KR20010087868A - Method for booting operating system in Linux - Google Patents

Abstract

PURPOSE: A method for booting the LINUX operating system is provided to mount the LINUX operating system on a flash ROM, not on a floppy disk or hard disk, and to begin the booting in the LINUX by applying a 68000 series micro controller to an embedded system. CONSTITUTION: When a BLFEL(Boot Loader For Embedded Linux) program is performed, the component hardware of LOC(Linux On Chip) becomes initialized(S100). The OS(Operating System) determines if the monitor mode is operated or not(S150). When the signal, which delivers a command from a host computer, is sent to the LOC, the OS runs the monitor mode(S200). The OS checks if the flash memory is normal or not(S250). If the flash memory is not normal, the process returns to the S200 step. Otherwise, a LINUX kernel image, binary file, is downloaded from the host computer and stored to the flash memory. The OS reads and mounts the LINUX kernel image to a RAM memory(S300), and jumps to the start address of the LINUX kernel(S400).

Description

Method for booting operating system in Linux}

The present invention relates to a Linux operating system booting method, and more particularly, Linux operating which provides a function of loading and booting a Linux operating system to an embedded controller based on a 68000. It is about how to boot the system.

Recently, the market size of Linux embedded system is growing rapidly, and the battle between Windows and Linux on the operating system market of the system is intensifying. Using Linux, video telephone and CDMA (Mobile Division) type mobile phone terminal and IMT (International Mobile Telecommunication) 2000 terminal development is being made. Embedded system is a device that does not read software, which is an operating system that operates the device, from a disk like a computer, but embeds it in a chip.It is a mobile phone terminal, set-top box, palmtop, personal information device, automobile, and rice cooker. And devices incorporating chips containing software such as refrigerators. In general, the operating system is the key to how quickly and smoothly the function to be used for the purpose, Linux is considered to be ahead of Windows, and ROM (Basic Input Output System) of personal computer is operating like Windows It is responsible for validating memory after powering up, recognizing and initializing hardware, and copying the operating system to memory so that the system can be executed.

1 is a block diagram of a computer equipped with a Linux operating system according to the prior art.

In FIG. 1, a computer equipped with a Linux operating system according to the prior art is composed of a computer main body 10, a monitor 20, a keyboard 30, a CD ROM driver 40, and a floppy disk driver 50. The computer body 10 is composed of a central processing unit 11, a ROM BIOS 12, a RAM 13, a flash / hard disk 14, and an external interface 15 for interfacing with a computer component. do.

The ROM BIOS 12 is required to run the Linux operating system. The ROM BIOS 12 checks the configuration of the computer hardware when the power is turned on and checks whether the CD ROM driver 40 or the floppy disk driver 50 is installed. Check. Reads a binary file, which is a Linux kernel image, from a CD-ROM driver 40 or a floppy disk driver 50, and stores it in a flash / hard disk 14. ) Starts up, performs a hardware test, reads the Linux kernel image from the flash / hard disk (14), copies it into RAM (13), and then boots into Linux. In other words, it checks whether the OS (Operating System) is mounted on the flash / hard disk 14 and copies it to the RAM 13 area as main memory to boot the mounted OS. The flash disk of the flash / hard disk 14 described above is configured by mounting a flash ROM and a control system for implementing a file system together, and has a performance similar to that of the hard disk of the flash / hard disk 14.

However, a computer equipped with a Linux operating system according to the prior art has the following problems.

In order to install Linux, you must use embedded computer equipped with ROM BIOS and operate the computer only after complicated cabling process by installing CD ROM driver, floppy disk driver, keyboard and monitor. In addition, a flash disk or a hard disk is adopted as a memory used to store a Linux kernel image. A flash disk is a semiconductor memory in which a file system is implemented to act like a hard disk, and a separate chip for implementing a function inside a computer is provided. It is expensive compared to its capacity, and hard disks are bulky to apply to embedded systems and are vulnerable to shock and vibration.

Therefore, the present invention is to solve such a problem, the object of the present invention is applied to an embedded system using a 68000 series of microcontroller, to implement the mounting and booting of the Linux operating system floppy disk or flash / hard disk It provides a Linux operating system booting method that loads the Linux operating system into a non-volatile flash ROM, copies it into main memory, validates it, and starts booting into Linux.

1 is a block diagram of a computer equipped with a Linux operating system according to the prior art,

2 is a block diagram of an apparatus for performing a Linux operating system booting method according to the present invention;

3 is a flowchart for performing a Linux operating system booting method according to the present invention;

4 is a detailed flowchart of a Linux operating system booting method according to the present invention shown in FIG.

5 is another detailed flowchart of the Linux operating system booting method according to the present invention shown in FIG.

6 is another detailed flowchart of the Linux operating system booting method according to the present invention shown in FIG. 3;

7 is another detailed flowchart of the Linux operating system booting method according to the present invention shown in FIG.

