CN119225831A

CN119225831A - CPU implicit initialization method

Info

Publication number: CN119225831A
Application number: CN202411470757.7A
Authority: CN
Inventors: 王雨龙
Original assignee: Tianjin Jinhang Computing Technology Research Institute
Current assignee: Tianjin Jinhang Computing Technology Research Institute
Priority date: 2024-10-21
Filing date: 2024-10-21
Publication date: 2024-12-31

Abstract

The invention discloses a CPU implicit initialization method, which comprises defining an initialization function, outputting an address of the initialization function to an independent section, simultaneously arranging the sections according to a set sequence, mapping an initialization function pointer to a corresponding section, checking mapping information, defining a function ini_start_func for searching a section starting position, defining a function ini_end_func for judging a section ending position, mapping the address of the function ini_start_func to the section ini_fn.0, mapping the address of the ini_end_func to the section ini_fn.z, performing address self-increasing operation, traversing pointer data of a section area, copying pointer data of the section area to funcptrnum, and operating the function in a function addressing mode. The invention outputs the initializing function address to the independent segment through ARMGCC compiler instruction, marks the starting address and the ending address through the null function address, traverses the function between the starting address and the ending address of the operating segment in the main function, and completes the operation work of the initializing function.

Description

CPU implicit initialization method

Technical Field

The invention belongs to the technical field of computer control, and relates to a CPU implicit initialization method.

Background

The ARM CPU software is initialized by firstly configuring a system clock, wherein a clock system in the ARM CPU is a core of the whole system and provides clock signals for other peripheral equipment and functions. Next, the clocks of the individual peripherals are configured as needed, the normal operation of the peripherals being dependent on the clock signal. GPIO (general purpose input output) is one of the most commonly used peripherals in ARM CPUs for connecting and controlling external devices. Therefore, parameters such as pin mode, output type, and the like of the GPIO need to be properly configured. Interrupts are an important mechanism for STM32 to handle external events. By configuring the interrupt priority and interrupt service routine, it is ensured that the system can quickly respond to external events. In addition to GPIOs and interrupts, other peripherals may need to be configured to meet specific application requirements. After all necessary configurations are completed, the user's application logic begins to run.

Disclosure of Invention

First, the technical problem to be solved

In the process of starting GD32, an on-board peripheral is required to be initialized in a main function, and the initialization functions of different peripheral are usually called sequentially according to the initialization functions of different peripheral, wherein the peripheral initialization functions are called in an APP file, and the initialization functions belong to a bottom layer function, so that the APP program and the bottom layer program are seriously coupled together, and if the bottom layer peripheral interface function is modified and the latter peripheral module is deleted, the application program is required to be correspondingly modified.

(II) technical scheme

In order to solve the technical problems, the invention provides a CPU implicit initialization method, which comprises the following steps:

S1, defining an initialization function by using a typedef key definition function pointer init_func, wherein the shape parameters and the return values of the function pointer are null type void.

The defined initialization functions comprise a network initialization function ini_wlan_fun and an ARINC 1553B bus initialization function, and a command line SHELL initialization function ini_shell_func.

S2, outputting the address of a function to an independent section by using ARMGCC compiler instruction __ attribute __ (section ("name")) and arranging the functions according to the set sequence.

The method comprises the steps of replacing x in a compiler with a segment name priority mode in a macro definition mode, for example, replacing x with an 'ini_fn' rank mode, wherein rank is the rank number 1, 2 and 3, and the like, for example, x parameters are represented by 'ini_fn', '1', 'ini_fn', '2', 'ini_fn', '3', the smaller the numerical value is, the compiler will place the corresponding function at the front position of a segment table.

The S3: ARMGCC compiler instruction __ attribute __ (used) instruction maps the initialization function pointer into the corresponding segment.

Setting a network initialization function ini_wlan_fun as a 1-level priority, mapping the network initialization function ini_wlan_fun into a section ini_fn.1 ', setting an ARINC 1553B bus initialization function ini_1553b_func as a 2-level priority, mapping the network initialization function ini_wlan_fun into a section ini_fn.2 ', setting a command line SHELL initialization function ini_shell_func as a 3-level priority, and mapping the command line SHELL_shell_func into a section ini_fn.3 '.

And S4, after compiling is completed, looking up in the map, and looking up mapping information in a map symbol table Image Symbol Table area.

The mapping information includes:

(1) The symbol name network initialization function ini_wlan_fun, the symbol address value of 0x200002c8, the symbol type of Data, the storage size of 4, and the network initialization function mapping on segment ini_fn.1.

(2) The symbol name ARINC 1553B bus initialization function ini_1553b_func, the symbol address value is 0x200002cc, the symbol type is Data, the storage size is 4, and the ARINC 1553B bus initialization function is mapped on the section ini_fn.2.

(3) The symbol name command line SHELL initialization function ini_shell_func, the symbol address value 0x200002d0, the symbol type Data, the memory size 4, and the command line SHELL initialization function map in segment ini_fn.3.

S5, defining a function ini_start_func by using the init_func function pointer definition defined in the step S1, wherein no operation is performed in the function to find the segment start position, and a function ini_end_func is defined to judge the segment end position, and no operation is performed in the function.

