xref: /openbmc/linux/drivers/usb/host/ehci-mem.c (revision 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2)
1 /*
2  * Copyright (c) 2001 by David Brownell
3  *
4  * This program is free software; you can redistribute it and/or modify it
5  * under the terms of the GNU General Public License as published by the
6  * Free Software Foundation; either version 2 of the License, or (at your
7  * option) any later version.
8  *
9  * This program is distributed in the hope that it will be useful, but
10  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
11  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12  * for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write to the Free Software Foundation,
16  * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
17  */
18 
19 /* this file is part of ehci-hcd.c */
20 
21 /*-------------------------------------------------------------------------*/
22 
23 /*
24  * There's basically three types of memory:
25  *	- data used only by the HCD ... kmalloc is fine
26  *	- async and periodic schedules, shared by HC and HCD ... these
27  *	  need to use dma_pool or dma_alloc_coherent
28  *	- driver buffers, read/written by HC ... single shot DMA mapped
29  *
30  * There's also PCI "register" data, which is memory mapped.
31  * No memory seen by this driver is pageable.
32  */
33 
34 /*-------------------------------------------------------------------------*/
35 
36 /* Allocate the key transfer structures from the previously allocated pool */
37 
38 static inline void ehci_qtd_init (struct ehci_qtd *qtd, dma_addr_t dma)
39 {
40 	memset (qtd, 0, sizeof *qtd);
41 	qtd->qtd_dma = dma;
42 	qtd->hw_token = cpu_to_le32 (QTD_STS_HALT);
43 	qtd->hw_next = EHCI_LIST_END;
44 	qtd->hw_alt_next = EHCI_LIST_END;
45 	INIT_LIST_HEAD (&qtd->qtd_list);
46 }
47 
48 static struct ehci_qtd *ehci_qtd_alloc (struct ehci_hcd *ehci, int flags)
49 {
50 	struct ehci_qtd		*qtd;
51 	dma_addr_t		dma;
52 
53 	qtd = dma_pool_alloc (ehci->qtd_pool, flags, &dma);
54 	if (qtd != NULL) {
55 		ehci_qtd_init (qtd, dma);
56 	}
57 	return qtd;
58 }
59 
60 static inline void ehci_qtd_free (struct ehci_hcd *ehci, struct ehci_qtd *qtd)
61 {
62 	dma_pool_free (ehci->qtd_pool, qtd, qtd->qtd_dma);
63 }
64 
65 
66 static void qh_destroy (struct kref *kref)
67 {
68 	struct ehci_qh *qh = container_of(kref, struct ehci_qh, kref);
69 	struct ehci_hcd *ehci = qh->ehci;
70 
71 	/* clean qtds first, and know this is not linked */
72 	if (!list_empty (&qh->qtd_list) || qh->qh_next.ptr) {
73 		ehci_dbg (ehci, "unused qh not empty!\n");
74 		BUG ();
75 	}
76 	if (qh->dummy)
77 		ehci_qtd_free (ehci, qh->dummy);
78 	usb_put_dev (qh->dev);
79 	dma_pool_free (ehci->qh_pool, qh, qh->qh_dma);
80 }
81 
82 static struct ehci_qh *ehci_qh_alloc (struct ehci_hcd *ehci, int flags)
83 {
84 	struct ehci_qh		*qh;
85 	dma_addr_t		dma;
86 
87 	qh = (struct ehci_qh *)
88 		dma_pool_alloc (ehci->qh_pool, flags, &dma);
89 	if (!qh)
90 		return qh;
91 
92 	memset (qh, 0, sizeof *qh);
93 	kref_init(&qh->kref);
94 	qh->ehci = ehci;
95 	qh->qh_dma = dma;
96 	// INIT_LIST_HEAD (&qh->qh_list);
97 	INIT_LIST_HEAD (&qh->qtd_list);
98 
99 	/* dummy td enables safe urb queuing */
100 	qh->dummy = ehci_qtd_alloc (ehci, flags);
101 	if (qh->dummy == NULL) {
102 		ehci_dbg (ehci, "no dummy td\n");
103 		dma_pool_free (ehci->qh_pool, qh, qh->qh_dma);
104 		qh = NULL;
105 	}
106 	return qh;
107 }
108 
109 /* to share a qh (cpu threads, or hc) */
110 static inline struct ehci_qh *qh_get (struct ehci_qh *qh)
111 {
112 	kref_get(&qh->kref);
113 	return qh;
114 }
115 
116 static inline void qh_put (struct ehci_qh *qh)
117 {
118 	kref_put(&qh->kref, qh_destroy);
119 }
120 
121 /*-------------------------------------------------------------------------*/
122 
123 /* The queue heads and transfer descriptors are managed from pools tied
124  * to each of the "per device" structures.