<Explanation of symbols for the main parts of the drawings>

100: LOC 110: central processing unit

120: flash ROM 130: RAM

140: external interface 200: host computer

210: monitor 220: computer body

230: keyboard

A feature of the present invention for achieving the above object is an operating system for operating an electronic device using an embedded system equipped with Linux, comprising: a first process of initializing configuration hardware of the electronic device; A second step of determining whether to enter a monitor mode when the electronic device is initialized in the first step; A third step of executing a monitor mode when entering the monitor mode in the second step; A fourth step of determining whether the flash memory is normal when the monitor mode is not entered into the second process or the monitor mode is executed in the third process; A fifth process of returning to the third process if the flash memory is not normal in the fourth process, and if the flash memory is normal, reading a kernel image of the Linux from the flash memory and loading the RAM image into the RAM memory; And a sixth process of jumping to a start address of the kernel of the Linux when the kernel image of the Linux is mounted in the RAM memory in the fifth process.

Preferably, the first process comprises: a first step of initializing a built-in timer to initialize configuration hardware of the electronic device; A second step of initializing serial communication when the internal timer is initialized in the first step; A third step of setting an area size of the flash memory when the serial communication is initialized in the second step; A fourth step of setting an area size of the RAM memory when the area size of the flash memory is set in the third step; And a fifth step of setting an interrupt handler when an area size of the RAM memory is set in the fourth step.

Preferably, the third process includes a first step of determining whether a command is detected to execute the monitor mode; A second step of returning to the first step to receive the command if the command is not detected in the first step; A third step of reading / writing using the RAM memory, accessing a communication chip, receiving the kernel of the Linux through serial communication, and programming into the flash memory if the command is detected in the first step. ; A fourth step of receiving the command and returning to the first step when the third step is performed; And a fifth step of instructing a flash boot of the flash memory when the command is detected in the first step.

Preferably, the fifth step includes a first step of validating a flash image file of the flash memory to read a kernel image of the Linux from the flash memory and to mount the kernel image in the RAM memory; A second step of determining whether the validity of the flash image file checked in the first step is normal; A third step of performing an error report if the validity of the flash image file is not normal in the second step; And a fourth step of copying the image file of the flash memory to the block of the RAM memory when the validity of the flash image file is normal in the second step.

Preferably, the sixth step may include a first step of starting a kernel operation of the Linux to jump to a start address of the kernel of the Linux; And a second step of starting the Linux operation of the embedded system based on the flash memory when the kernel operation of the Linux is started in the first step.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. First, in adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are denoted by the same reference numerals as much as possible even if displayed on the other drawings.

2 is a block diagram of a device for performing a Linux operating system booting method according to the present invention, Figure 3 is a flow chart for performing a Linux operating system booting method according to the present invention.

2 and 3, LOC (Linux) consisting of the central processing unit 110, flash ROM 120, RAM 130 and the external interface 140 to perform the Linux operating system booting method according to the present invention. On Chip) 100, and a host computer 200 composed of a monitor 210, a computer body 220 and a keyboard 230, the LOC 100 and the host computer 200 is RS-232C communication It is connected by cable. The host computer 200 is also equipped with a terminal emulator program.

The flash ROM 120 of the LOC 100 is a chip-shaped semiconductor component, and there is no flash ROM mounted on a flash disk of the conventional flash / hard disk 14 and a control chip for implementing a file system among the chips for implementing a file system. Has

In order to mount Linux on the LOC 100 without the ROM BIOS 12 or the CD ROM driver 40 of FIG. 1, a BLoader (Boot Loader For Embeded Linux) program is used. The BLFEL program is a ROM BIOS 12. Will replace. Only after the BLFEL program is stored in the LOC 100 is it possible to mount Linux through communication. In order to mount this Linux, power is supplied to an electronic device such as the LOC 100 and the BLFEL program is executed. When the BLFEL program is executed, the configuration hardware of the LOC 100 is initialized (step S100). When the LOC 100 is initialized in step S100, it is determined whether to enter the monitor mode for executing the monitor 210 (step S150).

When a signal for transmitting a command from the host computer 200 to the LOC 100 is transmitted in step S150, the monitor enters the monitor mode and executes the monitor mode (step S200). If the monitor mode is not entered in step S150 or if the monitor mode is executed in step S200, it is determined whether the flash memory 120 of the flash ROM 120 is normal (step S250).

If the flash memory 120 of the flash ROM 120 is not normal in step S250, the process returns to step S200. If the flash memory of the flash ROM 120 is normal, the Linux kernel image, which is a binary file, is downloaded from the host computer 200 and the flash ROM is downloaded. 120 is stored in the flash memory.

After performing step S250, the kernel image of Linux stored in the flash memory 120 is read and loaded into the RAM 130 memory, which is the main memory (step S300), and the kernel of Linux is stored in the RAM 130 memory at step S300. If the image is mounted, jump to the starting address of the kernel of Linux (step S400).

4 is a detailed flowchart of a Linux operating system booting method according to the present invention shown in FIG. 3.

