xref: /openbsd/sys/dev/cardbus/cardbus_exrom.c (revision 17df1aa7)
1 /*	$OpenBSD: cardbus_exrom.c,v 1.4 2005/09/13 18:44:38 fgsch Exp $	*/
2 /*	$NetBSD: cardbus_exrom.c,v 1.4 2000/02/03 06:47:31 thorpej Exp $	*/
3 
4 /*
5  * Copyright (c) 1999 The NetBSD Foundation, Inc.
6  * All rights reserved.
7  *
8  * This code is derived from software contributed to
9  * The NetBSD Foundation by Johan Danielsson.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  *
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  *
18  * 2. Redistributions in binary form must reproduce the above copyright
19  *    notice, this list of conditions and the following disclaimer in the
20  *    documentation and/or other materials provided with the distribution.
21  *
22  * 3. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 #include <sys/param.h>
40 #include <sys/systm.h>
41 #include <sys/queue.h>
42 #include <sys/malloc.h>
43 
44 #include <machine/bus.h>
45 
46 #include <dev/cardbus/cardbus_exrom.h>
47 
48 #if defined(CARDBUS_DEBUG)
49 #define	DPRINTF(a)	printf a
50 #else
51 #define	DPRINTF(a)
52 #endif
53 
54 #define READ_INT16(T, H, O)  \
55 	(bus_space_read_1((T), (H), (O)) | \
56 	 (bus_space_read_1((T), (H), (O) + 1) << 8))
57 
58 /*
59  *  A PCI ROM is divided into a number of images. Each image has two
60  *  data structures, a header located at the start of the image, and a
61  *  `data structure' at some offset into it.
62  *
63  *  The header is a 26 byte structure:
64  *
65  *  Offset	Length	Description
66  *  0x00	   1	signature byte 1 (0x55)
67  *  0x01	   1	signature byte 2 (0xAA)
68  *  0x02	  22	processor architecture data
69  *  0x18	   2	pointer to the data structure
70  *
71  *  The data structure is a 24 byte structure:
72  *
73  *  Offset	Length	Description
74  *  0x00	   4	signature (PCIR)
75  *  0x04	   2	vendor id
76  *  0x06	   2	device id
77  *  0x08	   2	reserved
78  *  0x0A	   2	data structure length
79  *  0x0C	   1	data structure revision (0)
80  *  0x0D	   3	class code
81  *  0x10	   2	image length (in 512 byte blocks)
82  *  0x12	   2	code revision level
83  *  0x14	   1	code type
84  *  0x15	   1	indicator (bit 7 indicates final image)
85  *  0x16	   2	reserved
86  *
87  */
88 
89 /*
90  *  Scan through a PCI expansion ROM, and create subregions for each
91  *  ROM image. This function assumes that the ROM is mapped at
92  *  (tag,handle), and that the expansion ROM address decoder is
93  *  enabled. The PCI specification requires that no other BAR should
94  *  be accessed while the ROM is enabled, so interrupts should be
95  *  disabled.
96  *
97  * XXX This routine is way too pessimistic and returns as soon as it encounters
98  * a problem, although not being able to malloc or read a particular image
99  * may not prevent further images from being read successfully.
100  */
101 int
102 cardbus_read_exrom(bus_space_tag_t romt, bus_space_handle_t romh,
103     struct cardbus_rom_image_head *head)
104 {
105 	size_t addr = 0; /* offset of current rom image */
106 	size_t dataptr;
107 	unsigned int rom_image = 0;
108 	size_t image_size;
109 	struct cardbus_rom_image *image;
110 	u_int16_t val;
111 
112 	SIMPLEQ_INIT(head);
113 	do {
114 		val = READ_INT16(romt, romh, addr + CARDBUS_EXROM_SIGNATURE);
115 		if (val != 0xaa55) {
116 			DPRINTF(("%s: bad header signature in ROM image "
117 			    "%u: 0x%04x\n", __func__, rom_image, val));
118 			return (1);
119 		}
120 		dataptr = addr + READ_INT16(romt, romh,
121 		    addr + CARDBUS_EXROM_DATA_PTR);
122 
123 		/* get the ROM image size, in blocks */
124 		image_size = READ_INT16(romt, romh,
125 		    dataptr + CARDBUS_EXROM_DATA_IMAGE_LENGTH);
126 		/* XXX
127 		 * Some ROMs seem to have this as zero, can we assume
128 		 * this means 1 block?
129 		 */
130 		if (image_size == 0)
131 			image_size = 1;
132 		image_size <<= 9;
133 
134 		image = malloc(sizeof(*image), M_DEVBUF, M_NOWAIT);
135 		if (image == NULL) {
136 			DPRINTF(("%s: out of memory\n", __func__));
137 			return (1);
138 		}
139 		image->rom_image = rom_image;
140 		image->image_size = image_size;
141 		image->romt = romt;
142 		if (bus_space_subregion(romt, romh, addr,
143 		    image_size, &image->romh)) {
144 			DPRINTF(("%s: bus_space_subregion failed", __func__));
145 			free(image, M_DEVBUF);
146 			return (1);
147 		}
148 		SIMPLEQ_INSERT_TAIL(head, image, next);
149 		addr += image_size;
150 		rom_image++;
151 	} while ((bus_space_read_1(romt, romh,
152 	    dataptr + CARDBUS_EXROM_DATA_INDICATOR) & 0x80) == 0);
153 
154 	return (0);
155 }
156