CN104899091B - A kind of intelligence embedded device multiple operating system switching method - Google Patents

Abstract

The invention discloses a method for selectively starting multiple operating systems in an intelligent embedded device. Firstly, the memory is divided into multiple operating system partitions for the user, and an EEPROM flag bit operation function is added to U-Boot, and the operating system is written for each operating system. Load the startup function, set the operating system startup menu in the QT environment, select an operating system to start in the operating system startup menu, U-Boot calls the EEPROM flag bit operation function to read the flag bit of the operating system, and calls the corresponding flag bit The loading and starting function of the operating system starts the operating system. In the present invention, the switching management system is independent of U-Boot, which makes up for the shortcoming that U-Boot cannot manage hardware in an all-round way, and can provide more comprehensive interactive functions to facilitate function expansion.

Description

A method for switching between multiple operating systems of an intelligent embedded device

technical field

The invention relates to a method for switching multiple operating systems of an intelligent embedded device, belonging to the technical field of computer systems.

Background technique

Smart embedded devices such as smartphones and tablet computers have gained rapid popularity due to their thinness and portability. Usually, a smart embedded device can only run one type of operating system, and the function of each operating system is different. For example, Android and iOS mainly focus on entertainment, while Windows is more suitable for office work. In order to realize multi-type operating systems running on smart embedded devices, the industry usually adopts a method of adding a user selection menu in the boot program to obtain user selection parameters and selectively start the operating system. The boot loader is a simple program responsible for booting the operating system before the operating system is started. The multi-operating system switching scheme based on this program is restricted by the boot loader, and its scalability and manageability are very limited.

Contents of the invention

In order to solve the deficiencies of the prior art, the present invention provides a multi-operating system switching method for an intelligent embedded device, which solves the problem of poor scalability and manageability of the traditional multi-operating system switching scheme developed based on a boot loader.

The technical scheme that the present invention adopts for solving its technical problem is: provide a kind of intelligent embedded device multi-operating system switching method, comprise the following steps:

Step 1: Divide the memory partition and memory address into U-Boot partition and system partition in turn, store the image files of each operating system in the system partition in turn, and set a safety interval between the image files of each operating system, according to each operation The storage address of the image file of system sets up system image file partition table, according to this system image file partition table in U-Boot partition, set up address mapping macro definition respectively for each operating system; Described address mapping macro definition comprises NandFlash address OS_ADDR, mirror image File size OS_LEN, memory address OS_RAM_ADDR and jump address OS_RAM_BOOT_OFF of the image file bit;

Step 2: Add the EEPROM flag bit operation function in the U-Boot partition, and define the flag bits of each operating system and switch management system flag bits;

Step 3: Add the loading and starting functions of each operating system in the U-Boot partition. Each loading and starting function is used to load the image file at the Nand Flash address into the memory address OS_RAM_ADDR, and jump to the memory address OS_RAM_ADDR to start the operating system kernel;

Step 4: the operating system startup menu is set in the QT environment, and the operating system startup menu is used to select different operating systems;

Step 5: Select an operating system to start in the operating system startup menu, U-Boot calls the EEPROM flag bit operation function to read the flag bit of the operating system, calls the load and start function of the operating system corresponding to the flag bit, and starts the operating system .

In step 5, before starting the operating system, call the EEPROM flag bit operation function, and rewrite the flag bit as a switch management system flag bit.

The beneficial effect that the present invention has based on its technical scheme is:

(1) The present invention uses the switching management system to perform unified partitioning and guiding operations on the multi-type operating systems of intelligent embedded devices according to the startup logic, so that the method can conveniently complete the switching of multi-type operating systems;

(2) the present invention stores the image files of each operating system in the system partition of the memory successively and sets up a safety interval, sets up the system image file partition table according to the storage address of the image files of each operating system, and in the U-Boot partition according to the system The mirror file partition table establishes address mapping macro definitions for each operating system, and adds loading and starting functions for each operating system, and defines the flag bits corresponding to each operating system, which can reduce the failure rate in the traditional "flash" operation process and ensure The stability of multi-type operating system switching;

(3) The present invention sets the operating system startup menu in the QT environment, can provide a more humanized interactive interface and a switching system with strong scalability, and makes up for the shortcomings of weak interactive experience and poor scalability of the selection menu developed based on the boot loader.

