xref: /openbmc/linux/drivers/usb/host/ehci-mem.c (revision 12eb4683)
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 	if (ehci->qtd_pool)
132 		dma_pool_destroy (ehci->qtd_pool);
133 	ehci->qtd_pool = NULL;
134 
135 	if (ehci->qh_pool) {
136 		dma_pool_destroy (ehci->qh_pool);
137 		ehci->qh_pool = NULL;
138 	}
139 
140 	if (ehci->itd_pool)
141 		dma_pool_destroy (ehci->itd_pool);
142 	ehci->itd_pool = NULL;
143 
144 	if (ehci->sitd_pool)
145 		dma_pool_destroy (ehci->sitd_pool);
146 	ehci->sitd_pool = NULL;
147 
148 	if (ehci->periodic)
149 		dma_free_coherent (ehci_to_hcd(ehci)->self.controller,
150 			ehci->periodic_size * sizeof (u32),
151 			ehci->periodic, ehci->periodic_dma);
152 	ehci->periodic = NULL;
153 
154 	/* shadow periodic table */
155 	kfree(ehci->pshadow);
156 	ehci->pshadow = NULL;
157 }
158 
159 /* remember to add cleanup code (above) if you add anything here */
160 static int ehci_mem_init (struct ehci_hcd *ehci, gfp_t flags)
161 {
162 	int i;
163 
164 	/* QTDs for control/bulk/intr transfers */
165 	ehci->qtd_pool = dma_pool_create ("ehci_qtd",
166 			ehci_to_hcd(ehci)->self.controller,
167 			sizeof (struct ehci_qtd),
168 			32 /* byte alignment (for hw parts) */,
169 			4096 /* can't cross 4K */);
170 	if (!ehci->qtd_pool) {
171 		goto fail;
172 	}
173 
174 	/* QHs for control/bulk/intr transfers */
175 	ehci->qh_pool = dma_pool_create ("ehci_qh",
176 			ehci_to_hcd(ehci)->self.controller,
177 			sizeof(struct ehci_qh_hw),
178 			32 /* byte alignment (for hw parts) */,
179 			4096 /* can't cross 4K */);
180 	if (!ehci->qh_pool) {
181 		goto fail;
182 	}
183 	ehci->async = ehci_qh_alloc (ehci, flags);
184 	if (!ehci->async) {
185 		goto fail;
186 	}
187 
188 	/* ITD for high speed ISO transfers */
189 	ehci->itd_pool = dma_pool_create ("ehci_itd",
190 			ehci_to_hcd(ehci)->self.controller,
191 			sizeof (struct ehci_itd),
192 			32 /* byte alignment (for hw parts) */,
193 			4096 /* can't cross 4K */);
194 	if (!ehci->itd_pool) {
195 		goto fail;
196 	}
197 
198 	/* SITD for full/low speed split ISO transfers */
199 	ehci->sitd_pool = dma_pool_create ("ehci_sitd",
200 			ehci_to_hcd(ehci)->self.controller,
201 			sizeof (struct ehci_sitd),
202 			32 /* byte alignment (for hw parts) */,
203 			4096 /* can't cross 4K */);
204 	if (!ehci->sitd_pool) {
205 		goto fail;
206 	}
207 
208 	/* Hardware periodic table */
209 	ehci->periodic = (__le32 *)
210 		dma_alloc_coherent (ehci_to_hcd(ehci)->self.controller,
211 			ehci->periodic_size * sizeof(__le32),
212 			&ehci->periodic_dma, 0);
213 	if (ehci->periodic == NULL) {
214 		goto fail;
215 	}
216 
217 	if (ehci->use_dummy_qh) {
218 		struct ehci_qh_hw	*hw;
219 		ehci->dummy = ehci_qh_alloc(ehci, flags);
220 		if (!ehci->dummy)
221 			goto fail;
222 
223 		hw = ehci->dummy->hw;
224 		hw->hw_next = EHCI_LIST_END(ehci);
225 		hw->hw_qtd_next = EHCI_LIST_END(ehci);
226 		hw->hw_alt_next = EHCI_LIST_END(ehci);
227 		ehci->dummy->hw = hw;
228 
229 		for (i = 0; i < ehci->periodic_size; i++)
230 			ehci->periodic[i] = cpu_to_hc32(ehci,
231 					ehci->dummy->qh_dma);
232 	} else {
233 		for (i = 0; i < ehci->periodic_size; i++)
234 			ehci->periodic[i] = EHCI_LIST_END(ehci);
235 	}
236 
237 	/* software shadow of hardware table */
238 	ehci->pshadow = kcalloc(ehci->periodic_size, sizeof(void *), flags);
239 	if (ehci->pshadow != NULL)
240 		return 0;
241 
242 fail:
243 	ehci_dbg (ehci, "couldn't init memory\n");
244 	ehci_mem_cleanup (ehci);
245 	return -ENOMEM;
246 }
247