For slow devices, the memory controller is usually setup to use the GPCM. Check your options and base registers (OR0 and BR0).
What is GPCM? Which source/header file I need to check for these settings.?
Hi Prakash, I didn't know that a IBM PPC440 CPU didn't contain an embedded memory controller. I assumed it did and therefore mentioned the GPCM (General Purpose Chip Select Machine - Terminology used on Freescale SoCs). Since your controller is obviously external/custom, it's hard to help you.
You mention different size.. is the port size different too?
I think u-boot takes care of port size as if we do not define the port size then u-boot search with all possible port size. BTW how I can cross-check the port size?
Hmm.. As I don't have a 440 system, it's hard to tell. But on other systems, the port-size is programmed for each chip-select, and tells the memory controller the supported bus width connected to each device for a given chip-select.
For M29W128GH I have to do some code fixup from patch suggested by Stefan. Is there any special code fixup is required for S29GL512P flash chip support?
As I mentioned before, we didn't do anything special in order to get S29GL512P working for our board.
Best regards, Frank
Thanks & Regards, Prakash
On Fri, Apr 9, 2010 at 6:57 PM, Frank Svendsbøe frank.svendsboe@gmail.com wrote:
I am using PPC440x5 Cpu core. How to check the chip-select flash is using? Earlier I have run the same code for M29W128GH and it works fine. But with S29GL512 it is not working. Now the difference is only in size and write/read timings. So I believe it should work in smooth manner.
Hmm.. If you're supposed to boot from this device, then I assume the flash is connected to CS0.For slow devices, the memory controller is usually setup to use the GPCM. Check your options and base registers (OR0 and BR0). Everything related to timing (for GPCM controlled devices) is done in these two registers.
If you have a BDI JTAG, you can set these registers using that and try to perform flash operations from here. Again, if you can, try to access the flash using the JTAG before experimenting with U-Boot.
You mention different size.. is the port size different too?
In order to help you, I think the community needs more info about your system. Stefan asked for logs, etc.
Regards, Frank