You can find the GCC build tools manuals in the S32 design studio installation folder
GCC v6.3
<S32DS_ARM_v2018.R1>\Cross_Tools\gcc-6.3-arm32-eabi\arm-none-eabi\share\docs\pdf
GCC v4.9
<S32DS_ARM_v2018.R1>\Cross_Tools\gcc-arm-none-eabi-4_9\share\doc\gcc-arm-none-eabi\pdf
there is linker manual: ld.pdf
Section: Linker Scripts
Hope it helps.
Stan