Description of drawings

Fig. 1 is a schematic structural diagram of a system for realizing the method of the present invention.

Figure 2 is a flow chart of the method of the present invention.

FIG. 3 is a memory address partition table according to an embodiment of the present invention.

FIG. 4 is a schematic diagram of an interface of an operating system startup menu.

Detailed ways

The present invention will be further described below in conjunction with drawings and embodiments.

The present invention provides a method for switching multiple operating systems of an intelligent embedded device, referring to Fig. 2, comprising the following steps:

Step 1: Divide the memory partition and memory address into U-Boot partition and system partition in turn, store the image files of each operating system in the system partition in turn, and set a safety interval between the image files of each operating system, according to each operation The storage address of the image file of system sets up system image file partition table, according to this system image file partition table in U-Boot partition, set up address mapping macro definition respectively for each operating system; Described address mapping macro definition comprises NandFlash address OS_ADDR, mirror image File size OS_LEN, memory address OS_RAM_ADDR and jump address OS_RAM_BOOT_OFF of the image file bit;

Step 2: Add the EEPROM flag bit operation function in the U-Boot partition, and define the flag bits of each operating system and switch management system flag bits;

Step 3: Add the loading and starting functions of each operating system in the U-Boot partition. Each loading and starting function is used to load the image file at the Nand Flash address into the memory address OS_RAM_ADDR, and jump to the memory address OS_RAM_ADDR to start the operating system kernel;

Step 4: the operating system startup menu is set in the QT environment, and the operating system startup menu is used to select different operating systems;

Step 5: Select an operating system to start in the operating system startup menu, U-Boot calls the EEPROM flag bit operation function to read the flag bit of the operating system, calls the load and start function of the operating system corresponding to the flag bit, and starts the operating system .

In step 5, before starting the operating system, call the EEPROM flag bit operation function, and rewrite the flag bit as a switch management system flag bit.

The method for switching multiple operating systems of an intelligent embedded device according to the present invention can be applied to a Linux-based intelligent embedded device as shown in FIG. 1 . The hardware configuration of the intelligent embedded device is: FriendlyARM Company Mini6410 development board (Samsung S3C6410 processor, ARM1176JZF-S core, main frequency 533MHz/667MHz, 1GB Nand Flash memory, 256B IIC interface EEPROM memory)

Intelligent embedded device software configuration:

Linux QT (kernel version: 2.6.38, file system uses VFS), Android 2.3.4 (file system uses VFS), Windows CE 6.0, U-Boot 1.1.5.

The first step is to partition the memory. As shown in Figure 3, the 256KB storage area starting from Nand Flash address 0 stores the U-Boot program. After the U-Boot partition, the storage space is the system partition, which stores Windows CE, switching Management system, Linux, Android system kernel and file system image files, storage order is not strictly required. Establish the system image file partition table according to the storage address of the image file of each operating system, and establish the address mapping macro definition for each operating system in the U-Boot partition according to the system image file partition table. The address mapping macro definition of each type of operating system mainly includes : Nand Flash address OS_ADDR, image file size OS_LEN, image file bit memory address OS_RAM_ADDR and jump address OS_RAM_BOOT_OFF.

The second step is to write EEPROM operation functions in the U-Boot partition, including: first, open the source code include/configs/mini6410.hIIC interface driver macro definition: CFG_CMD_I2C; second, add EEPROM memory macro definition CFG_I2C_EEPROM_ADDR address 0x50; After the above modification, the EEPROM operation functions eeprom_read(dev_addr,off,os_flag,cnt) and eeprom_write(dev_addr,off,os_flag,cnt) can be used. Define the flag bits of each operating system. The flag bits occupy one byte, where 0x00 corresponds to the switching management system, 0x01 corresponds to Windows CE, 0x02 corresponds to the Linux QT system, and 0x03 corresponds to the Android system. The flag bits are stored in the first byte of the EEPROM memory.

