xref: /linux/drivers/usb/host/ehci-mem.c (revision 6f52b16c5b29b89d92c0e7236f4655dc8491ad70)
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 "register" data (e.g. PCI or SOC), 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_hcd *ehci, struct ehci_qtd *qtd,
39 				  dma_addr_t dma)
40 {
41 	memset (qtd, 0, sizeof *qtd);
42 	qtd->qtd_dma = dma;
43 	qtd->hw_token = cpu_to_hc32(ehci, QTD_STS_HALT);
44 	qtd->hw_next = EHCI_LIST_END(ehci);
45 	qtd->hw_alt_next = EHCI_LIST_END(ehci);
46 	INIT_LIST_HEAD (&qtd->qtd_list);
47 }
48 
49 static struct ehci_qtd *ehci_qtd_alloc (struct ehci_hcd *ehci, gfp_t flags)
50 {
51 	struct ehci_qtd		*qtd;
52 	dma_addr_t		dma;
53 
54 	qtd = dma_pool_alloc (ehci->qtd_pool, flags, &dma);
55 	if (qtd != NULL) {
56 		ehci_qtd_init(ehci, qtd, dma);
57 	}
58 	return qtd;
59 }
60 
61 static inline void ehci_qtd_free (struct ehci_hcd *ehci, struct ehci_qtd *qtd)
62 {
63 	dma_pool_free (ehci->qtd_pool, qtd, qtd->qtd_dma);
64 }
65 
66 
67 static void qh_destroy(struct ehci_hcd *ehci, struct ehci_qh *qh)
68 {
69 	/* clean qtds first, and know this is not linked */
70 	if (!list_empty (&qh->qtd_list) || qh->qh_next.ptr) {
71 		ehci_dbg (ehci, "unused qh not empty!\n");
72 		BUG ();
73 	}
74 	if (qh->dummy)
75 		ehci_qtd_free (ehci, qh->dummy);
76 	dma_pool_free(ehci->qh_pool, qh->hw, qh->qh_dma);
77 	kfree(qh);
78 }
79 
80 static struct ehci_qh *ehci_qh_alloc (struct ehci_hcd *ehci, gfp_t flags)
81 {
82 	struct ehci_qh		*qh;
83 	dma_addr_t		dma;
84 
85 	qh = kzalloc(sizeof *qh, GFP_ATOMIC);
86 	if (!qh)
87 		goto done;
88 	qh->hw = (struct ehci_qh_hw *)
89 		dma_pool_alloc(ehci->qh_pool, flags, &dma);
90 	if (!qh->hw)
91 		goto fail;
92 	memset(qh->hw, 0, sizeof *qh->hw);
93 	qh->qh_dma = dma;
94 	// INIT_LIST_HEAD (&qh->qh_list);
95 	INIT_LIST_HEAD (&qh->qtd_list);
96 	INIT_LIST_HEAD(&qh->unlink_node);
97 
98 	/* dummy td enables safe urb queuing */
99 	qh->dummy = ehci_qtd_alloc (ehci, flags);
100 	if (qh->dummy == NULL) {
101 		ehci_dbg (ehci, "no dummy td\n");
102 		goto fail1;
103 	}
104 done:
105 	return qh;
106 fail1:
107 	dma_pool_free(ehci->qh_pool, qh->hw, qh->qh_dma);
108 fail:
109 	kfree(qh);
110 	return NULL;
111 }
112 
113 /*-------------------------------------------------------------------------*/
114 
115 /* The queue heads and transfer descriptors are managed from pools tied
116  * to each of the "per device" structures.
117  * This is the initialisation and cleanup code.
