xref: /openbmc/linux/drivers/usb/host/ehci-mem.c (revision 9344dade)
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 
97 	/* dummy td enables safe urb queuing */
98 	qh->dummy = ehci_qtd_alloc (ehci, flags);
99 	if (qh->dummy == NULL) {
100 		ehci_dbg (ehci, "no dummy td\n");
101 		goto fail1;
102 	}
103 done:
104 	return qh;
105 fail1:
106 	dma_pool_free(ehci->qh_pool, qh->hw, qh->qh_dma);
107 fail:
108 	kfree(qh);
109 	return NULL;
110 }
111 
112 /*-------------------------------------------------------------------------*/
113 
114 /* The queue heads and transfer descriptors are managed from pools tied
115  * to each of the "per device" structures.
116  * This is the initialisation and cleanup code.
117  */
118 
119 static void ehci_mem_cleanup (struct ehci_hcd *ehci)
120 {
121 	if (ehci->async)
122 		qh_destroy(ehci, ehci->async);
123 	ehci->async = NULL;
124 
125 	if (ehci->dummy)
126 		qh_destroy(ehci, ehci->dummy);
127 	ehci->dummy = NULL;
128 
129 	/* DMA consistent memory and pools */
130 	if (ehci->qtd_pool)
131 		dma_pool_destroy (ehci->qtd_pool);
132 	ehci->qtd_pool = NULL;
133 
134 	if (ehci->qh_pool) {
135 		dma_pool_destroy (ehci->qh_pool);
136 		ehci->qh_pool = NULL;
137 	}
138 
139 	if (ehci->itd_pool)
140 		dma_pool_destroy (ehci->itd_pool);
141 	ehci->itd_pool = NULL;
142 
143 	if (ehci->sitd_pool)
144 		dma_pool_destroy (ehci->sitd_pool);
145 	ehci->sitd_pool = NULL;
146 
147 	if (ehci->periodic)
148 		dma_free_coherent (ehci_to_hcd(ehci)->self.controller,
149 			ehci->periodic_size * sizeof (u32),
150 			ehci->periodic, ehci->periodic_dma);
151 	ehci->periodic = NULL;
152 
153 	/* shadow periodic table */
154 	kfree(ehci->pshadow);
155 	ehci->pshadow = NULL;
156 }
157 
158 /* remember to add cleanup code (above) if you add anything here */
159 static int ehci_mem_init (struct ehci_hcd *ehci, gfp_t flags)
160 {
161 	int i;
162 
163 	/* QTDs for control/bulk/intr transfers */
164 	ehci->qtd_pool = dma_pool_create ("ehci_qtd",
165 			ehci_to_hcd(ehci)->self.controller,
166 			sizeof (struct ehci_qtd),
167 			32 /* byte alignment (for hw parts) */,
168 			4096 /* can't cross 4K */);
169 	if (!ehci->qtd_pool) {
170 		goto fail;
171 	}
172 
173 	/* QHs for control/bulk/intr transfers */
174 	ehci->qh_pool = dma_pool_create ("ehci_qh",
175 			ehci_to_hcd(ehci)->self.controller,
176 			sizeof(struct ehci_qh_hw),
177 			32 /* byte alignment (for hw parts) */,
178 			4096 /* can't cross 4K */);
179 	if (!ehci->qh_pool) {
180 		goto fail;
181 	}
182 	ehci->async = ehci_qh_alloc (ehci, flags);
183 	if (!ehci->async) {
184 		goto fail;
185 	}
186 
187 	/* ITD for high speed ISO transfers */
188 	ehci->itd_pool = dma_pool_create ("ehci_itd",
189 			ehci_to_hcd(ehci)->self.controller,
190 			sizeof (struct ehci_itd),
191 			32 /* byte alignment (for hw parts) */,
192 			4096 /* can't cross 4K */);
193 	if (!ehci->itd_pool) {
194 		goto fail;
195 	}
196 
197 	/* SITD for full/low speed split ISO transfers */
198 	ehci->sitd_pool = dma_pool_create ("ehci_sitd",
199 			ehci_to_hcd(ehci)->self.controller,
200 			sizeof (struct ehci_sitd),
201 			32 /* byte alignment (for hw parts) */,
202 			4096 /* can't cross 4K */);
203 	if (!ehci->sitd_pool) {
204 		goto fail;
205 	}
206 
207 	/* Hardware periodic table */
208 	ehci->periodic = (__le32 *)
209 		dma_alloc_coherent (ehci_to_hcd(ehci)->self.controller,
210 			ehci->periodic_size * sizeof(__le32),
211 			&ehci->periodic_dma, 0);
212 	if (ehci->periodic == NULL) {
213 		goto fail;
214 	}
215 
216 	if (ehci->use_dummy_qh) {
217 		struct ehci_qh_hw	*hw;
218 		ehci->dummy = ehci_qh_alloc(ehci, flags);
219 		if (!ehci->dummy)
220 			goto fail;
221 
222 		hw = ehci->dummy->hw;
223 		hw->hw_next = EHCI_LIST_END(ehci);
224 		hw->hw_qtd_next = EHCI_LIST_END(ehci);
225 		hw->hw_alt_next = EHCI_LIST_END(ehci);
226 		hw->hw_token &= ~QTD_STS_ACTIVE;
227 		ehci->dummy->hw = hw;
228 
229 		for (i = 0; i < ehci->periodic_size; i++)
230 			ehci->periodic[i] = ehci->dummy->qh_dma;
231 	} else {
232 		for (i = 0; i < ehci->periodic_size; i++)
233 			ehci->periodic[i] = EHCI_LIST_END(ehci);
234 	}
235 
236 	/* software shadow of hardware table */
237 	ehci->pshadow = kcalloc(ehci->periodic_size, sizeof(void *), flags);
238 	if (ehci->pshadow != NULL)
239 		return 0;
240 
241 fail:
242 	ehci_dbg (ehci, "couldn't init memory\n");
243 	ehci_mem_cleanup (ehci);
244 	return -ENOMEM;
245 }
246