Hi,
a custiomer is trying to get the EMIF working for their custom AM4384 board.
Memory used is a Micron B2432B4MA-1DIT-F 256Mb LPDDR2-533, notable differences to the EVM is the use of a 24MHz main crystal. The board is booting fine into u-boot-spl (modified u-boot-2017.01+gitAUTOINC+53133404c8-g53133404c8, same unmodified source works on EVM), but memory access is corrupt in a strange pattern.
As the CPU crashes immediately after accessing the wrongly configured DRAM, we write a pattern `void board_init_f(ulong dummy)` in and abort the boot immediately afterwards. Validation / interpretation of the pattern is then manually done through JTAG. The values itself are OK (eg, we reliably read whatever value written), but it seems the data is shifted (either during read or write) within its burst group.
The displacement pattern looks like this:
Target addr Offset Readback addr
0x0 0x20 0x20
0x4 0x20 0x24
0x8 0x10 0x18
0xC 0x10 0x1C
0x10 0 0x10
0x14 0 0x14
0x18 -0x10 0x8
0x1C -0x10 0xC
0x20 0x20 0x40
On the Clock side we do not suspect issues, as one of the DQS lines showed a clear and stable 266MHz signal.
Can you help us out with finding our issue?
Attached are the following files (not in this thread though):
* u-boot_sumup-solo.diff: diff between u-boot-2017.01+gitAUTOINC+53133404c8-g53133404c8 and our modified version
* EMIF-regs.txt: Register dump of all EMIF regs
* memdump.txt: Memdump of pattern that is observed through JTAG
* AM43xx_DDR_register_calc_tool_sumup.xls: XLS file used to calculate modified EMIF registers
Thanks
Fred
