Specifications
Embedded System Tools Guide (EDK 6.2i) www.xilinx.com 317
UG111 (v1.4) January 30, 2004 1-800-255-7778
PowerPC Processor
R
Figure 22-4 shows a sample address map for a PowerPC based EDK system. The figure 
shows that there can be various memories in the system. Here users need advanced 
address space management, which can be done with the help of linker script, described in 
the “Linker Script” section. 
Current Address Space Restrictions
Special Addresses
Every PowerPC system should have the boot section starting at 0xFFFFFFFC.
Default Linker Options
By default, the linker assumes that the program can occupy contigous address space from 
0xFFFF0000 to 0xFFFFFFFF. It also assumes a default stack size of 4K bytes, and a default 
heap size of 4K bytes.
To change the size of the allocated stack space, provide the following option to the 
compiler powerpc-eabi-gcc
-Wl,defsym -Wl,_STACK_SIZE=stack_size
where stack_size is the required stack size in bytes.
To change the size of the allocated heap space, provide the following option to the compiler 
powerpc-eabi-gcc
-Wl,defsym -Wl,_HEAP_SIZE=heap_size
where heap_size is the required heap size in bytes
Figure 22-4: A Sample Address Map for a PowerPC System
.boot
.boot should be at 0xFFFFFFFC
SAMPLE ADDRESS MAP
0xFFFF0000
0xFFFFFFFC
PLB BRAM
External Memory
PLB Peripherals
OPB Peripherals
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