GCC Linker Files
Um dos temas que discutimos no passado foi a prática de parametrizar o mapeamento da memória especialmente quanto as funções especificas do FreeRTOS.
Para efeito de referência, coloquei na pasta /assets/docs/linker os arquivos que descrevem o mapeamento de memória para cada arquitetura.
Futuramente pode-se documentar em mais detalhes tal assunto se vier a ser muito relevante tal debate.
Commando
foi usado o comando abaixo para obter cada arquivo, ajustado ao respectivo compilador:
avr-gcc -mmcu=atmega328p -Wl,--verbose > ld.lnk
Exemplo do Arquivo
Abaixo uma pequena parte do arquivo para ATMega328:
==================================================
/* Script for -n: mix text and data on same page */
/* Copyright (C) 2014-2015 Free Software Foundation, Inc.
Copying and distribution of this script, with or without modification,
are permitted in any medium without royalty provided the copyright
notice and this notice are preserved. */
OUTPUT_FORMAT("elf32-avr","elf32-avr","elf32-avr")
OUTPUT_ARCH(avr:5)
__TEXT_REGION_LENGTH__ = DEFINED(__TEXT_REGION_LENGTH__) ? __TEXT_REGION_LENGTH__ : 128K;
__DATA_REGION_LENGTH__ = DEFINED(__DATA_REGION_LENGTH__) ? __DATA_REGION_LENGTH__ : 0xffa0;
__EEPROM_REGION_LENGTH__ = DEFINED(__EEPROM_REGION_LENGTH__) ? __EEPROM_REGION_LENGTH__ : 64K;
__FUSE_REGION_LENGTH__ = DEFINED(__FUSE_REGION_LENGTH__) ? __FUSE_REGION_LENGTH__ : 1K;
__LOCK_REGION_LENGTH__ = DEFINED(__LOCK_REGION_LENGTH__) ? __LOCK_REGION_LENGTH__ : 1K;
__SIGNATURE_REGION_LENGTH__ = DEFINED(__SIGNATURE_REGION_LENGTH__) ? __SIGNATURE_REGION_LENGTH__ : 1K;
__USER_SIGNATURE_REGION_LENGTH__ = DEFINED(__USER_SIGNATURE_REGION_LENGTH__) ? __USER_SIGNATURE_REGION_LENGTH__ : 1K;
__DATA_REGION_ORIGIN__ = DEFINED(__DATA_REGION_ORIGIN__) ? __DATA_REGION_ORIGIN__ : 0x800060;
MEMORY
{
text (rx) : ORIGIN = 0, LENGTH = __TEXT_REGION_LENGTH__
data (rw!x) : ORIGIN = __DATA_REGION_ORIGIN__, LENGTH = __DATA_REGION_LENGTH__
eeprom (rw!x) : ORIGIN = 0x810000, LENGTH = __EEPROM_REGION_LENGTH__
fuse (rw!x) : ORIGIN = 0x820000, LENGTH = __FUSE_REGION_LENGTH__
lock (rw!x) : ORIGIN = 0x830000, LENGTH = __LOCK_REGION_LENGTH__
signature (rw!x) : ORIGIN = 0x840000, LENGTH = __SIGNATURE_REGION_LENGTH__
user_signatures (rw!x) : ORIGIN = 0x850000, LENGTH = __USER_SIGNATURE_REGION_LENGTH__
}
SECTIONS
{
.
.
.
. = ALIGN(2);
/* For future tablejump instruction arrays for 3 byte pc devices.
We don't relax jump/call instructions within these sections. */
*(.jumptables)
*(.jumptables*)
/* For code that needs to reside in the lower 128k progmem. */
*(.lowtext)
*(.lowtext*)
__ctors_start = . ;
*(.ctors)
__ctors_end = . ;
__dtors_start = . ;
*(.dtors)
__dtors_end = . ;
KEEP(SORT(*)(.ctors))
KEEP(SORT(*)(.dtors))
.
.
.
}
Referencias
- http://developer.gnome.org