Hi, We've been having a strange problem during our board bringup. I have given a brief description about our board, the problem we are facing and investigation done so far. Would appreciate any comments/pointers for further investigations.. I apologize in advance for the long post that follows..:-)
Regards Vijay
Board description: This is a MPC8360E based board with a S29GL01GP12T (16 bit) flash (size=128MB) and 256 MB DDRRam + other peripherals. We have a BDI2000 JTAG debugger connected to the board. Relevant sections of our BDI config file are given below,
[INIT] ; init core register WREG MSR 0x00001002 ;MSR : ME,RI
; Move MBAR to 0xe0000000 WM32 0xff400000 0xe0000000 ;MBAR to 0xe0000000
; Initialize LAWBAR's WM32 0xe0000020 0xf8000000 ;LBLAWBAR0 : Flash WM32 0xe0000024 0x8000001a ;LBLAWAR0 : * WM32 0xe00000A0 0x00000000 ;DDRLAWBAR0: DDR Main SODIMM WM32 0xe00000A4 0x8000001b ;DDRLAWAR0 : 256M
...
WM32 0xe0005000 0xf8001001 ;BR0 : Flash WM32 0xe0005004 0xf80069f7 ;OR0 : Flash 32M
...
[TARGET] BOOTADDR 0xfff00100 ;boot address used for start-up break RCW 0x84600000 0x04030006 ;override reset configuration words
...
[FLASH] CHIPTYPE MIRRORX16 ;Flash type: Spansion S29GL01GP CHIPSIZE 0x08000000 ;The size of one flash chip in bytes BUSWIDTH 16 ;The width of the flash memory bus in bits (8 | 16 | 32 | 64) ;WORKSPACE 0x00200000 ;workspace in DDR RAM
With this the processor halts at 0xFFF00100 on reset. We are able to read the system configuration registers at the relocated IMMR address and able to access the DDR Ram (starting at 0x00000000) and Flash starting at (0xF8000000). The flash contains some data that was pre-programmed (First sector contains HRCW and a U-boot image is also burned at another location).
Problem description: We are able to read the contents of the flash, but unable to erase or program it (we have tried several combinations of sectors). We can confirm the read because of the pre-programmed content (HRCW + U-boot image).
Is it possible to isolate this to a HW/SW(config file) issue??
Investigation done so far: We have done the following so far,
1. We have probed the address and data lines along with other control signals (Chip select etc..). Also we have made sure that the write protect remains high for the flash. All the address lines are toggling and data lines seem to be ok (since we are able to read stuff ok from the flash). Also chip select is getting issued properly at the correct time. (All these, as per our hw guys).
2. We have tried mapping the flash at different addresses with the same result
3. We used the same flash on a Freescale MDS reference board (with the same configuration for Flash) and are able to read and write successfully. Also the U-boot image burned in the flash comes up.
4. We tried using the protocol defined in the datasheet to read the 'manufacturer id' using BDI MM/MD commands. But this seems to fail in both our board and the MDS board.