Hi,
We are using i.MX8M custom board with Linux4.9.51_ga release.
We are facing mmc error after giving 'reset' command in uboot or 'reboot' command in kernel.
Please see the print below.
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iWave-G27 >
iWave-G27 > reset
resetting ...
U-Boot SPL 2017.03-imx_v2017.03_4.9.51_imx8m_ga+g2537522 (Nov 09 2018 - 11:00:20)
PMIC: PFUZE100 ID=0x10
check ddr4_pmu_train_imem code
check ddr4_pmu_train_imem code pass
check ddr4_pmu_train_dmem code
check ddr4_pmu_train_dmem code pass
Training FAILED
Training FAILED
check ddr4_pmu_train_imem code
check ddr4_pmu_train_imem code pass
check ddr4_pmu_train_dmem code
check ddr4_pmu_train_dmem code pass
Training FAILED
Normal Boot
Trying to boot from MMC1
mmc_load_image_raw_sector: mmc block read error
SPL: failed to boot from all boot devices
### ERROR ### Please RESET the board ###
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Anyone faced this issue?
Thanks in advance,
Regards,
Yashavantha
Solved! Go to Solution.
hi,
Since watchdog was not properly implemented in both hardware and software, the above issue had occurred.
Issue solved after proper watchdog implementation.
Hi Yashavantha
one can check if custom board shortly remove power from board in reboot as it is done on i.MX8M EVK with
nWDOG (pad GPIO1_IO02), U704 UM805RE p.10 SPF-29615 MX8M EVK schematic,
PMIC_ON_REQ and produced in the same manner as Reset Button SYS_nRST SW1702 switch.
Schematics (1)
Design Files for the i.MX 8M Evaluation Kit (EVK)(REV 0)
https://www.nxp.com/support/developer-resources/run-time-software/i.mx-developer-resources/evaluatio...
Best regards
igor
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Hi Igor,
Thank you for your reply.
This looks hardware watchdog power recycle implementation. Why it is necessary?
Can SW reboot/reset alone won't work in i.MX8M?
Regards,
Yashavantha
Hi Yashavantha
power recycle implementation avoids having to determine if a component critical
to rebooting the processor is in the necessary state to support a reboot.
Components that fit this category include (but may not be limited to):
eMMC memory card (if the hardware RST_B pin is not connected.
SD Card/socket (if the reset pin is not used to remove power to the SD Card)
QSPI
NOR
LPDDR2/3 memory
So you should analyze and determine what causes failure.
Best regards
igor
hi,
Since watchdog was not properly implemented in both hardware and software, the above issue had occurred.
Issue solved after proper watchdog implementation.