This is the mail archive of the
binutils@sources.redhat.com
mailing list for the binutils project.
embedded system ld script issues
- From: Bryce Schober <bryce dot schober at dynonavionics dot com>
- To: binutils at sources dot redhat dot com
- Date: Tue, 27 Apr 2004 10:30:18 -0700
- Subject: embedded system ld script issues
I'm trying to write my own ld script for use in an embedded system, but
I'm having a hard time with a couple of things. (I'm pretty much a
newbie with ld)
First, what does the memory help (malloc, etc) need from the ld script?
Second, how can I define a memory map (where sections of code / data
should go) in one place, to be used by source and in linkage? I have
been using a .h header file which #defines several constants, but it
seems that those aren't visible symbols in the ld script.
What I want to do is define a memory map of my flash part in one file
and have the address and size of each section depend on the used flash
part and be accessible both to source C code and for the linking process.
An example memory map:
#if FLASHTYPE_NEW
#define FLASH_SIZE 0x00100000
#define FLASH_SECTOR_SIZE 0x00001000
#endif
#if FLASHTYPE_OLD
#define FLASH_SIZE 0x00040000
#define FLASH_SECTOR_SIZE 0x00000800
#endif
/**************************************/
#define BOOT_ADDR 0x00000000
#define BOOT_SIZE (BOOT_END-BOOT_ADDR)
#define BOOT_END 0x00004000
/**************************************/
#define EEPROM_ADDR BOOT_END
#define EEPROM_SIZE (2*FLASH_SECTOR_SIZE)
#define EEPROM_END (EEPROM_ADDR+EEPROM_SIZE)
/**************************************/
#define CODE_ADDR EEPROM_END
#define CODE_SIZE (FLASH_SIZE-CODE_ADDR)
#define CODE_END (CODE_ADDR+CODE_SIZE)
/**************************************/
--
Bryce Schober
Design Engineer
Dynon Avionics, Inc.
www.dynonavionics.com