KR20070060448A - Device and method for upgradin system using two step bootloader - Google Patents

Abstract

A device and a method for upgrading a system using a 2-step bootloader are provided to minimize user interference and use of a non-volatile memory when a bootloader, an OS, or an application program of an embedded system is upgraded, and perform upgrade again even if a fatal error is generated during the upgrade. The first bootloader(111) has a hardware POST(Power-On Self-Test) function and a function for setting a communication interface(120) with an external server(130) for initial system operation of the embedded system(100). The second bootloader(112) has the function for loading a kernel for executing the OS of the embedded system. If the system upgrade is needed, the first bootloader performs the system upgrade by receiving a new system image from the external server connected through the communication interface. The new system image includes at least one of the second bootloader, the kernel(113), and the application program(114).

Description

DEVICE AND METHOD FOR UPGRADIN SYSTEM USING TWO STEP BOOTLOADER}

1 is a block diagram of a system upgrade apparatus using a two-stage boot loader according to an embodiment of the present invention.

2 is a flowchart illustrating a system upgrade process using a two-stage boot loader according to an embodiment of the present invention.

* Description of the symbols for the main parts of the drawings *

100: embedded system

110: system upgrade device

111: first boot loader

112: second boot loader

113: kernel

114: Application

120; Communication device

130: external server

The present invention relates to an embedded system, and more particularly, to an apparatus and method for upgrading a boot loader or an operating system or an application for an embedded system.

In general, an embedded system refers to an electronic control system in which hardware and software of a computer are combined to perform a predetermined function. The embedded system has a built-in microprocessor to perform specialized tasks and has a unique operating system.

Such an embedded system is provided with a program called a boot loader (or also referred to as a booter). Conventionally, when upgrading a boot loader, an operating system, or a file system in an embedded system, an external server is accessed to download an image to be upgraded for the boot loader, operating system, or file system, and stored in an internal nonvolatile memory. Will be performed.

However, if you lose power or store a bad image in nonvolatile memory in the middle of this upgrade procedure, the embedded system will be disabled, and a special hardware device for recovery will be available for future upgrades. User intervention is inconvenient, such as needing to use or using complicated methods.

In order to solve this problem, Japanese Laid-Open Patent Publication No. 1999-328040, `` Memory read control method and program read control method '', can continue commercial operation even when the program becomes inoperable due to a failure during update. A method of reading a memory is disclosed. According to the preceding invention, the memory is duplicated into a first memory for storing the pre-update program of the downloaded program and a second memory for storing the post-update program, and if the update is valid, the post-update program in the second memory is executed. If the update is invalid, the stable upgrade can be performed by executing the pre-update program in the first memory. However, when the upgrade is performed using the preceding invention, since a program or a boot loader must be kept redundant, there is a problem in that a requirement of the nonvolatile memory is increased to store the duplicated program or the boot loader.

An object of the present invention for solving the above problems is to minimize the user's interference and the use of non-volatile memory when upgrading the boot loader, operating system or application, and to perform a new upgrade even if a fatal error occurs during the upgrade. The present invention provides an apparatus and method.

System upgrade apparatus using a two-stage boot loader according to the present invention for achieving the above object, the first boot loader having a hardware check (POST) for initial system operation of the embedded system and a communication interface setting function with an external server; And a second boot loader having a function of loading a kernel to execute an operating system of the embedded system, and when a system upgrade is required, the first boot loader is a new system from an external server connected through the communication interface. Receiving the image is characterized by performing a system upgrade.

In addition, the system upgrade method using a two-stage boot loader according to the present invention for achieving the above object, to perform a hardware check (POST) using the first boot loader for the initial system operation of the embedded system, and with an external server A first step of establishing a communication interface; Performing a second boot loader required to execute an operating system of the embedded system; A third step of executing a kernel and an application program; And when the system upgrade is necessary, the first boot loader includes a fourth step of receiving a new system image from an external server connected through the communication interface and performing a system upgrade.

