1 /*
2  * Copyright 2012 Red Hat Inc.
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice shall be included in
12  * all copies or substantial portions of the Software.
13  *
14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
17  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
18  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20  * OTHER DEALINGS IN THE SOFTWARE.
21  *
22  * Authors: Ben Skeggs
23  */
24 #include <subdev/bios.h>
25 #include <subdev/bios/bit.h>
26 
27 int
28 bit_entry(struct nvkm_bios *bios, u8 id, struct bit_entry *bit)
29 {
30 	if (likely(bios->bit_offset)) {
31 		u8  entries = nv_ro08(bios, bios->bit_offset + 10);
32 		u32 entry   = bios->bit_offset + 12;
33 		while (entries--) {
34 			if (nv_ro08(bios, entry + 0) == id) {
35 				bit->id      = nv_ro08(bios, entry + 0);
36 				bit->version = nv_ro08(bios, entry + 1);
37 				bit->length  = nv_ro16(bios, entry + 2);
38 				bit->offset  = nv_ro16(bios, entry + 4);
39 				return 0;
40 			}
41 
42 			entry += nv_ro08(bios, bios->bit_offset + 9);
43 		}
44 
45 		return -ENOENT;
46 	}
47 
48 	return -EINVAL;
49 }
50