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authorAnuj Shah <anujshah584@gmail.com>2024-05-13 13:55:24 +0530
committerGitHub <noreply@github.com>2024-05-13 02:25:24 -0600
commit094f083fbcb36c1281b4d7fae149dff1afc0685d (patch)
tree6cf08ed17dabf95b2e46940d5cddc7ba4b81299d
parent00a1071fe45890840cdb7e989964ec2b9eefe6b2 (diff)
[linker/en] translate from Russian (#3971)
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1 files changed, 195 insertions, 1 deletions
diff --git a/linker.html.markdown b/linker.html.markdown
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--- a/linker.html.markdown
+++ b/linker.html.markdown
@@ -3,7 +3,201 @@ category: tool
tool: linker
contributors:
- ["Alexander Kovalchuk", "https://github.com/Zamuhrishka"]
+translators:
+ - ["Anuj Shah", "https://github.com/ShahAnuj2610"]
---
-This article is available in [Russian](https://learnxinyminutes.com/docs/ru-ru/linker-ru/).
+## Basic concepts and definitions
+**Position counter** - the linker has a special variable
+"." (dot) always contains the current output position.
+
+## Functions
+
+**ADDR (section)** - returns the absolute address of the specified section. However
+this section must be defined before using the ADDR function.
+
+**ALIGN (exp)** - returns the value of the position counter aligned to the border
+following the exp expression.
+
+**SIZEOF (section)** - returns the size of the section in bytes.
+
+**FILL (param)** - defines the fill pattern for the current section. All
+other unspecified regions within the section are filled with the value indicated
+in function argument.
+
+**KEEP (param)** - used to mark param as fatal.
+
+**ENTRY (func)** - defines the function that will be the entry point
+into the program.
+
+```bash
+# Determine the entry point to the program
+ENTRY(Reset_Handler)
+
+# Define a variable that contains the address of the top of the stack
+_estack = 0x20020000;
+# Define a variable that contains a heap size value
+_Min_Heap_Size = 0x200;
+# Define a variable that contains the value of the stack size
+_Min_Stack_Size = 0x400;
+
+# Description of the memory card available for this processor
+# MEMORY
+# {
+#MEMORY_DOMAIN_NAME (access rights): ORIGIN = START_ADDRESS, LENGTH = SIZE
+# }
+# In our example, the controller contains three memory areas:
+# RAM - starts with the address 0x20000000 and takes 128 KB;
+# CCMRAM - starts with the address 0x10000000 and occupies 64 KB;
+# FLASH - starts with the address 0x8000000; takes 1024 Kb;
+# Moreover, RAM memory access for reading, writing and execution.
+# CCMRAM memory is read-write only.
+# FLASH memory is available for reading and execution.
+MEMORY
+{
+ RAM (xrw) : ORIGIN = 0x20000000, LENGTH = 128K
+ CCMRAM (rw) : ORIGIN = 0x10000000, LENGTH = 64K
+ FLASH (rx) : ORIGIN = 0x8000000, LENGTH = 1024K
+}
+
+# We describe output sections
+SECTIONS
+{
+ # The first section contains a table of interrupt vectors
+ .isr_vector :
+ {
+ # Align the current position to the border of 4 bytes.
+ . = ALIGN(4);
+
+ # There is an option --gc-sections, which allows you to collect garbage from unused
+ # input sections. And if there are sections that the garbage collector should not touch,
+ # you need to specify them as an argument to the KEEP () function (analogue of the keyword
+ # volatile).
+ # The entry (* (. Isr_vector)) means the .isr_vector sections in all object files. Because
+ # appeal to the section in general terms looks like this: (FILE_NAME (SECTION_NAME))
+ KEEP(*(.isr_vector))
+
+ # Align the current position to the border of 4 bytes.
+ . = ALIGN(4);
+
+ # The expression "> MEMORY AREA" indicates which area of ​​memory will be placed
+ # this section. In our section, the .isr_vector section will be located in FLASH memory.
