xref: /openbsd-src/sys/dev/usb/usb_mem.c (revision ab0b1be78a33b04be9f7ec4a3d24ce14843759cb)
1 /*	$OpenBSD: usb_mem.c,v 1.25 2013/04/15 09:23:02 mglocker Exp $ */
2 /*	$NetBSD: usb_mem.c,v 1.26 2003/02/01 06:23:40 thorpej Exp $	*/
3 
4 /*
5  * Copyright (c) 1998 The NetBSD Foundation, Inc.
6  * All rights reserved.
7  *
8  * This code is derived from software contributed to The NetBSD Foundation
9  * by Lennart Augustsson (lennart@augustsson.net) at
10  * Carlstedt Research & Technology.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
23  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
24  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
25  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
26  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
27  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
29  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
30  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
31  * POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 /*
35  * USB DMA memory allocation.
36  * We need to allocate a lot of small (many 8 byte, some larger)
37  * memory blocks that can be used for DMA.  Using the bus_dma
38  * routines directly would incur large overheads in space and time.
39  */
40 
41 #include <sys/param.h>
42 #include <sys/systm.h>
43 #include <sys/kernel.h>
44 #include <sys/malloc.h>
45 #include <sys/queue.h>
46 #include <sys/timeout.h>
47 #include <sys/device.h>		/* for usbdivar.h */
48 #include <machine/bus.h>
49 
50 #include <dev/usb/usb.h>
51 #include <dev/usb/usbdi.h>
52 #include <dev/usb/usbdivar.h>	/* just for struct usb_dma */
53 #include <dev/usb/usb_mem.h>
54 
55 #ifdef USB_DEBUG
56 #define DPRINTF(x)	do { if (usbdebug) printf x; } while (0)
57 #define DPRINTFN(n,x)	do { if (usbdebug>(n)) printf x; } while (0)
58 extern int usbdebug;
59 #else
60 #define DPRINTF(x)
61 #define DPRINTFN(n,x)
62 #endif
63 
64 #define USB_MEM_SMALL 64
65 #define USB_MEM_CHUNKS 64
66 #define USB_MEM_BLOCK (USB_MEM_SMALL * USB_MEM_CHUNKS)
67 
68 /* This struct is overlayed on free fragments. */
69 struct usb_frag_dma {
70 	struct usb_dma_block *block;
71 	u_int offs;
72 	LIST_ENTRY(usb_frag_dma) next;
73 };
74 
75 usbd_status	usb_block_allocmem(bus_dma_tag_t, size_t, size_t,
76 		    struct usb_dma_block **);
77 void		usb_block_freemem(struct usb_dma_block *);
78 
79 LIST_HEAD(, usb_dma_block) usb_blk_freelist =
80 	LIST_HEAD_INITIALIZER(usb_blk_freelist);
81 int usb_blk_nfree = 0;
82 /* XXX should have different free list for different tags (for speed) */
83 LIST_HEAD(, usb_frag_dma) usb_frag_freelist =
84 	LIST_HEAD_INITIALIZER(usb_frag_freelist);
85 
86 usbd_status
87 usb_block_allocmem(bus_dma_tag_t tag, size_t size, size_t align,
88     struct usb_dma_block **dmap)
89 {
90 	int error;
91         struct usb_dma_block *p;
92 	int s;
93 
94 	DPRINTFN(5, ("usb_block_allocmem: size=%lu align=%lu\n",
95 		     (u_long)size, (u_long)align));
96 
97 #ifdef DIAGNOSTIC
98 	if (!curproc) {
99 		printf("usb_block_allocmem: in interrupt context, size=%lu\n",
100 		    (unsigned long) size);
101 	}
102 #endif
103 
104 	s = splusb();
105 	/* First check the free list. */
106 	for (p = LIST_FIRST(&usb_blk_freelist); p; p = LIST_NEXT(p, next)) {
107 		if (p->tag == tag && p->size >= size && p->align >= align) {
108 			LIST_REMOVE(p, next);
109 			usb_blk_nfree--;
110 			splx(s);
111 			*dmap = p;
112 			DPRINTFN(6,("usb_block_allocmem: free list size=%lu\n",
113 				    (u_long)p->size));
114 			return (USBD_NORMAL_COMPLETION);
115 		}
116 	}
117 	splx(s);
118 
119 #ifdef DIAGNOSTIC
120 	if (!curproc) {
121 		printf("usb_block_allocmem: in interrupt context, failed\n");
122 		return (USBD_NOMEM);
123 	}
124 #endif
125 
126 	DPRINTFN(6, ("usb_block_allocmem: no free\n"));
127 	p = malloc(sizeof *p, M_USB, M_NOWAIT);
128 	if (p == NULL)
129 		return (USBD_NOMEM);
130 
131 	p->tag = tag;
132 	p->size = size;
133 	p->align = align;
134 	error = bus_dmamem_alloc(tag, p->size, align, 0,
