xref: /openbmc/qemu/include/hw/riscv/boot_opensbi.h (revision b91a0fa7)
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 
21 enum sbi_scratch_options {
22     /** Disable prints during boot */
23     SBI_SCRATCH_NO_BOOT_PRINTS = (1 << 0),
24     /** Enable runtime debug prints */
25     SBI_SCRATCH_DEBUG_PRINTS = (1 << 1),
26 };
27 
28 /** Representation dynamic info passed by previous booting stage */
29 struct fw_dynamic_info {
30     /** Info magic */
31     target_long magic;
32     /** Info version */
33     target_long version;
34     /** Next booting stage address */
35     target_long next_addr;
36     /** Next booting stage mode */
37     target_long next_mode;
38     /** Options for OpenSBI library */
39     target_long options;
40     /**
41      * Preferred boot HART id
42      *
43      * It is possible that the previous booting stage uses same link
44      * address as the FW_DYNAMIC firmware. In this case, the relocation
45      * lottery mechanism can potentially overwrite the previous booting
46      * stage while other HARTs are still running in the previous booting
47      * stage leading to boot-time crash. To avoid this boot-time crash,
48      * the previous booting stage can specify last HART that will jump
49      * to the FW_DYNAMIC firmware as the preferred boot HART.
50      *
51      * To avoid specifying a preferred boot HART, the previous booting
52      * stage can set it to -1UL which will force the FW_DYNAMIC firmware
53      * to use the relocation lottery mechanism.
54      */
55     target_long boot_hart;
56 };
57 
58 #endif
59