125  * This is the initialisation and cleanup code.
126  */
127 
128 static void ehci_mem_cleanup (struct ehci_hcd *ehci)
129 {
130 	if (ehci->async)
131 		qh_put (ehci->async);
132 	ehci->async = NULL;
133 
134 	/* DMA consistent memory and pools */
135 	if (ehci->qtd_pool)
136 		dma_pool_destroy (ehci->qtd_pool);
137 	ehci->qtd_pool = NULL;
138 
139 	if (ehci->qh_pool) {
140 		dma_pool_destroy (ehci->qh_pool);
141 		ehci->qh_pool = NULL;
142 	}
143 
144 	if (ehci->itd_pool)
145 		dma_pool_destroy (ehci->itd_pool);
146 	ehci->itd_pool = NULL;
147 
148 	if (ehci->sitd_pool)
149 		dma_pool_destroy (ehci->sitd_pool);
150 	ehci->sitd_pool = NULL;
151 
152 	if (ehci->periodic)
153 		dma_free_coherent (ehci_to_hcd(ehci)->self.controller,
154 			ehci->periodic_size * sizeof (u32),
155 			ehci->periodic, ehci->periodic_dma);
156 	ehci->periodic = NULL;
157 
158 	/* shadow periodic table */
159 	if (ehci->pshadow)
160 		kfree (ehci->pshadow);
161 	ehci->pshadow = NULL;
162 }
163 
164 /* remember to add cleanup code (above) if you add anything here */
165 static int ehci_mem_init (struct ehci_hcd *ehci, int flags)
166 {
167 	int i;
168 
169 	/* QTDs for control/bulk/intr transfers */
170 	ehci->qtd_pool = dma_pool_create ("ehci_qtd",
171 			ehci_to_hcd(ehci)->self.controller,
172 			sizeof (struct ehci_qtd),
173 			32 /* byte alignment (for hw parts) */,
174 			4096 /* can't cross 4K */);
175 	if (!ehci->qtd_pool) {
176 		goto fail;
177 	}
178 
179 	/* QHs for control/bulk/intr transfers */
180 	ehci->qh_pool = dma_pool_create ("ehci_qh",
181 			ehci_to_hcd(ehci)->self.controller,
182 			sizeof (struct ehci_qh),
183 			32 /* byte alignment (for hw parts) */,
184 			4096 /* can't cross 4K */);
185 	if (!ehci->qh_pool) {
186 		goto fail;
187 	}
188 	ehci->async = ehci_qh_alloc (ehci, flags);
189 	if (!ehci->async) {
190 		goto fail;
191 	}
192 
193 	/* ITD for high speed ISO transfers */
194 	ehci->itd_pool = dma_pool_create ("ehci_itd",
195 			ehci_to_hcd(ehci)->self.controller,
196 			sizeof (struct ehci_itd),
197 			32 /* byte alignment (for hw parts) */,
198 			4096 /* can't cross 4K */);
199 	if (!ehci->itd_pool) {
200 		goto fail;
201 	}
202 
203 	/* SITD for full/low speed split ISO transfers */
204 	ehci->sitd_pool = dma_pool_create ("ehci_sitd",
205 			ehci_to_hcd(ehci)->self.controller,
206 			sizeof (struct ehci_sitd),
207 			32 /* byte alignment (for hw parts) */,
208 			4096 /* can't cross 4K */);
209 	if (!ehci->sitd_pool) {
210 		goto fail;
211 	}
212 
213 	/* Hardware periodic table */
214 	ehci->periodic = (__le32 *)
215 		dma_alloc_coherent (ehci_to_hcd(ehci)->self.controller,
216 			ehci->periodic_size * sizeof(__le32),
217 			&ehci->periodic_dma, 0);
218 	if (ehci->periodic == NULL) {
219 		goto fail;
220 	}
221 	for (i = 0; i < ehci->periodic_size; i++)
222 		ehci->periodic [i] = EHCI_LIST_END;
223 
224 	/* software shadow of hardware table */
225 	ehci->pshadow = kmalloc (ehci->periodic_size * sizeof (void *), flags);
226 	if (ehci->pshadow == NULL) {
227 		goto fail;
228 	}
229 	memset (ehci->pshadow, 0, ehci->periodic_size * sizeof (void *));
230 
231 	return 0;
232 
233 fail:
234 	ehci_dbg (ehci, "couldn't init memory\n");
235 	ehci_mem_cleanup (ehci);
236 	return -ENOMEM;
237 }
238