IMX6SLL - DDR Stress Tool Calibration

[vlintilhac]

Hi,

I was using the DDR Stress Tool for calibrating my LPDDR3 (W63CH2MBV from Winbond) chip on my custom board. 

But the read calibration failed and no delay windows was found. I tried to change the DSE value in the init scrip to match the impedance (given by the PCB manufacturer) but I cannot get a valid windows for the Read calibration. Any idea for debugging?

Plus I encountered some weird output values (0xFFFF) for the calibration, see below. Any reason for this?

Best,

Vincent

ARM Clock set to 1GHz

============================================
DDR configuration
DDR type is LPDDR3 in 1-channel mode.
Data width: 32, bank num: 8
Row size: 14, col size: 10
Chip select CSD0 is used
Density per chip select: 512MB
Density per channel: 512MB
============================================

Current Temperature: 42
============================================

Please select the DDR density per CHANNEL (in bytes) on the board
Type 0 for 2GB; 1 for 1GB; 2 for 512MB; 3 for 256MB; 4 for 128MB; 5 for 64MB; 6 for 32MB
Note, if there are two chip selects per channel, then input the combined density of
both chip selects per channel

Would do you want to change VDD_SOC_CAP/VDD_ARM_CAP voltage? Type 'y' to run and 'n' to skip

Would do you want run DDR Calibration? Type 'y' to run and 'n' to skip

Calibration will run at DDR frequency 400MHz. Type 'y' to continue.
If you want to run at other DDR frequency. Type 'n'
DDR Freq: 396 MHz

Note: Array result[] holds the DRAM test result of each byte.
0: test pass. 1: test fail
4 bits respresent the result of 1 byte.
result 0001:byte 0 fail.
result 0011:byte 0, 1 fail.

Starting Read calibration...

ABS_OFFSET=0x00000000result[00]=0x1111
ABS_OFFSET=0x04040404result[01]=0x1111
ABS_OFFSET=0x08080808result[02]=0x1111
ABS_OFFSET=0x0C0C0C0Cresult[03]=0x1111
ABS_OFFSET=0x10101010result[04]=0x1111
ABS_OFFSET=0x14141414result[05]=0x1111
ABS_OFFSET=0x18181818result[06]=0x1111
ABS_OFFSET=0x1C1C1C1Cresult[07]=0xFFFF
ABS_OFFSET=0x20202020result[08]=0x1111
ABS_OFFSET=0x24242424result[09]=0x1111
ABS_OFFSET=0x28282828result[0A]=0xFFFF
ABS_OFFSET=0x2C2C2C2Cresult[0B]=0x1111
ABS_OFFSET=0x30303030result[0C]=0xBFFF
ABS_OFFSET=0x34343434result[0D]=0x1111
ABS_OFFSET=0x38383838result[0E]=0x1111
ABS_OFFSET=0x3C3C3C3Cresult[0F]=0x1111
ABS_OFFSET=0x40404040result[10]=0xFFFF
ABS_OFFSET=0x44444444result[11]=0xFFFF
ABS_OFFSET=0x48484848result[12]=0xFFFF
ABS_OFFSET=0x4C4C4C4Cresult[13]=0xFFFF
ABS_OFFSET=0x50505050result[14]=0x1111
ABS_OFFSET=0x54545454result[15]=0x1111
ABS_OFFSET=0x58585858result[16]=0x1111
ABS_OFFSET=0x5C5C5C5Cresult[17]=0x1111
ABS_OFFSET=0x60606060result[18]=0x1111
ABS_OFFSET=0x64646464result[19]=0xFFFF
ABS_OFFSET=0x68686868result[1A]=0x1111
ABS_OFFSET=0x6C6C6C6Cresult[1B]=0x1111
ABS_OFFSET=0x70707070result[1C]=0xFFFF
ABS_OFFSET=0x74747474result[1D]=0x1111
ABS_OFFSET=0x78787878result[1E]=0xFFFF
ABS_OFFSET=0x7C7C7C7Cresult[1F]=0x1111

ERROR FOUND, we can't get suitable value !!!!
dram test fails for all values.

Error: failed during ddr calibration

[Yuri]

@vlintilhac 
Hello,

  hope the following helps.

https://community.nxp.com/t5/i-MX-Processors/ddr3-calibration-error-strange-write-leveling-result/m-...

Regards,
Yuri.