118  */
119 
120 static void ehci_mem_cleanup (struct ehci_hcd *ehci)
121 {
122 	if (ehci->async)
123 		qh_destroy(ehci, ehci->async);
124 	ehci->async = NULL;
125 
126 	if (ehci->dummy)
127 		qh_destroy(ehci, ehci->dummy);
128 	ehci->dummy = NULL;
129 
130 	/* DMA consistent memory and pools */
131 	dma_pool_destroy(ehci->qtd_pool);
132 	ehci->qtd_pool = NULL;
133 	dma_pool_destroy(ehci->qh_pool);
134 	ehci->qh_pool = NULL;
135 	dma_pool_destroy(ehci->itd_pool);
136 	ehci->itd_pool = NULL;
137 	dma_pool_destroy(ehci->sitd_pool);
138 	ehci->sitd_pool = NULL;
139 
140 	if (ehci->periodic)
141 		dma_free_coherent(ehci_to_hcd(ehci)->self.sysdev,
142 			ehci->periodic_size * sizeof (u32),
143 			ehci->periodic, ehci->periodic_dma);
144 	ehci->periodic = NULL;
145 
146 	/* shadow periodic table */
147 	kfree(ehci->pshadow);
148 	ehci->pshadow = NULL;
149 }
150 
151 /* remember to add cleanup code (above) if you add anything here */
152 static int ehci_mem_init (struct ehci_hcd *ehci, gfp_t flags)
153 {
154 	int i;
155 
156 	/* QTDs for control/bulk/intr transfers */
157 	ehci->qtd_pool = dma_pool_create ("ehci_qtd",
158 			ehci_to_hcd(ehci)->self.sysdev,
159 			sizeof (struct ehci_qtd),
160 			32 /* byte alignment (for hw parts) */,
161 			4096 /* can't cross 4K */);
162 	if (!ehci->qtd_pool) {
163 		goto fail;
164 	}
165 
166 	/* QHs for control/bulk/intr transfers */
167 	ehci->qh_pool = dma_pool_create ("ehci_qh",
168 			ehci_to_hcd(ehci)->self.sysdev,
169 			sizeof(struct ehci_qh_hw),
170 			32 /* byte alignment (for hw parts) */,
171 			4096 /* can't cross 4K */);
172 	if (!ehci->qh_pool) {
173 		goto fail;
174 	}
175 	ehci->async = ehci_qh_alloc (ehci, flags);
176 	if (!ehci->async) {
177 		goto fail;
178 	}
179 
180 	/* ITD for high speed ISO transfers */
181 	ehci->itd_pool = dma_pool_create ("ehci_itd",
182 			ehci_to_hcd(ehci)->self.sysdev,
183 			sizeof (struct ehci_itd),
184 			32 /* byte alignment (for hw parts) */,
185 			4096 /* can't cross 4K */);
186 	if (!ehci->itd_pool) {
187 		goto fail;
188 	}
189 
190 	/* SITD for full/low speed split ISO transfers */
191 	ehci->sitd_pool = dma_pool_create ("ehci_sitd",
192 			ehci_to_hcd(ehci)->self.sysdev,
193 			sizeof (struct ehci_sitd),
194 			32 /* byte alignment (for hw parts) */,
195 			4096 /* can't cross 4K */);
196 	if (!ehci->sitd_pool) {
197 		goto fail;
198 	}
199 
200 	/* Hardware periodic table */
201 	ehci->periodic = (__le32 *)
202 		dma_alloc_coherent(ehci_to_hcd(ehci)->self.sysdev,
203 			ehci->periodic_size * sizeof(__le32),
204 			&ehci->periodic_dma, flags);
205 	if (ehci->periodic == NULL) {
206 		goto fail;
207 	}
208 
209 	if (ehci->use_dummy_qh) {
210 		struct ehci_qh_hw	*hw;
211 		ehci->dummy = ehci_qh_alloc(ehci, flags);
212 		if (!ehci->dummy)
213 			goto fail;
214 
215 		hw = ehci->dummy->hw;
216 		hw->hw_next = EHCI_LIST_END(ehci);
217 		hw->hw_qtd_next = EHCI_LIST_END(ehci);
218 		hw->hw_alt_next = EHCI_LIST_END(ehci);
219 		ehci->dummy->hw = hw;
220 
221 		for (i = 0; i < ehci->periodic_size; i++)
222 			ehci->periodic[i] = cpu_to_hc32(ehci,
223 					ehci->dummy->qh_dma);
224 	} else {
225 		for (i = 0; i < ehci->periodic_size; i++)
226 			ehci->periodic[i] = EHCI_LIST_END(ehci);
227 	}
228 
229 	/* software shadow of hardware table */
230 	ehci->pshadow = kcalloc(ehci->periodic_size, sizeof(void *), flags);
231 	if (ehci->pshadow != NULL)
232 		return 0;
233 
234 fail:
235 	ehci_dbg (ehci, "couldn't init memory\n");
236 	ehci_mem_cleanup (ehci);
237 	return -ENOMEM;
238 }
239