1 /*
2  *  skl-sst-utils.c - SKL sst utils functions
3  *
4  *  Copyright (C) 2016 Intel Corp
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as version 2, as
8  * published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it will be useful, but
11  * WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13  * General Public License for more details.
14  */
15 
16 #include <linux/firmware.h>
17 #include "skl-sst-dsp.h"
18 
19 /* FW Extended Manifest Header id = $AE1 */
20 #define SKL_EXT_MANIFEST_HEADER_MAGIC   0x31454124
21 
22 struct skl_ext_manifest_hdr {
23 	u32 id;
24 	u32 len;
25 	u16 version_major;
26 	u16 version_minor;
27 	u32 entries;
28 };
29 
30 /*
31  * some firmware binary contains some extended manifest. This needs
32  * to be stripped in that case before we load and use that image.
33  *
34  * So check for magic header, if found strip the header
35  */
36 int skl_dsp_strip_extended_manifest(struct firmware *fw)
37 {
38 	struct skl_ext_manifest_hdr *hdr;
39 
40 	/* check if fw file is greater than header we are looking */
41 	if (fw->size < sizeof(hdr)) {
42 		pr_err("%s: Firmware file small, no hdr\n", __func__);
43 		return -EINVAL;
44 	}
45 
46 	hdr = (struct skl_ext_manifest_hdr *)fw->data;
47 
48 	if (hdr->id == SKL_EXT_MANIFEST_HEADER_MAGIC) {
49 		fw->size -= hdr->len;
50 		fw->data += hdr->len;
51 	}
52 
53 	return 0;
54 }
55