xref: /netbsd-src/sys/arch/riscv/fdt/fdt_dma_machdep.c (revision 75b842b84762e0251223b719bf77fbef2e651bf6)
1 /*	$NetBSD: fdt_dma_machdep.c,v 1.2 2023/05/07 12:41:48 skrll Exp $	*/
2 
3 /*-
4  * Copyright (c) 2022 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Nick Hudson
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 __KERNEL_RCSID(0, "$NetBSD: fdt_dma_machdep.c,v 1.2 2023/05/07 12:41:48 skrll Exp $");
34 
35 #include <sys/param.h>
36 #include <sys/bus.h>
37 #include <sys/kmem.h>
38 
39 #include <dev/fdt/fdtvar.h>
40 
41 extern struct riscv_bus_dma_tag riscv_generic_dma_tag;
42 
43 bus_dma_tag_t
fdtbus_dma_tag_create(int phandle,const struct fdt_dma_range * ranges,u_int nranges)44 fdtbus_dma_tag_create(int phandle, const struct fdt_dma_range *ranges,
45     u_int nranges)
46 {
47 	struct riscv_bus_dma_tag *tagp;
48 	u_int n;
49 
50 	// Check bindings.
51 	const int flags = of_hasprop(phandle, "dma-coherent") ?
52 	    _BUS_DMAMAP_COHERENT : 0;
53 
54 	tagp = kmem_alloc(sizeof(*tagp), KM_SLEEP);
55 	*tagp = riscv_generic_dma_tag;
56 	if (nranges == 0) {
57 		tagp->_nranges = 1;
58 		tagp->_ranges = kmem_alloc(sizeof(*tagp->_ranges), KM_SLEEP);
59 		tagp->_ranges[0].dr_sysbase = 0;
60 		tagp->_ranges[0].dr_busbase = 0;
61 		tagp->_ranges[0].dr_len = UINTPTR_MAX;
62 		tagp->_ranges[0].dr_flags = flags;
63 	} else {
64 		tagp->_nranges = nranges;
65 		tagp->_ranges = kmem_alloc(sizeof(*tagp->_ranges) * nranges,
66 		    KM_SLEEP);
67 		for (n = 0; n < nranges; n++) {
68 			tagp->_ranges[n].dr_sysbase = ranges[n].dr_sysbase;
69 			tagp->_ranges[n].dr_busbase = ranges[n].dr_busbase;
70 			tagp->_ranges[n].dr_len = ranges[n].dr_len;
71 			tagp->_ranges[n].dr_flags = flags;
72 		}
73 	}
74 
75 	return tagp;
76 }
77