xref: /openbmc/linux/drivers/usb/host/ohci-mem.c (revision ff2437be)
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 
ohci_hcd_init(struct ohci_hcd * ohci)27 static void ohci_hcd_init (struct ohci_hcd *ohci)
28 {
29 	ohci->next_statechange = jiffies;
30 	spin_lock_init (&ohci->lock);
31 	INIT_LIST_HEAD (&ohci->pending);
32 	INIT_LIST_HEAD(&ohci->eds_in_use);
33 }
34 
35 /*-------------------------------------------------------------------------*/
36 
ohci_mem_init(struct ohci_hcd * ohci)37 static 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 ("ohci_td",
47 		ohci_to_hcd(ohci)->self.controller,
48 		sizeof (struct td),
49 		32 /* byte alignment */,
50 		0 /* no page-crossing issues */);
51 	if (!ohci->td_cache)
52 		return -ENOMEM;
53 	ohci->ed_cache = dma_pool_create ("ohci_ed",
54 		ohci_to_hcd(ohci)->self.controller,
55 		sizeof (struct ed),
56 		16 /* byte alignment */,
57 		0 /* no page-crossing issues */);
58 	if (!ohci->ed_cache) {
59 		dma_pool_destroy (ohci->td_cache);
60 		return -ENOMEM;
61 	}
62 	return 0;
63 }
64 
ohci_mem_cleanup(struct ohci_hcd * ohci)65 static void ohci_mem_cleanup (struct ohci_hcd *ohci)
66 {
67 	dma_pool_destroy(ohci->td_cache);
68 	ohci->td_cache = NULL;
69 	dma_pool_destroy(ohci->ed_cache);
70 	ohci->ed_cache = NULL;
71 }
72 
73 /*-------------------------------------------------------------------------*/
74 
75 /* ohci "done list" processing needs this mapping */
76 static inline struct td *
dma_to_td(struct ohci_hcd * hc,dma_addr_t td_dma)77 dma_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 ... */
89 static struct td *
td_alloc(struct ohci_hcd * hc,gfp_t mem_flags)90 td_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(hc);
95 
96 	if (hcd->localmem_pool)
97 		td = gen_pool_dma_zalloc_align(hcd->localmem_pool,
98 				sizeof(*td), &dma, 32);
99 	else
100 		td = dma_pool_zalloc(hc->td_cache, mem_flags, &dma);
101 	if (td) {
102 		/* in case hc fetches it, make it look dead */
103 		td->hwNextTD = cpu_to_hc32 (hc, dma);
104 		td->td_dma = dma;
105 		/* hashed in td_fill */
106 	}
107 	return td;
108 }
109 
110 static void
td_free(struct ohci_hcd * hc,struct td * td)111 td_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(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(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(hcd->localmem_pool, (unsigned long)td,
125 			      sizeof(*td));
126 	else
127 		dma_pool_free(hc->td_cache, td, td->td_dma);
128 }
129 
130 /*-------------------------------------------------------------------------*/
131 
132 /* EDs ... */
133 static struct ed *
ed_alloc(struct ohci_hcd * hc,gfp_t mem_flags)134 ed_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(hc);
139 
140 	if (hcd->localmem_pool)
141 		ed = gen_pool_dma_zalloc_align(hcd->localmem_pool,
142 				sizeof(*ed), &dma, 16);
143 	else
144 		ed = dma_pool_zalloc(hc->ed_cache, mem_flags, &dma);
145 	if (ed) {
146 		INIT_LIST_HEAD (&ed->td_list);
147 		ed->dma = dma;
148 	}
149 	return ed;
150 }
151 
152 static void
ed_free(struct ohci_hcd * hc,struct ed * ed)153 ed_free (struct ohci_hcd *hc, struct ed *ed)
154 {
155 	struct usb_hcd	*hcd = ohci_to_hcd(hc);
156 
157 	if (hcd->localmem_pool)
158 		gen_pool_free(hcd->localmem_pool, (unsigned long)ed,
159 			      sizeof(*ed));
160 	else
161 		dma_pool_free(hc->ed_cache, ed, ed->dma);
162 }
163 
164