I'm having some problems porting U-Boot to a custom board based closely on the original Freescale Lite5200 IceCube (not the newer Lite5200B). Specifically, I am having problems getting U-Boot to recognize our flash memory.
Our board differs from the original design in a few key ways: - uses MPC5200B processor instead of MPC5200 - the original Freescale design used the Non-MUX 24 address bit / 8 data bits from the LocalPlus bus, but we operate MUXed with 25 bit address bits and 16 data bits. - uses Am29LV641D flash memory instead of Am29LV652D
I am using u-boot-1.1.4, but modified TEXT_BASE to run out of RAM at 0x200000 (which seems to be working fine on our board).
I'm a newbie at u-boot porting, so I may have done something stupid. Because our design is closer to the original IceCube design than the newer Lite5200B design, I cloned the board/icecube folder as the starting point of my new board. I couldn't get u-boot to reach a command prompt until I read the Freescale appnote "AN3220 U-Boot Porting Guide", and changed the IPB bus speed to 133MHz as recommended for the MPC5200B processor. Other than that, I built u-boot identically to a Lite5200 board.
At the U-boot prompt, the flinfo command tells me that flash is unrecognized. I inspected MBAR+0x300, and it had a value of 0x00047800, which I interpreted to be correct for an 8-bit bus, not a 16-bit bus. After searching the u-boot code for how that gets set, I added this line to my include/configs/<board>.h file: #define CFG_CS0_CFG 0x0004F900 hoping to get flash properly reconfigured for a 16-bit MUXed bus. After rebuild, inspection of MBAR+0300 showed the new value, but u-boot still didn't recognize the flash.
Any help, please?
I have a BDI2000, if that would help me find/fix the problem.
Thanks,
Ed Jubenville