In FIG. 4, in order to initialize the configuration hardware of the host computer 200, which is an electronic device, an internal timer (not shown) of the host computer 200 is initialized (step S101). Initialize the serial communication via -232C (step S102). When the serial communication is initialized in step S102, the area size of the flash memory, which is the flash ROM 120, is set (step S103). When the area size of the flash memory, which is the flash ROM 120, is set, in step S103, The area size is set (step S104). If the area size of the RAM 130 memory is set in step S104, an interrupt handler is set (step S105).

5 is another detailed flowchart of the Linux operating system booting method according to the present invention shown in FIG. 3.

In FIG. 5, it is determined whether the LOC 100 detects a command transmitted from the host computer 200 to execute the monitor mode (step S201), and if it is not detected in step S201, to receive a command S201. Return to step (step S202). If an instruction is detected in step S202, the memory is read / write using the RAM 130 (step S203), a communication chip (not shown) of the host computer 200 is accessed (step S204), and serial communication is performed. The kernel of Linux is received (step S205), and the flash memory 120 is programmed to flash memory (step S206) to store the Linux kernel image.

When steps S203 to S206 are performed, the LOC 100 receives a command from the host computer 200 (step S207), and returns to step S201. Then, if the host computer 200 is restarted and the command is detected again, the Linux kernel image is read from the flash memory, which is the flash ROM 120, copied to the RAM 130 memory, and then the flash boot command is executed (step S208).

6 is another detailed flowchart of the Linux operating system booting method according to the present invention shown in FIG. 3.

In Fig. 6, in order to read the kernel image of Linux from the flash memory, which is the flash ROM 120, and to mount it in the RAM 130, the validity of the flash image file of the flash memory which is the flash ROM 120 is checked (step S301). In step S301, the validity of the flash image file checked in step S302 is determined to be normal (step S302). If the validity of the flash image file is not normal in step S302, the LOC 100 reports an error to the host computer 200 ( Step S303). If the validity of the flash image file is normal in step S302, the image file of the flash memory 120 that is the flash ROM 120 is copied to a block of the RAM 130 memory (step S304).

7 is another detailed flowchart of the Linux operating system booting method according to the present invention shown in FIG. 3.

In FIG. 7, the kernel operation of Linux is started to jump to the starting address of the kernel of Linux (step S401). When the kernel operation of Linux is started at step S401, a flash ROM ( 120, the Linux operation of the embedded system based on the flash memory is started (step S402).

As described above, 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 by the claims below and equivalents thereof.

As a result, according to the Linux operating system booting method according to the present invention the following advantages occur.

In other words, it doesn't need ROM BIOS for Linux, no peripheral device such as CD ROM driver, floppy disk driver, keyboard and monitor, and it can be manufactured in a very small size compared to the existing embedded computer. Linux can be built into a typical embedded system that is a processor application.

Claims (6)

In an operating system operating an electronic device using an embedded system equipped with Linux, A first step of initializing configuration hardware of the electronic device; A second step of determining whether to enter a monitor mode when the electronic device is initialized in the first step; A third step of executing a monitor mode when entering the monitor mode in the second step; A fourth step of determining whether the flash memory is normal when the monitor mode is not entered into the second process or the monitor mode is executed in the third process; A fifth process of returning to the third process if the flash memory is not normal in the fourth process, and if the flash memory is normal, reading a kernel image of the Linux from the flash memory and loading the RAM image into the RAM memory; And And a sixth step of jumping to a start address of the kernel of the Linux when the kernel image of the Linux is mounted in the RAM memory in the fifth step. The method of claim 1, wherein the first process is A first step of initializing a built-in timer to initialize configuration hardware of the electronic device; A second step of initializing serial communication when the internal timer is initialized in the first step; A third step of setting an area size of the flash memory when the serial communication is initialized in the second step; A fourth step of setting an area size of the RAM memory when the area size of the flash memory is set in the third step; And And a fifth step of setting an interrupt handler when the area size of the RAM memory is set in the fourth step. The method of claim 1, wherein the third process is A first step of determining whether a command is detected to execute the monitor mode; A second step of returning to the first step to receive the command if the command is not detected in the first step; A third step of reading / writing using the RAM memory, accessing a communication chip, receiving the kernel of the Linux through serial communication, and programming into the flash memory if the command is detected in the first step. ; A fourth step of receiving the command and returning to the first step when the third step is performed; And And a fifth step of instructing a flash boot of the flash memory when the command is detected in the first step. The method of claim 1, wherein the fifth process A first step of validating a flash image file of the flash memory to read a kernel image of the Linux from the flash memory and to load the kernel image into the RAM memory; A second step of determining whether the validity of the flash image file checked in the first step is normal; A third step of performing an error report if the validity of the flash image file is not normal in the second step; And And copying the image file of the flash memory into the block of the RAM memory when the validity of the flash image file is normal in the second step. The method of claim 1, wherein the sixth process Starting a kernel operation of the Linux to jump to a start address of the kernel of the Linux; And And a second step of starting the Linux operation of the embedded system based on the flash memory when the kernel operation of the Linux is started in the first step. The method of claim 1, A Linux operating system boot method, characterized in that the Linux kernel image is a binary file.