topic Re: iMX8M mini DDR4 data bits swap in i.MX Processors

iMX8M mini DDR4 data bits swap

saidjazouly — Tue, 13 Oct 2020 14:24:15 GMT

Hi,

we have a custom design based on i.MX8 with a DDR4 memory.

we customized the design so that the i.MX8M DDR4 data lines are swapped and not routed directly to the DDR4 in the same order of pins, for ex:

In a previous design where we used LPDDR4 memory, we had a special tab in the excel tool MX8M_Mini_LPDDR4_RPA_v15 to make the bit swapping:

However we don't have such a tab in the DDR4 tool MX8M_Mini_DDR4_RPA_v11

How can we perform the data bit swapping in this case?
Is it possible to do a complete DDR4 configuration and perform the stress tests and get the timings using "Config Tools for i.MX v7"
Any helpful procedure that we can follow?

Thanks very much.

Re: iMX8M mini DDR4 data bits swap

weidong_sun — Wed, 14 Oct 2020 00:26:39 GMT

Hi saidjazouly ,

For iMX8MM-EVK, we have 2 versions, one is i.mx8mm + lpddr4, the other is imx8mm+DDR4. attachment is 8MMINID4-EVK-DESIGNFILES. you can refer to it to design your product.

For DDR4, there is no restriction on the exchange of data bits, as you can see in this design files.

Have a nice day!

B.R,

weidong

Re: iMX8M mini DDR4 data bits swap

saidjazouly — Wed, 14 Oct 2020 00:34:36 GMT

Thank you for the reply.

Good to know that there are no limitations on swapping the DDR4 data lines, however how do we tell the DDR4 tool MX8M_Mini_DDR4_RPA_v11 to do the DQ lanes swapping in order to start a DDR4 stress test for our custom design?

attached is the MX8M_Mini_DDR4_RPA_v11 file we use.

thank you!