IMX7 lower frequency support

[gopinathsriniva]

Hi All,

I am looking for lower frequency support in the range of 396MHz. Here  a link that explains how to achieve  this.  

How can i change the core frequency on iMX7S module? - Toradex Community 

I followed  the same steps in IMX7 sabreSD board. But I am unable to run IMX7 processor in 396MHz, even I have disabled display and Ethernet as per that link. Instead processor is running in 648MHz. 

Any suggestion would be greatly appreciated.

Thanks,

Gopinath S 

[igorpadykov]

Hi Gopinath

nxp official bsp have not 396MHz operating point in : linux/arch/arm/boot/dts/imx7d.dtsi

imx7d.dtsi\dts\boot\arm\arch - linux-imx - i.MX Linux kernel 

also it is not listed in Table 9. Operating ranges i.MX7D Datasheet

http://cache.nxp.com/files/32bit/doc/data_sheet/IMX7DCEC.pdf

Best regards
igor
-----------------------------------------------------------------------------------------------------------------------
Note: If this post answers your question, please click the Correct Answer button. Thank you!
-----------------------------------------------------------------------------------------------------------------------

[gopinathsriniva]

Hi Igor,

Thank You for you reply. In the Table 9, there is one mode, which says "Operation at 800 MHz and below". Can you tell me what are all the supported frequencies below 800MH >  From the TRM, in the section "Table 6-66. USB low-power boot frequencies" I can see 396MHz is possible. 

Best Regards,

Gopi

[igorpadykov]

Hi Gopinath

Table 9 shows all supported frequencies.

Best regards
igor

[alexandre_caron]

Table 9 only show voltage for different frequency. There is not info about wich frequency is supported. I have the same problem. I cannot go lower than 648 Mhz