Linker Script - Placing a section at the end of a memory region

Question

I have searched far and wide for how to do this and have failed to come up with an answer.

My memory layout is as follows:

Fake Address | Section
            


        

Answer 1

I managed to solve it by calculating the size of the code by using the linker command: size. In my Makefile i set SIZE to the size of the code. I then call cpp (the preprocessor) to calculate all absolute addresses (using c-syntax). I then link using the generated linkfile: tmp.ld

%.elf: %.o
    $(eval SIZE := $(shell arm-none-eabi-size -B $<  | tail -n 1 | awk -F ' ' '{print $$1}'))
    $(CC) -DSEG_SIZE=$(SIZE) -P -E -x c link.ld -o tmp.ld
    $(CC) -o $@ $< $(LDFLAGS)

In the link.ld-file i can do all kinds of calculations (as SEG_SIZE is a constant):

#define SEG_LAST_ADDR 1234
#define MY_SEG        (SEG_LAST_ADDR - SEG_SIZE)

MEMORY
{
  bootloader     (rx)  : ORIGIN = MY_SEG,     LENGTH = SEG_SIZE
  ...
}

I finally link against the tmp.ld-file.