include/opensbi.h

   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 };
  25
  26 /** Representation dynamic info passed by previous booting stage */
  27 struct 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