DETAILED DESCRIPTION A detailed description of preferred embodiments of the present invention will now be described with reference to the accompanying drawings. It should be noted that the same reference numerals and the same elements among the drawings are denoted by the same reference numerals and symbols as much as possible even though they are shown in different drawings. In the following description of the present invention, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

1 is a block diagram of a system upgrade apparatus using a two-stage boot loader according to an embodiment of the present invention.

Referring to FIG. 1, the system upgrade apparatus 110 according to the present invention is configured in the embedded system 100, and includes a first boot loader 111, a second boot loader 112, and a kernel 113. And application 114.

The system upgrade apparatus according to the present invention is characterized in that the boot loaders 111 and 112 are configured in two stages, the first boot loader 111 and the second boot loader 112.

The first boot loader 111 performs a hardware check (Power-On Self-Test (POST)) for initial system operation of the embedded system 100, and also communicates with an external server 130. It is configured to have a function such as setting the communication interface required to communicate with the external server 130 by initializing the. Here, the hardware check function for initial system operation (POST) function, when the power is supplied to the embedded system 100, to check whether the keyboard, RAM, disk drive and other hardware, such as operating properly, the embedded system (100) Basic Input / Output System (BIOS) refers to a series of diagnostic test functions operated by the Basic Input / Output System (BIOS). As described above, the functions configured in the first boot loader 111 are functions that do not need to be upgraded among boot loaders such as performing a POST or setting a communication interface, and are configured with functions that a general user cannot change.

The second boot loader 112 is distinguished from the first boot loader 111 in that the second boot loader 112 is composed of functions that are expected to be upgraded, such as a function for loading a kernel 113. The second boot loader 112 performs a preparation process necessary to execute the kernel 113, loads the kernel 113 into an internal memory (not shown) of the embedded system 100, and then loads the kernel 113 into the kernel 113. You will be given control.

The kernel 113 provides various basic services to all other parts of the operating system. In general, the kernel 113 includes an interrupt handler that processes all requests that competitively request a service of the kernel 113, such as a completed input / output operation, and which programs share the processing time of the kernel 113 in any order. It includes a scheduler that decides whether to do this, and a supervisor that actually licenses the computer to each process when the schedule ends. The kernel 113 also has a memory manager that manages the address space of the operating system in memory or storage and distributes it evenly to all the peripherals and other users using the services of the kernel 113. The kernel 113 optionally mounts a file system and then executes an application program 114. The application program 114 is a program designed to directly perform a specific function to a user or another application.

The first boot loader 111 and the second boot loader 112 may be formed in a programmable nonvolatile memory in the embedded system 100.

As such, the boot loaders 111 and 112 according to the present invention may include a first boot loader 111 composed of functions that are not required to be upgraded among boot loaders, and a second boot loader configured to include upgrades among boot loaders. 112 is configured to have a two-stage boot loader, even when a fatal error such as when the power is cut off or the wrong system image is downloaded during the upgrade of the system can be stable upgrade using the first boot loader 111. Do. In addition, it is possible to save the space of the non-volatile memory in which the entire boot loader is stored than in the case of dualizing the boot loader as in the prior art.

The external server 130 maintains a system image of the second boot loader 112, the kernel 113, and the application 114, and the second boot loader 112, the kernel in the embedded system 100. If the 113 or the application 114 needs to be upgraded, a new system image necessary for upgrading the second boot loader 112, the kernel 113, or the application 114 may be displayed in the first boot loader 111. By transmitting to the system upgrade according to the invention can be made.

2 is a flowchart illustrating a system upgrade process using a two-stage boot loader according to an embodiment of the present invention.

Referring to FIG. 2, first, when power is applied to the embedded system 100, the first boot loader 111 is executed (S201). In step S201, the first boot loader 111 performs a POST process for checking a hardware state of the embedded system 100 and a procedure for initializing a communication interface with the external server 130. As such, the first boot loader 111 is executed to determine the hardware state of the embedded system 100 or the versions of the second boot loader 112, the kernel 113, and the application 114. You can check the status.