+ } >FLASH
+
+# TOTAL: The .isr_vector section that contains the table of interrupt vectors is aligned
+# on the border of 4 bytes, marked as inaccessible to the garbage collector and placed at the beginning
+# FLASH microcontroller memory.
+
+ # The second section contains the program code.
+ .text :
+ {
+ # Align the current position to the border of 4 bytes.
+ . = ALIGN(4);
+
+ # We indicate that in this section the .text areas of all
+ # object files
+ *(.text)
+ *(.text*)
+
+ # Protect the .init and .fini sections from the garbage collector
+ KEEP (*(.init))
+ KEEP (*(.fini))
+
+ # Align the current position to the border of 4 bytes.
+ . = ALIGN(4);
+
+ # The variable _etext is defined, which stores the address of the end of the .text section and which
+ # may be available in the source code of the program through the announcement
+ # volaile unsigned int extern _etext;
+ _etext = .;
+ } >FLASH
+
+# TOTAL: The .text section that contains the program code is aligned on the border of 4 bytes,
+# includes: all sections with program code in all object files and protected
+# from the garbage collector of the .init and .fini sections in all object files, located in FLASH
+# microcontroller memory immediately after the table of vectors.
+# The text, .init, and .fini sections. are located in memory in the order in which they
+# declared in the script.
+
+ # The third section contains constant data.
+ .rodata :
+ {
+ # Align the current position to the border of 4 bytes.
+ . = ALIGN(4);
+
+ # We indicate that in this section areas .rodata will be stored
+ # object files
+ *(.rodata)
+ *(.rodata*)
+
+ # Align the current position to the border of 4 bytes.
+ . = ALIGN(4);
+ } >FLASH
+
+ # Save the absolute address of the .data section in the _sidata variable
+ _sidata = LOADADDR(.data);
+
+ # The fourth section contains initialized variables.
+ .data :
+ {
+ # Align the current position to the border of 4 bytes.
+ . = ALIGN(4);
+
+ # Save the address of the current position (beginning of the section) in the variable _sdata
+ _sdata = .;
+
+ # We indicate that in this section the .data areas of all
+ # объектных файлов
+ *(.data)
+ *(.data*)
+
+ # Align the current position to the border of 4 bytes.
+ . = ALIGN(4);
+
+ # Save the address of the current position (end of section) in the variable _sdata
+ _edata = .;
+
+ # AT function indicates that this sector is stored in one memory area
+ # (in our case, FLASH), and it will be executed from another area of ​​memory (in our case, RAM).
+ # There are two types of addresses:
+ # * VMA (Virtual memory address) - this is the run-time address at which the compiler expects
+ # see data.
+ # * LMA (Load memory address) is the address at which the linker stores data.
+
+ #Startup must code to copy the .data section from the LMA addresses to the VMA addresses.
+
+ } >RAM AT> FLASH
+
+ # The fifth section contains zero-initialized variables.
+ .bss :
+ {
+ # Save the address of the current position (beginning of the section) in the variable _sbss and __bss_start__
+ _sbss = .;
+ __bss_start__ = _sbss;
+
+ # We indicate that in this section the .bss areas of all
+ # object files
+ *(.bss)
+ *(.bss*)
+
+ # Align the current position to the border of 4 bytes.
+ . = ALIGN(4);
+
+ # Save the address of the current position (beginning of the section) in the variable _ebss and __bss_end__
+ _ebss = .;
+ __bss_end__ = _ebss;
+ } >RAM
+
+ # The sixth section contains a bunch and a stack. It is located at the very end of RAM.
+ ._user_heap_stack :
+ {
+ . = ALIGN(4);
+ PROVIDE ( end = . );
+ PROVIDE ( _end = . );
+ . = . + _Min_Heap_Size;
+ . = . + _Min_Stack_Size;
+ . = ALIGN(4);
+ } >RAM
+}
+```