src_addr = xr->src_addr;
88 			sg[i].dst_addr = seg[i].ds_addr;
89 		}
90 		sg[i].len = seg[i].ds_len;
91 		sg[i].direction = xr->direction;
92 
93 		sg[i].first = 0;
94 		sg[i].last = 0;
95 	}
96 
97 	sg[0].first = 1;
98 	sg[nsegs - 1].last = 1;
99 
100 	return (0);
101 }
102