Thereafter, it is determined whether the system needs to be upgraded (S202), and when it is necessary to upgrade, the external server 130 is accessed using the communication interface (S203), and the necessary upgrade is performed (S204). In this case, the upgrade of the system is performed for the second boot loader 112, the kernel 113, and the application program 114.

In addition, if it is determined in step S202 that the system does not need to be upgraded while the first boot loader 111 is executed, the second boot loader 112 is executed (S205). The second boot loader 112 transfers control to the kernel 113 loaded in the memory after performing a task necessary to execute the kernel 113 (S206). After the kernel 113 is executed, an application program may be executed (S207). Subsequently, it is determined whether a system upgrade needs to be performed (S208), and if an upgrade is required, an external server 120 is connected (S203), and the second boot loader 112 and the kernel are connected from the external server 120. In step S204, a new image for the application program 114 is downloaded and a system upgrade is performed (S204). Otherwise, the procedure ends.

If a fatal error such as a power cut off occurs in the upgrade process of step S204 or if a wrong image is downloaded (S209), the process proceeds to the step S201 again and the first boot loader 111 is performed. Then, the upgrade procedure is repeated until the upgrade is normally performed by performing the steps S202 to S208 again.

As such, in the present invention, during the upgrade process of the step S304, even if a fatal error such as power is cut off, the first boot loader 111 region cannot be accessed by the general user and thus can always be booted again. The upgrade can be performed stably by repeating the procedure until the upgrade is normally successful using the connection with the external server 120.

The system upgrade method using the two-stage boot loader according to the present invention can be embodied as computer readable codes on a computer readable recording medium. The computer-readable recording medium includes all kinds of recording devices in which data that can be read by a computer system is stored. Examples of computer-readable recording media include ROM, RAM, CD-ROM, magnetic tape, floppy disk, optical data storage, and the like, and also include those implemented in the form of carrier waves such as transmission over the Internet. The computer readable recording medium can also be distributed over network coupled computer systems so that the computer readable code is stored and executed in a distributed fashion.

Meanwhile, in the detailed description of the present invention, specific embodiments have been described, but various modifications are possible without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined not only by the claims below, but also by those equivalent to the claims.

According to the present invention as described above, by configuring the boot loader in two stages by separating the functions that need to be upgraded and the functions that do not need to be upgraded, the power supply that can occur when upgrading the boot loader using a single boot loader Even in the event of a fatal error such as blocking, a hardware boot and initial system operation can be performed using the first boot loader irrelevant to the upgrade process, thereby providing a stable booting operation.

According to the present invention, unlike the conventional method of dualizing the boot loader by storing the same boot loader image in two nonvolatile memories, each boot loader image is divided into two functionally divided images. Since the storage in the nonvolatile memory has the advantage of improving the efficiency of the storage space of the nonvolatile memory.

Claims (7)

A first boot loader having a hardware check (POST) for initial system operation of an embedded system and a communication interface setting function with an external server; And A second boot loader having a function of loading a kernel to execute an operating system of the embedded system, When the system upgrade is necessary, the first boot loader receives a new system image from an external server connected through the communication interface and performs a system upgrade. The apparatus of claim 1, wherein the function performed by the first boot loader is configured as a function that does not require upgrade. The apparatus of claim 1, wherein the function performed by the second boot loader is configured as a function capable of performing an upgrade. The system upgrade apparatus of claim 1, wherein the system image of the upgrade includes a system image of at least one of the second boot loader, the kernel, and the application program. Performing a hardware check (POST) by using a first boot loader for initial system operation of an embedded system, and establishing a communication interface with an external server; Performing a second boot loader required to execute an operating system of the embedded system; A third step of executing a kernel and an application program; And If a system upgrade is required, the first boot loader includes a fourth step of receiving a new system image from an external server connected through the communication interface and performing a system upgrade. Way. The method of claim 5, If an error occurs while performing the system upgrade in the fourth step, performing the first to fourth steps again. The method of claim 5, wherein the upgraded system image includes a system image of at least one of a second boot loader, a kernel, and an application program.

Images