BootMap

概述

BootMap 为 SDK 启动过程提供 boot map image 配置相关功能。

底层存储

bootmap 通过调用 bootmap 相关 API 来获取已经更新 bootmap 中的 image 信息。bootmap 中存储了所有 image 的起始位置，长度，类型等信息

备注

bootmap 本身采用乒乓算法的存储方式，所以有掉电保护的功能，对于固定大小的 flash，bootmap 本身的存储位置是固定的，存储大小目前固定使用 8K, 两个 flash sector, 一般在 flash 倒数第二，第三个 sector

存储结构

当前，我们假设 flash 扇区大小为 4096 字节，

bootmap 结构如下图所示，括号内数字表示该部分的大小（以字节为单位）。

+----------------------+--------------+--------------+-------------+
|       index (4)      | image. no.(1)| boot type(1) |  Unused (2) |   页头部 (8)
+----------+-----------+-------+--------+---------+----------------+
| type (1) | Unused (3)| lma(4)| vma(4) |  len(4) | area len(4)    |   image0 信息 (20)
+------------------------------------------------------------------+
| type (1) | Unused (3)| lma(4)| vma(4) |  len(4) | area len(4)    |   image1 信息 (20)
+------------------------------------------------------------------+
| type (1) | Unused (3)| lma(4)| vma(4) |  len(4) | area len(4)    |   image2 信息 (20)
|+-----------------------------------------------------------------+
/                                                                  /
/                                                                  /
+------------------------------------------------------------------+
|                       image* information (20)                    |   image n 信息 (20)
+------------------------------------------------------------------+
|                       CRC32(4)                                   |   bootmap 校验 (4)
+------------------------------------------------------------------+

该结构存储在 bootmap 区域，每次更新后 index 减小 1，存入乒乓的另一个区域，每次取 index 小的值为最新的信息

API 介绍

This section introduces the BOOTMAP module's enum, structure, functions and how to use this component.

Defines

BOOTMAP_MAGIC: BOOTMAP header MAIGC, string WqBM.

WQ_IMAGE_MAGIC: Image header MAIGC.

BOOT_SECTION_OTA: Boot from OTA section, reserved.

BOOT_SECTION_TRY: Test boot from default section, reserved.

BOOT_SECTION_SBL: Boot from SBL section, reserved.

BOOT_SECTION_STANDARD: Boot from STANDARD section, reserved.

Enums

enum WQ_IMAGE_TYPE

Values:

enumerator IMAGE_TYPE_ROM: Image ROM type, don't need use now

enumerator IMAGE_TYPE_PBL: Image PBL type, deprecatped

enumerator IMAGE_TYPE_SYSDATA: Image SYSDATA type

enumerator IMAGE_TYPE_OTA: Image OTA type, used for upgrade firmware

enumerator IMAGE_TYPE_KV: Image KV type，for saving key-value information

enumerator IMAGE_TYPE_BOOTMAP: Image bootmap type itself，flash partion information

enumerator IMAGE_TYPE_CALDATA: Image caculate type, storage calibration information

enumerator IMAGE_TYPE_SBL0: Image SBL type, second bootloader

enumerator IMAGE_TYPE_SBL1: deprecatped

enumerator IMAGE_TYPE_RECOVER: Image recover type, used for recover firmware

enumerator IMAGE_TYPE_MAX

enum [anonymous]

Values:

enumerator WQ_BOOT_MODE_NORMAL: Normal boot mode

enumerator WQ_BOOT_MODE_OTA: OTA boot mode, will decompress ota firmware to running partion

enumerator WQ_BOOT_MODE_UNKONWN

Functions

WQ_RET bootmap_get_valid_map(bootmap_t *boot_map)

This function is to get bootmap's vaildity.

参数:

boot_map -- is boot map

返回:

WQ_RET_OK success.
WQ_RET_INVALID param error.
WQ_RET_NOT_EXIST no valid bootmap found.

WQ_RET bootmap_get_image(bootmap_image_t *image, uint8_t id)

This function is to get boot map's image.

参数:

image -- is bootmap's image
id -- is image id

返回:

WQ_RET_OK success.
WQ_RET_INVALID param error.
WQ_RET_NOT_EXIST no valid bootmap or image found.

WQ_RET bootmap_get_boot_type(uint8_t *boot_type)

This function is to get boot map's type.

返回:

WQ_RET_OK success.
WQ_RET_NOT_EXIST no valid bootmap found.

WQ_RET bootmap_set_boot_type(uint8_t boot_type)

This function is to set boot map's boot type.

参数:

boot_type -- is boot map's bppt type

返回:

WQ_RET_OK success.
WQ_RET_FAIL bootmap write fail.
WQ_RET_NOSUPP unsupport boot type
WQ_RET_NOT_EXIST no valid bootmap found.

struct bootmap_image_t

#include <bootmap.h>

Boot map image information.

Public Members

uint8_t image_type: Image ID

uint8_t reserved[3]: reserved

uint32_t code_lma: Flash offset start from 0

uint32_t code_vma: Image '_start' address

uint32_t code_length: Image true size

uint32_t code_area_size: Image Flash section size

struct bootmap_t

#include <bootmap.h>

Boot map main header.

Public Members

uint32_t index: index for header using

uint8_t image_num: total images number

uint8_t boot_type: boot type

uint8_t reserved[2]: reserved

struct wq_image_header_t

#include <bootmap.h>

Flash image header.

Public Members

uint32_t guard: Magic for image header check

uint32_t length: Image size except this header

uint32_t version: Image version

uint32_t start: Image '_start' address

uint32_t crc: Image crc except header

uint8_t tlv_count: Number of image tlv

uint8_t reserved0[3]: reserved

uint32_t stack: main stack address of th image

uint8_t reserved1[4]: reserved