• Sandrine Bailleux's avatar
    fvp: Move TSP from Secure DRAM to Secure SRAM · 53514b29
    Sandrine Bailleux authored
    The TSP used to execute from secure DRAM on the FVPs because there was
    not enough space in Trusted SRAM to fit it in. Thanks to recent RAM
    usage enhancements being implemented, we have made enough savings for
    the TSP to execute in SRAM.
    
    However, there is no contiguous free chunk of SRAM big enough to hold
    the TSP. Therefore, the different bootloader images need to be moved
    around to reduce memory fragmentation. This patch keeps the overall
    memory layout (i.e. keeping BL1 R/W at the bottom, BL2 at the top and
    BL3-1 in between) but moves the base addresses of all the bootloader
    images in such a way that:
     - memory fragmentation is reduced enough to fit BL3-2 in;
     - new base addresses are suitable for release builds as well as debug
       ones;
     - each image has a few extra kilobytes for future growth.
       BL3-1 and BL3-2 are the images which received the biggest slice
       of the cake since they will most probably grow the most.
    
    A few useful numbers for reference (valid at the time of this patch):
            |-----------------------|-------------------------------
            |  image size (debug)   |  extra space for the future
    --------|-----------------------|-------------------------------
    BL1 R/W |         20 KB         |            4 KB
    BL2     |         44 KB         |            4 KB
    BL3-1   |        108 KB         |           12 KB
    BL3-2   |         56 KB         |            8 KB
    --------|-----------------------|-------------------------------
    Total   |        228 KB         |           28 KB       = 256 KB
    --------|-----------------------|-------------------------------
    
    Although on FVPs the TSP now executes from Trusted SRAM by default,
    this patch keeps the option to execute it from Trusted DRAM. This is
    controlled by the build configuration 'TSP_RAM_LOCATION'.
    
    Fixes ARM-Software/tf-issues#81
    
    Change-Id: Ifb9ef2befa9a2d5ac0813f7f79834df7af992b94
    53514b29
platform.h 17.7 KB