1/* SPDX-License-Identifier: BSD-2-Clause */
2/*
3 * Copyright (c) 2019 Western Digital Corporation or its affiliates.
4 *
5 * Based on include/sbi/{fw_dynamic.h,sbi_scratch.h} from the OpenSBI project.
6 */
7#ifndef OPENSBI_H
8#define OPENSBI_H
9
10/** Expected value of info magic ('OSBI' ascii string in hex) */
11#define FW_DYNAMIC_INFO_MAGIC_VALUE		0x4942534f
12
13/** Maximum supported info version */
14#define FW_DYNAMIC_INFO_VERSION			0x2
15
16/** Possible next mode values */
17#define FW_DYNAMIC_INFO_NEXT_MODE_U		0x0
18#define FW_DYNAMIC_INFO_NEXT_MODE_S		0x1
19#define FW_DYNAMIC_INFO_NEXT_MODE_M		0x3
20
21enum sbi_scratch_options {
22	/** Disable prints during boot */
23	SBI_SCRATCH_NO_BOOT_PRINTS = (1 << 0),
24};
25
26/** Representation dynamic info passed by previous booting stage */
27struct fw_dynamic_info {
28	/** Info magic */
29	unsigned long magic;
30	/** Info version */
31	unsigned long version;
32	/** Next booting stage address */
33	unsigned long next_addr;
34	/** Next booting stage mode */
35	unsigned long next_mode;
36	/** Options for OpenSBI library */
37	unsigned long options;
38	/**
39	 * Preferred boot HART id
40	 *
41	 * It is possible that the previous booting stage uses same link
42	 * address as the FW_DYNAMIC firmware. In this case, the relocation
43	 * lottery mechanism can potentially overwrite the previous booting
44	 * stage while other HARTs are still running in the previous booting
45	 * stage leading to boot-time crash. To avoid this boot-time crash,
46	 * the previous booting stage can specify last HART that will jump
47	 * to the FW_DYNAMIC firmware as the preferred boot HART.
48	 *
49	 * To avoid specifying a preferred boot HART, the previous booting
50	 * stage can set it to -1UL which will force the FW_DYNAMIC firmware
51	 * to use the relocation lottery mechanism.
52	 */
53	unsigned long boot_hart;
54} __packed;
55
56#endif
57