refactor(fvp): reduce max size of HW_CONFIG to 16KB

HW_CONFIG is the hardware description consumed primarly by the Linux
kernel, and for the FVP platform, TF-A runtime firmware (BL31). Due to
both needing it, two copies of this file are made in Trusted DRAM and
SRAM. The copy in Trusted DRAM is a workaround stemming from memory
constraints in SRAM. We temporarily map the range of memory in Trusted
DRAM into BL31 to allow it to consume the configuration.  In principle,
however, BL31 execution should be limited to SRAM, hence reduce the
maximum size of the HW_CONFIG to 16KB in order to accommodate it in
SRAM. This is possible since in practice, the HW_CONFIG on FVP is only
about 11KB.

Change-Id: Idb5dc0637b402562b7177a2b4e2464c4f3f67da7
Signed-off-by: Harrison Mutai <harrison.mutai@arm.com>
1 file changed