1// SPDX-License-Identifier: GPL-1.0+
2/*
3 * OHCI HCD (Host Controller Driver) for USB.
4 *
5 * (C) Copyright 1999 Roman Weissgaerber <weissg@vienna.at>
6 * (C) Copyright 2000-2002 David Brownell <dbrownell@users.sourceforge.net>
7 *
8 * This file is licenced under the GPL.
9 */
10
11/*-------------------------------------------------------------------------*/
12
13/*
14 * OHCI deals with three types of memory:
15 * - data used only by the HCD ... kmalloc is fine
16 * - async and periodic schedules, shared by HC and HCD ... these
17 * need to use dma_pool or dma_alloc_coherent
18 * - driver buffers, read/written by HC ... the hcd glue or the
19 * device driver provides us with dma addresses
20 *
21 * There's also "register" data, which is memory mapped.
22 * No memory seen by this driver (or any HCD) may be paged out.
23 */
24
25/*-------------------------------------------------------------------------*/
26
27static void ohci_hcd_init (struct ohci_hcd *ohci)
28{
29 ohci->next_statechange = jiffies;
30 spin_lock_init (&ohci->lock);
31 INIT_LIST_HEAD (list: &ohci->pending);
32 INIT_LIST_HEAD(list: &ohci->eds_in_use);
33}
34
35/*-------------------------------------------------------------------------*/
36
37static int ohci_mem_init (struct ohci_hcd *ohci)
38{
39 /*
40 * HCs with local memory allocate from localmem_pool so there's
41 * no need to create the below dma pools.
42 */
43 if (ohci_to_hcd(ohci)->localmem_pool)
44 return 0;
45
46 ohci->td_cache = dma_pool_create (name: "ohci_td",
47 dev: ohci_to_hcd(ohci)->self.controller,
48 size: sizeof (struct td),
49 align: 32 /* byte alignment */,
50 allocation: 0 /* no page-crossing issues */);
51 if (!ohci->td_cache)
52 return -ENOMEM;
53 ohci->ed_cache = dma_pool_create (name: "ohci_ed",
54 dev: ohci_to_hcd(ohci)->self.controller,
55 size: sizeof (struct ed),
56 align: 16 /* byte alignment */,
57 allocation: 0 /* no page-crossing issues */);
58 if (!ohci->ed_cache) {
59 dma_pool_destroy (pool: ohci->td_cache);
60 return -ENOMEM;
61 }
62 return 0;
63}
64
65static void ohci_mem_cleanup (struct ohci_hcd *ohci)
66{
67 dma_pool_destroy(pool: ohci->td_cache);
68 ohci->td_cache = NULL;
69 dma_pool_destroy(pool: ohci->ed_cache);
70 ohci->ed_cache = NULL;
71}
72
73/*-------------------------------------------------------------------------*/
74
75/* ohci "done list" processing needs this mapping */
76static inline struct td *
77dma_to_td (struct ohci_hcd *hc, dma_addr_t td_dma)
78{
79 struct td *td;
80
81 td_dma &= TD_MASK;
82 td = hc->td_hash [TD_HASH_FUNC(td_dma)];
83 while (td && td->td_dma != td_dma)
84 td = td->td_hash;
85 return td;
86}
87
88/* TDs ... */
89static struct td *
90td_alloc (struct ohci_hcd *hc, gfp_t mem_flags)
91{
92 dma_addr_t dma;
93 struct td *td;
94 struct usb_hcd *hcd = ohci_to_hcd(ohci: hc);
95
96 if (hcd->localmem_pool)
97 td = gen_pool_dma_zalloc_align(pool: hcd->localmem_pool,
98 size: sizeof(*td), dma: &dma, align: 32);
99 else
100 td = dma_pool_zalloc(pool: hc->td_cache, mem_flags, handle: &dma);
101 if (td) {
102 /* in case hc fetches it, make it look dead */
103 td->hwNextTD = cpu_to_hc32 (ohci: hc, x: dma);
104 td->td_dma = dma;
105 /* hashed in td_fill */
106 }
107 return td;
108}
109
110static void
111td_free (struct ohci_hcd *hc, struct td *td)
112{
113 struct td **prev = &hc->td_hash [TD_HASH_FUNC (td->td_dma)];
114 struct usb_hcd *hcd = ohci_to_hcd(ohci: hc);
115
116 while (*prev && *prev != td)
117 prev = &(*prev)->td_hash;
118 if (*prev)
119 *prev = td->td_hash;
120 else if ((td->hwINFO & cpu_to_hc32(ohci: hc, TD_DONE)) != 0)
121 ohci_dbg (hc, "no hash for td %p\n", td);
122
123 if (hcd->localmem_pool)
124 gen_pool_free(pool: hcd->localmem_pool, addr: (unsigned long)td,
125 size: sizeof(*td));
126 else
127 dma_pool_free(pool: hc->td_cache, vaddr: td, addr: td->td_dma);
128}
129
130/*-------------------------------------------------------------------------*/
131
132/* EDs ... */
133static struct ed *
134ed_alloc (struct ohci_hcd *hc, gfp_t mem_flags)
135{
136 dma_addr_t dma;
137 struct ed *ed;
138 struct usb_hcd *hcd = ohci_to_hcd(ohci: hc);
139
140 if (hcd->localmem_pool)
141 ed = gen_pool_dma_zalloc_align(pool: hcd->localmem_pool,
142 size: sizeof(*ed), dma: &dma, align: 16);
143 else
144 ed = dma_pool_zalloc(pool: hc->ed_cache, mem_flags, handle: &dma);
145 if (ed) {
146 INIT_LIST_HEAD (list: &ed->td_list);
147 ed->dma = dma;
148 }
149 return ed;
150}
151
152static void
153ed_free (struct ohci_hcd *hc, struct ed *ed)
154{
155 struct usb_hcd *hcd = ohci_to_hcd(ohci: hc);
156
157 if (hcd->localmem_pool)
158 gen_pool_free(pool: hcd->localmem_pool, addr: (unsigned long)ed,
159 size: sizeof(*ed));
160 else
161 dma_pool_free(pool: hc->ed_cache, vaddr: ed, addr: ed->dma);
162}
163
164

source code of linux/drivers/usb/host/ohci-mem.c