Hi,
I have i.MX6qdl board where usdhc3 is designed for SD card slot. I'm using Linux from linux-2.6-imx.git - Freescale i.MX Linux Tree with imx_4.1.15_1.0.0_ga tag.
On the Linux, I have a continuous /dev/urandom test followed by pattern(attached sd_test.sh). Test seems working with single iteration after that it triggers mmc errors. So when I take the card from target and plug-in to host the card seems not mountable, but able to see the partitions.
Here are the pads, I have used:
MX6QDL_PAD_SD3_CMD__SD3_CMD 0x17061
MX6QDL_PAD_SD3_CLK__SD3_CLK 0x10059
MX6QDL_PAD_SD3_DAT0__SD3_DATA0 0x17061
MX6QDL_PAD_SD3_DAT1__SD3_DATA1 0x17061
MX6QDL_PAD_SD3_DAT2__SD3_DATA2 0x17061
MX6QDL_PAD_SD3_DAT3__SD3_DATA3 0x17061
Here are the Linux frequency details.
# cat /sys/kernel/debug/mmc0/ios
clock: 50000000 Hz
actual clock: 49500000 Hz
# cat /sys/kernel/debug/mmc0/clock
50000000
Attached kernel_sd.log for boot log and mmc issues.
Any inputs please let us know.
Thanks for the response Igor.
So, are you fine with the pad configurations and drive frequency? Do you think it is stability issue with respect to the existing i.MX kernel?
Hi Jagan
pad configurations and drive frequency can be judged based on emmc waveforms
on oscilloscope, they should be good shape and conform timings given in
sect.4.12.4 Ultra High Speed SD/SDIO/MMC Host Interface (uSDHC) AC Timing
i.MX6Q Datasheet
http://www.nxp.com/docs/en/data-sheet/IMX6DQCEC.pdf
Best regards
igor
Hi Jagan
one can try with new kernels from source.codeaurora.org/external/imx/linux-imx repository
also one can test with brand new card since issue may be caused by mmc wearing.
Best regards
igor
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