135 				 p->segs, nitems(p->segs),
136 				 &p->nsegs, BUS_DMA_NOWAIT);
137 	if (error)
138 		goto free0;
139 
140 	error = bus_dmamem_map(tag, p->segs, p->nsegs, p->size,
141 			       &p->kaddr, BUS_DMA_NOWAIT|BUS_DMA_COHERENT);
142 	if (error)
143 		goto free1;
144 
145 	error = bus_dmamap_create(tag, p->size, 1, p->size,
146 				  0, BUS_DMA_NOWAIT, &p->map);
147 	if (error)
148 		goto unmap;
149 
150 	error = bus_dmamap_load(tag, p->map, p->kaddr, p->size, NULL,
151 				BUS_DMA_NOWAIT);
152 	if (error)
153 		goto destroy;
154 
155 	*dmap = p;
156 	return (USBD_NORMAL_COMPLETION);
157 
158 destroy:
159 	bus_dmamap_destroy(tag, p->map);
160 unmap:
161 	bus_dmamem_unmap(tag, p->kaddr, p->size);
162 free1:
163 	bus_dmamem_free(tag, p->segs, p->nsegs);
164 free0:
165 	free(p, M_USB);
166 	return (USBD_NOMEM);
167 }
168 
169 #if 0
170 void
171 usb_block_real_freemem(struct usb_dma_block *p)
172 {
173 #ifdef DIAGNOSTIC
174 	if (!curproc) {
175 		printf("usb_block_real_freemem: in interrupt context\n");
176 		return;
177 	}
178 #endif
179 	bus_dmamap_unload(p->tag, p->map);
180 	bus_dmamap_destroy(p->tag, p->map);
181 	bus_dmamem_unmap(p->tag, p->kaddr, p->size);
182 	bus_dmamem_free(p->tag, p->segs, p->nsegs);
183 	free(p, M_USB);
184 }
185 #endif
186 
187 /*
188  * Do not free the memory unconditionally since we might be called
189  * from an interrupt context and that is BAD.
190  * XXX when should we really free?
191  */
192 void
193 usb_block_freemem(struct usb_dma_block *p)
194 {
195 	int s;
196 
197 	DPRINTFN(6, ("usb_block_freemem: size=%lu\n", (u_long)p->size));
198 	s = splusb();
199 	LIST_INSERT_HEAD(&usb_blk_freelist, p, next);
200 	usb_blk_nfree++;
201 	splx(s);
202 }
203 
204 usbd_status
205 usb_allocmem(struct usbd_bus *bus, size_t size, size_t align, struct usb_dma *p)
206 {
207 	bus_dma_tag_t tag = bus->dmatag;
208 	usbd_status err;
209 	struct usb_frag_dma *f;
210 	struct usb_dma_block *b;
211 	int i;
212 	int s;
213 
214 	/* If the request is large then just use a full block. */
215 	if (size > USB_MEM_SMALL || align > USB_MEM_SMALL) {
216 		DPRINTFN(1, ("usb_allocmem: large alloc %d\n", (int)size));
217 		size = (size + USB_MEM_BLOCK - 1) & ~(USB_MEM_BLOCK - 1);
218 		err = usb_block_allocmem(tag, size, align, &p->block);
219 		if (!err) {
220 			p->block->fullblock = 1;
221 			p->offs = 0;
222 		}
223 		return (err);
224 	}
225 
226 	s = splusb();
227 	/* Check for free fragments. */
228 	for (f = LIST_FIRST(&usb_frag_freelist); f; f = LIST_NEXT(f, next))
229 		if (f->block->tag == tag)
230 			break;
231 	if (f == NULL) {
232 		DPRINTFN(1, ("usb_allocmem: adding fragments\n"));
233 		err = usb_block_allocmem(tag, USB_MEM_BLOCK, USB_MEM_SMALL,&b);
234 		if (err) {
235 			splx(s);
236 			return (err);
237 		}
238 		b->fullblock = 0;
239 		for (i = 0; i < USB_MEM_BLOCK; i += USB_MEM_SMALL) {
240 			f = (struct usb_frag_dma *)(b->kaddr + i);
241 			f->block = b;
242 			f->offs = i;
243 			LIST_INSERT_HEAD(&usb_frag_freelist, f, next);
244 		}
245 		f = LIST_FIRST(&usb_frag_freelist);
246 	}
247 	p->block = f->block;
248 	p->offs = f->offs;
249 	LIST_REMOVE(f, next);
250 	splx(s);
251 	DPRINTFN(5, ("usb_allocmem: use frag=%p size=%d\n", f, (int)size));
252 	return (USBD_NORMAL_COMPLETION);
253 }
254 
255 void
256 usb_freemem(struct usbd_bus *bus, struct usb_dma *p)
257 {
258 	struct usb_frag_dma *f;
259 	int s;
260 
261 	if (p->block->fullblock) {
262 		DPRINTFN(1, ("usb_freemem: large free\n"));
263 		usb_block_freemem(p->block);
264 		return;
265 	}
266 	f = KERNADDR(p, 0);
267 	f->block = p->block;
268 	f->offs = p->offs;
269 	s = splusb();
270 	LIST_INSERT_HEAD(&usb_frag_freelist, f, next);
271 	splx(s);
272 	DPRINTFN(5, ("usb_freemem: frag=%p\n", f));
273 }
274 
275 void
276 usb_syncmem(struct usb_dma *p, bus_addr_t offset, bus_size_t len, int ops)
277 {
278 	bus_dmamap_sync(p->block->tag, p->block->map, p->offs + offset,
279 	    len, ops);
280 }
281