Step 3: Add each operating system loading and starting function in U-Boot. Each loading and starting function will load the image file into the OS_RAM_ADDR memory operating address according to the Nand Flash address defined in the first step by calling the U-Boot loading command, and jump to Go to memory address OS_RAM_ADDR to start the operating system kernel.

Among them, the WindowsCE loading and starting function is void boot_wince (int exe_flag), and exe_flag is the starting flag bit, which determines whether to execute the starting action. The loading and starting of the operating system are realized by executing the char set_wince_bootcmd[] string definition command, "nand read.i" MK_STR( WINCE_RAM_ADDR)""MK_STR(WINCE_ADDR)""MK_STR(WINCE_LEN)";"By "bootm"MK_STR(WINCE_RAM_BOOT_OFF)";"Command U-Boot to jump to the Windows CE kernel entry to start the operating system.

The Android startup function is void boot_android(int exe_flag). Before starting Android, you need to set environment variables through char set_android_bootargs[], including specifying the VFS file system type, console interface, and LCD type. After configuration, use char set_android_bootcmd[] Define the Android startup action, the Linux startup function void boot_linux(int exe_flag), the switch management system startup function viodboot_manageos(int exe_flag) are basically consistent with the Android startup function.

The 4th step, set system startup menu in QT environment, as shown in Figure 4 is the interface schematic diagram of system startup menu, described system startup menu provides Windows CE, Linux QT and Android three example operating system selection buttons for the user, the user can After touching the LCD to directly select and the user selects the instance operating system, the EEPROM flag is rewritten to the corresponding operating system, the device restarts, and U-Boot boots to start the instance operating system.

The fifth step is to select an operating system in the operating system boot menu to start, and U-Boot executes the loading and starting function MyBootOS() including the startup logic, wherein the MyBootOS() function passes the eeprom_read(dev_addr,off,os_flag,cnt) function Obtain the flag bit, call the switch statement, and execute the corresponding operating system startup function according to the operating system mapping relationship set in the second step. When the flag bit is 0x00, 0x01, 0x02, and 0x03, execute boot_manageos(1) and boot_wince(1) respectively , boot_linux(1) and boot_android(1) functions. Before executing the function, call the eeprom_write(dev_addr,off,os_flag,cnt) function to set the flag position to 0x00, so that the system boot menu will be launched after the device is restarted.

Claims (2)

1. a kind of intelligence embedded device multiple operating system switching method, it is characterised in that include the following steps：

Step 1：By memory partition, storage address is in turn divided into U-Boot subregion and system partitioning, by each operating system Image file be successively stored in system partitioning, and between the image file of each operating system be equipped with personal distance, according to each behaviour The storage address for making the image file of system establishes system image partitions of file table, according to the system image partitions of file table in U- It is that each operating system establishes address of cache macrodefinition respectively in Boot subregion；The address of cache macrodefinition includes Nand Flash Address OS_ADDR, image file size OS_LEN, image file position memory address OS_RAM_ADDR and jump address OS_ RAM_BOOT_OFF；

Step 2：In U-Boot subregion add EEPROM flag bit handling function, and define each operating system flag bit and Handover management system sign position；

Step 3：Add the load run function of each operating system respectively in U-Boot subregion, each run function that loads is used for Image file at the address Nand Flash is loaded onto memory address OS_RAM_ADDR, and jumps to memory address OS_ RAM_ADDR start-up operation system kernel；

Step 4：Os starting menu is set in QT environment, the os starting menu is for selecting different operations System；

Step 5：An operating system is selected to start in os starting menu, U-Boot calls EEPROM flag bit behaviour The flag bit that the operating system is read as function calls the load run function of the corresponding operating system of the flag bit, starting behaviour Make system.

2. intelligence embedded device multiple operating system switching method according to claim 1, it is characterised in that：In step 5, Before start-up operation system, EEPROM flag bit handling function is called, flag bit is rewritten as handover management system sign position.