• Stefan Roese's avatar
    ppc4xx: Add Sequoia RAM-booting target · d873133f
    Stefan Roese authored
    
    
    This patch adds another build target for the AMCC Sequoia PPC440EPx
    eval board. This RAM-booting version is targeted for boards without
    NOR FLASH (NAND booting) which need a possibility to initially
    program their NAND FLASH. Using a JTAG debugger (e.g. BDI2000/3000)
    configured to setup the SDRAM, this debugger can load this RAM-
    booting image to the target address in SDRAM (in this case 0x1000000)
    and start it there. Then U-Boot's standard NAND commands can be
    used to program the NAND FLASH (e.g. "nand write ...").
    
    Here the commands to load and start this image from the BDI2000:
    
    440EPX>reset halt
    440EPX>load 0x1000000 /tftpboot/sequoia/u-boot.bin
    440EPX>go 0x1000000
    
    Please note that this image automatically scans for an already
    initialized SDRAM TLB (detected by EPN=0). This TLB will not be
    cleared. This TLB doesn't need to be TLB #0, this RAM-booting
    version will detect it and preserve it. So booting via BDI2000
    will work and booting with a complete different TLB init via
    U-Boot works as well.
    
    Signed-off-by: default avatarStefan Roese <sr@denx.de>
    d873133f