1/*
2 * arch/sh/drivers/pci/dma-dreamcast.c
3 *
4 * PCI DMA support for the Sega Dreamcast
5 *
6 * Copyright (C) 2001, 2002  M. R. Brown
7 * Copyright (C) 2002, 2003  Paul Mundt
8 *
9 * This file originally bore the message (with enclosed-$):
10 *	Id: pci.c,v 1.3 2003/05/04 19:29:46 lethal Exp
11 *	Dreamcast PCI: Supports SEGA Broadband Adaptor only.
12 *
13 * This file is subject to the terms and conditions of the GNU General Public
14 * License.  See the file "COPYING" in the main directory of this archive
15 * for more details.
16 */
17
18#include <linux/sched.h>
19#include <linux/kernel.h>
20#include <linux/param.h>
21#include <linux/interrupt.h>
22#include <linux/init.h>
23#include <linux/irq.h>
24#include <linux/pci.h>
25#include <linux/dma-mapping.h>
26#include <linux/device.h>
27
28#include <asm/io.h>
29#include <asm/irq.h>
30#include <asm/mach/pci.h>
31
32static int gapspci_dma_used = 0;
33
34void *dreamcast_consistent_alloc(struct device *dev, size_t size,
35				 dma_addr_t *dma_handle, gfp_t flag)
36{
37	unsigned long buf;
38
39	if (dev && dev->bus != &pci_bus_type)
40		return NULL;
41
42	if (gapspci_dma_used + size > GAPSPCI_DMA_SIZE)
43		return ERR_PTR(-EINVAL);
44
45	buf = GAPSPCI_DMA_BASE + gapspci_dma_used;
46
47	gapspci_dma_used = PAGE_ALIGN(gapspci_dma_used+size);
48
49	*dma_handle = (dma_addr_t)buf;
50
51	buf = P2SEGADDR(buf);
52
53	/* Flush the dcache before we hand off the buffer */
54	dma_cache_wback_inv((void *)buf, size);
55
56	return (void *)buf;
57}
58
59int dreamcast_consistent_free(struct device *dev, size_t size,
60			 void *vaddr, dma_addr_t dma_handle)
61{
62	if (dev && dev->bus != &pci_bus_type)
63		return -EINVAL;
64
65	gapspci_dma_used = 0;
66
67	return 0;
68}
69