1/*
2 * arch/sh/cchips/voyagergx/consistent.c
3 *
4 * Copyright (C) 2004  Paul Mundt
5 *
6 * This file is subject to the terms and conditions of the GNU General Public
7 * License.  See the file "COPYING" in the main directory of this archive
8 * for more details.
9 */
10#include <linux/mm.h>
11#include <linux/dma-mapping.h>
12#include <linux/slab.h>
13#include <linux/list.h>
14#include <linux/types.h>
15#include <linux/module.h>
16#include <linux/device.h>
17#include <asm/io.h>
18
19
20struct voya_alloc_entry {
21	struct list_head list;
22	unsigned long ofs;
23	unsigned long len;
24};
25
26static DEFINE_SPINLOCK(voya_list_lock);
27static LIST_HEAD(voya_alloc_list);
28
29#define OHCI_SRAM_START	0xb0000000
30#define OHCI_HCCA_SIZE	0x100
31#define OHCI_SRAM_SIZE	0x10000
32
33#define VOYAGER_OHCI_NAME	"voyager-ohci"
34
35void *voyagergx_consistent_alloc(struct device *dev, size_t size,
36				 dma_addr_t *handle, gfp_t flag)
37{
38	struct list_head *list = &voya_alloc_list;
39	struct voya_alloc_entry *entry;
40	unsigned long start, end;
41	unsigned long flags;
42
43	/*
44	 * The SM501 contains an integrated 8051 with its own SRAM.
45	 * Devices within the cchip can all hook into the 8051 SRAM.
46	 * We presently use this for the OHCI.
47	 *
48	 * Everything else goes through consistent_alloc().
49	 */
50	if (!dev || strcmp(dev->driver->name, VOYAGER_OHCI_NAME))
51		return NULL;
52
53	start = OHCI_SRAM_START + OHCI_HCCA_SIZE;
54
55	entry = kmalloc(sizeof(struct voya_alloc_entry), GFP_ATOMIC);
56	if (!entry)
57		return ERR_PTR(-ENOMEM);
58
59	entry->len = (size + 15) & ~15;
60
61	/*
62	 * The basis for this allocator is dwmw2's malloc.. the
63	 * Matrox allocator :-)
64	 */
65	spin_lock_irqsave(&voya_list_lock, flags);
66	list_for_each(list, &voya_alloc_list) {
67		struct voya_alloc_entry *p;
68
69		p = list_entry(list, struct voya_alloc_entry, list);
70
71		if (p->ofs - start >= size)
72			goto out;
73
74		start = p->ofs + p->len;
75	}
76
77	end  = start + (OHCI_SRAM_SIZE  - OHCI_HCCA_SIZE);
78	list = &voya_alloc_list;
79
80	if (end - start >= size) {
81out:
82		entry->ofs = start;
83		list_add_tail(&entry->list, list);
84		spin_unlock_irqrestore(&voya_list_lock, flags);
85
86		*handle = start;
87		return (void *)start;
88	}
89
90	kfree(entry);
91	spin_unlock_irqrestore(&voya_list_lock, flags);
92
93	return ERR_PTR(-EINVAL);
94}
95
96int voyagergx_consistent_free(struct device *dev, size_t size,
97			      void *vaddr, dma_addr_t handle)
98{
99	struct voya_alloc_entry *entry;
100	unsigned long flags;
101
102	if (!dev || strcmp(dev->driver->name, VOYAGER_OHCI_NAME))
103		return -EINVAL;
104
105	spin_lock_irqsave(&voya_list_lock, flags);
106	list_for_each_entry(entry, &voya_alloc_list, list) {
107		if (entry->ofs != handle)
108			continue;
109
110		list_del(&entry->list);
111		kfree(entry);
112
113		break;
114	}
115	spin_unlock_irqrestore(&voya_list_lock, flags);
116
117	return 0;
118}
119
120EXPORT_SYMBOL(voyagergx_consistent_alloc);
121EXPORT_SYMBOL(voyagergx_consistent_free);
122