We made some custom board with IMX6UL chip and MT41K64M16-125 SDRAM,and encountered problems while doing ddr calibration on board by ddr_stress_tester_v3.00. There are calibration log as follow:
SRC_SBMR1(0x020d8004) = 0x00000870
SRC_SBMR2(0x020d801c) = 0x02000001
ARM Clock set to 528MHz
DDR type is DDR3
Data width: 16, bank num: 8
Row size: 13, col size: 10
Chip select CSD0 is used
Density per chip select: 128MB
Current Temperature: 32
DDR Freq: 396 MHz
Start write leveling calibration...
running Write level HW calibration
MPWLHWERR register read out for factory diagnostics:
MPWLHWERR PHY0 = 0x00000087
HW WL cal status: no suitable delay value found for byte 1
Write leveling calibration completed but failed, the following results were found:
MMDC_MPWLDECTRL0 ch0 (0x021b080c) = 0x001F0000
Write DQS delay result:
Write DQS0 delay: 0/256 CK
Write DQS1 delay: 31/256 CK
Error: failed during write leveling calibration
The script I used can make calibration success on official board IMX6ULEVK.
Hope you can give me some advice about what happen to my board.