aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/usb/host/ohci-mem.c
blob: 2f20d3dc895b8b4a959459573f4089e2014f27f8 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
/*
 * OHCI HCD (Host Controller Driver) for USB.
 *
 * (C) Copyright 1999 Roman Weissgaerber <weissg@vienna.at>
 * (C) Copyright 2000-2002 David Brownell <dbrownell@users.sourceforge.net>
 *
 * This file is licenced under the GPL.
 */

/*-------------------------------------------------------------------------*/

/*
 * OHCI deals with three types of memory:
 *	- data used only by the HCD ... kmalloc is fine
 *	- async and periodic schedules, shared by HC and HCD ... these
 *	  need to use dma_pool or dma_alloc_coherent
 *	- driver buffers, read/written by HC ... the hcd glue or the
 *	  device driver provides us with dma addresses
 *
 * There's also "register" data, which is memory mapped.
 * No memory seen by this driver (or any HCD) may be paged out.
 */

/*-------------------------------------------------------------------------*/

static void ohci_hcd_init (struct ohci_hcd *ohci)
{
	ohci->next_statechange = jiffies;
	spin_lock_init (&ohci->lock);
	INIT_LIST_HEAD (&ohci->pending);
}

/*-------------------------------------------------------------------------*/

static int ohci_mem_init (struct ohci_hcd *ohci)
{
	ohci->td_cache = dma_pool_create ("ohci_td",
		ohci_to_hcd(ohci)->self.controller,
		sizeof (struct td),
		32 /* byte alignment */,
		0 /* no page-crossing issues */);
	if (!ohci->td_cache)
		return -ENOMEM;
	ohci->ed_cache = dma_pool_create ("ohci_ed",
		ohci_to_hcd(ohci)->self.controller,
		sizeof (struct ed),
		16 /* byte alignment */,
		0 /* no page-crossing issues */);
	if (!ohci->ed_cache) {
		dma_pool_destroy (ohci->td_cache);
		return -ENOMEM;
	}
	return 0;
}

static void ohci_mem_cleanup (struct ohci_hcd *ohci)
{
	if (ohci->td_cache) {
		dma_pool_destroy (ohci->td_cache);
		ohci->td_cache = NULL;
	}
	if (ohci->ed_cache) {
		dma_pool_destroy (ohci->ed_cache);
		ohci->ed_cache = NULL;
	}
}

/*-------------------------------------------------------------------------*/

/* ohci "done list" processing needs this mapping */
static inline struct td *
dma_to_td (struct ohci_hcd *hc, dma_addr_t td_dma)
{
	struct td *td;

	td_dma &= TD_MASK;
	td = hc->td_hash [TD_HASH_FUNC(td_dma)];
	while (td && td->td_dma != td_dma)
		td = td->td_hash;
	return td;
}

/* TDs ... */
static struct td *
td_alloc (struct ohci_hcd *hc, gfp_t mem_flags)
{
	dma_addr_t	dma;
	struct td	*td;

	td = dma_pool_alloc (hc->td_cache, mem_flags, &dma);
	if (td) {
		/* in case hc fetches it, make it look dead */
		memset (td, 0, sizeof *td);
		td->hwNextTD = cpu_to_hc32 (hc, dma);
		td->td_dma = dma;
		/* hashed in td_fill */
	}
	return td;
}

static void
td_free (struct ohci_hcd *hc, struct td *td)
{
	struct td	**prev = &hc->td_hash [TD_HASH_FUNC (td->td_dma)];

	while (*prev && *prev != td)
		prev = &(*prev)->td_hash;
	if (*prev)
		*prev = td->td_hash;
	else if ((td->hwINFO & cpu_to_hc32(hc, TD_DONE)) != 0)
		ohci_dbg (hc, "no hash for td %p\n", td);
	dma_pool_free (hc->td_cache, td, td->td_dma);
}

/*-------------------------------------------------------------------------*/

/* EDs ... */
static struct ed *
ed_alloc (struct ohci_hcd *hc, gfp_t mem_flags)
{
	dma_addr_t	dma;
	struct ed	*ed;

	ed = dma_pool_alloc (hc->ed_cache, mem_flags, &dma);
	if (ed) {
		memset (ed, 0, sizeof (*ed));
		INIT_LIST_HEAD (&ed->td_list);
		ed->dma = dma;
	}
	return ed;
}

static void
ed_free (struct ohci_hcd *hc, struct ed *ed)
{
	dma_pool_free (hc->ed_cache, ed, ed->dma);
}