xref: /netbsd-src/sys/arch/riscv/fdt/fdt_dma_machdep.c (revision 75b842b84762e0251223b719bf77fbef2e651bf6)

/*	$NetBSD: fdt_dma_machdep.c,v 1.2 2023/05/07 12:41:48 skrll Exp $	*/

/*-
 * Copyright (c) 2022 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Nick Hudson
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: fdt_dma_machdep.c,v 1.2 2023/05/07 12:41:48 skrll Exp $");

#include <sys/param.h>
#include <sys/bus.h>
#include <sys/kmem.h>

#include <dev/fdt/fdtvar.h>

extern struct riscv_bus_dma_tag riscv_generic_dma_tag;

bus_dma_tag_t
fdtbus_dma_tag_create(int phandle, const struct fdt_dma_range *ranges,
    u_int nranges)
{
	struct riscv_bus_dma_tag *tagp;
	u_int n;

	// Check bindings.
	const int flags = of_hasprop(phandle, "dma-coherent") ?
	    _BUS_DMAMAP_COHERENT : 0;

	tagp = kmem_alloc(sizeof(*tagp), KM_SLEEP);
	*tagp = riscv_generic_dma_tag;
	if (nranges == 0) {
		tagp->_nranges = 1;
		tagp->_ranges = kmem_alloc(sizeof(*tagp->_ranges), KM_SLEEP);
		tagp->_ranges[0].dr_sysbase = 0;
		tagp->_ranges[0].dr_busbase = 0;
		tagp->_ranges[0].dr_len = UINTPTR_MAX;
		tagp->_ranges[0].dr_flags = flags;
	} else {
		tagp->_nranges = nranges;
		tagp->_ranges = kmem_alloc(sizeof(*tagp->_ranges) * nranges,
		    KM_SLEEP);
		for (n = 0; n < nranges; n++) {
			tagp->_ranges[n].dr_sysbase = ranges[n].dr_sysbase;
			tagp->_ranges[n].dr_busbase = ranges[n].dr_busbase;
			tagp->_ranges[n].dr_len = ranges[n].dr_len;
			tagp->_ranges[n].dr_flags = flags;
		}
	}

	return tagp;
}