S6, mapping the address of the function ini_start_func into a segment 'ini_fn.0', the address of ini_end_func into a segment 'ini_fn.0', and the address of ini_end_func into a segment 'ini_fn.z', using ARMGCC compiler __ attribute __ (section ('name') instruction and __ attribute __ (used) instruction.

And S7, defining a function pointer variable funcptrnum in the step S1, assigning an initial value as an address of the function ini_start_func, performing address self-increasing operation, traversing pointer data of the extracted section area, copying the pointer data to funcptrnum, and operating the function in a function addressing mode.

(III) beneficial effects

According to the CPU implicit initialization method provided by the technical scheme, the initialization function address is output to the independent segment through ARMGCC compiler instructions, the starting address and the ending address are marked through the null function address, and the function between the starting address and the ending address of the operation segment is traversed in the main function, so that the operation work of the initialization function is completed.

Drawings

FIG. 1 is a flow chart of an embodiment of an implicit CPU initialization method.

Detailed Description

To make the objects, contents and advantages of the present invention more apparent, the following detailed description of the present invention will be given with reference to the accompanying drawings and examples.

Referring to fig. 1, the method for implicit initialization of a CPU according to the present embodiment includes the steps of:

The mapping information includes:

The section adds all the initializing functions into the defined input section in advance, and then sequentially takes out the initializing functions in the input section in the main function, so that the system can be initialized on the premise of not modifying the main function.

The foregoing is merely a preferred embodiment of the present invention, and it should be noted that modifications and variations could be made by those skilled in the art without departing from the technical principles of the present invention, and such modifications and variations should also be regarded as being within the scope of the invention.

Claims

1. A CPU implicit initialization method, characterized in that it comprises the following steps:

S1: Use the typedef keyword to define the function pointer init_func to define the initialization function;

S2: Use the ARMGCC compiler directive __attribute__((section("name"))) to output the address of an initialization function to a separate section and arrange them in the set order;

S3: The ARMGCC compiler instruction __attribute__((used)) directive maps the initialization function pointer to the corresponding segment;

S4: After the compilation is completed, check in .map and find the mapping information in the Image Symbol Table area;

S5: using the init_func function pointer defined in step S1, define a function ini_start_func to find the start position of the segment; and define a function ini_end_func to determine the end position of the segment;

S6: Use the ARMGCC compiler __attribute__((section("name"))) and __attribute__((used)) instructions to map the address of the function ini_start_func to the segment "ini_fn.0", the address of ini_end_func to the segment "ini_fn.0", and the address of ini_end_func to the segment "ini_fn.z".

S7: Define the function pointer variable funcptrnum in step S1, assign the initial value to the address of the function ini_start_func, perform the address self-increment operation, traverse and take out the pointer data in the section area and copy it to funcptrnum, and run this function through the function addressing mode.

2. The CPU implicit initialization method as described in claim 1 is characterized in that, in step S1, the formal parameters and return values of the function pointer are both of empty type void.

3. The CPU implicit initialization method as described in claim 2 is characterized in that, in step S1, the defined initialization functions include: a network initialization function ini_wlan_fun, an ARINC 1553B bus initialization function, and a command line SHELL initialization function ini_shell_func.

4. The CPU implicit initialization method as described in claim 3 is characterized in that, in step S2, x in the compiler is replaced with a segment name priority method in a macro definition manner, and x is replaced with an "ini_fn" rank method, where rank is a rank number 1, 2, 3 and so on, and the x parameter is represented by "ini_fn" "1", "ini_fn" "2", "ini_fn" "3" to represent the rank, and the smaller the value, the closer the corresponding function is to the front of the segment table.

5. The CPU implicit initialization method as described in claim 4 is characterized in that in step S3, the network initialization function ini_wlan_fun is set to level 1 priority and mapped to segment .ini_fn.1", the ARINC 1553B bus initialization function ini_1553b_func is set to level 2 priority and mapped to segment .ini_fn.2", and the command line SHELL initialization function ini_shell_func is set to level 3 priority and mapped to segment .ini_fn.3".

6. The CPU implicit initialization method as claimed in claim 5, characterized in that in step S3, the mapping information includes: a symbolic name network initialization function ini_wlan_fun, a symbolic name ARINC 1553B bus initialization function ini_1553b_func and a symbolic name command line SHELL initialization function ini_shell_func.

7. The CPU implicit initialization method as described in claim 6 is characterized in that in step S3, in the symbolic name network initialization function ini_wlan_fun, the symbolic address value is 0x200002c8, the symbolic type is Data, the storage size size is 4, and the network initialization function is mapped in segment .ini_fn.1.

8. The CPU implicit initialization method as described in claim 7 is characterized in that, in step S3, in the symbol name ARINC1553B bus initialization function ini_1553b_func, the symbol address value is 0x200002cc, the symbol type is Data, the storage size size is 4, and the ARINC 1553B bus initialization function is mapped in segment .ini_fn.2.

9. The CPU implicit initialization method as described in claim 8 is characterized in that in step S3, in the symbolic name command line SHELL initialization function ini_shell_func, the symbolic address value is 0x200002d0, the symbolic type is Data, the storage size size is 4, and the command line SHELL initialization function is mapped in segment .ini_fn.3.

10. The CPU implicit initialization method as described in claim 9 is characterized in that in step S7, section adds all initialization functions to the defined input section in advance, and then takes out the initialization functions in this input section in turn in the main function, completing the initialization of the system without modifying the main function.