xref: /openbsd/sys/dev/cardbus/cardbus_exrom.c (revision 91f110e0)
1 /*	$OpenBSD: cardbus_exrom.c,v 1.5 2013/06/20 09:52:09 mpi 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  *
23  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
24  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
25  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
26  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
27  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
28  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
29  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
30  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
31  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
32  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
33  * POSSIBILITY OF SUCH DAMAGE.
34  */
35 
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/queue.h>
39 #include <sys/malloc.h>
40 
41 #include <machine/bus.h>
42 
43 #include <dev/cardbus/cardbus_exrom.h>
44 
45 #if defined(CARDBUS_DEBUG)
46 #define	DPRINTF(a)	printf a
47 #else
48 #define	DPRINTF(a)
49 #endif
50 
51 #define READ_INT16(T, H, O)  \
52 	(bus_space_read_1((T), (H), (O)) | \
53 	 (bus_space_read_1((T), (H), (O) + 1) << 8))
54 
55 /*
56  *  A PCI ROM is divided into a number of images. Each image has two
57  *  data structures, a header located at the start of the image, and a
58  *  `data structure' at some offset into it.
59  *
60  *  The header is a 26 byte structure:
61  *
62  *  Offset	Length	Description
63  *  0x00	   1	signature byte 1 (0x55)
64  *  0x01	   1	signature byte 2 (0xAA)
65  *  0x02	  22	processor architecture data
66  *  0x18	   2	pointer to the data structure
67  *
68  *  The data structure is a 24 byte structure:
69  *
70  *  Offset	Length	Description
71  *  0x00	   4	signature (PCIR)
72  *  0x04	   2	vendor id
73  *  0x06	   2	device id
74  *  0x08	   2	reserved
75  *  0x0A	   2	data structure length
76  *  0x0C	   1	data structure revision (0)
77  *  0x0D	   3	class code
78  *  0x10	   2	image length (in 512 byte blocks)
79  *  0x12	   2	code revision level
80  *  0x14	   1	code type
81  *  0x15	   1	indicator (bit 7 indicates final image)
82  *  0x16	   2	reserved
83  *
84  */
85 
86 /*
87  *  Scan through a PCI expansion ROM, and create subregions for each
88  *  ROM image. This function assumes that the ROM is mapped at
89  *  (tag,handle), and that the expansion ROM address decoder is
90  *  enabled. The PCI specification requires that no other BAR should
91  *  be accessed while the ROM is enabled, so interrupts should be
92  *  disabled.
93  *
94  * XXX This routine is way too pessimistic and returns as soon as it encounters
95  * a problem, although not being able to malloc or read a particular image
96  * may not prevent further images from being read successfully.
97  */
98 int
99 cardbus_read_exrom(bus_space_tag_t romt, bus_space_handle_t romh,
100     struct cardbus_rom_image_head *head)
101 {
102 	size_t addr = 0; /* offset of current rom image */
103 	size_t dataptr;
104 	unsigned int rom_image = 0;
105 	size_t image_size;
106 	struct cardbus_rom_image *image;
107 	u_int16_t val;
108 
109 	SIMPLEQ_INIT(head);
110 	do {
111 		val = READ_INT16(romt, romh, addr + CARDBUS_EXROM_SIGNATURE);
112 		if (val != 0xaa55) {
113 			DPRINTF(("%s: bad header signature in ROM image "
114 			    "%u: 0x%04x\n", __func__, rom_image, val));
115 			return (1);
116 		}
117 		dataptr = addr + READ_INT16(romt, romh,
118 		    addr + CARDBUS_EXROM_DATA_PTR);
119 
120 		/* get the ROM image size, in blocks */
121 		image_size = READ_INT16(romt, romh,
122 		    dataptr + CARDBUS_EXROM_DATA_IMAGE_LENGTH);
123 		/* XXX
124 		 * Some ROMs seem to have this as zero, can we assume
125 		 * this means 1 block?
126 		 */
127 		if (image_size == 0)
128 			image_size = 1;
129 		image_size <<= 9;
130 
131 		image = malloc(sizeof(*image), M_DEVBUF, M_NOWAIT);
132 		if (image == NULL) {
133 			DPRINTF(("%s: out of memory\n", __func__));
134 			return (1);
135 		}
136 		image->rom_image = rom_image;
137 		image->image_size = image_size;
138 		image->romt = romt;
139 		if (bus_space_subregion(romt, romh, addr,
140 		    image_size, &image->romh)) {
141 			DPRINTF(("%s: bus_space_subregion failed", __func__));
142 			free(image, M_DEVBUF);
143 			return (1);
144 		}
145 		SIMPLEQ_INSERT_TAIL(head, image, next);
146 		addr += image_size;
147 		rom_image++;
148 	} while ((bus_space_read_1(romt, romh,
149 	    dataptr + CARDBUS_EXROM_DATA_INDICATOR) & 0x80) == 0);
150 
151 	return (0);
152 }
153