Switching off 100 MHz Oscillator in "Suspend-to-RAM" mode on the qmmek board

[Ziegfried]

Hello, NXP's team

I'm using the qmmek board with processor imx8qm. For saving energy in the suspend mode I want to switch off PCIe 100MHz OSCILLATOR(DSC557-04444KI1-T). By default it's not powered off in the suspend mode. Pins A25 and A17 are configured as SC_P_PCIE_CTRL1_CLKREQ_B_HSIO_PCIE1_CLKREQ_B and SC_P_PCIE_CTRL0_CLKREQ_B_HSIO_PCIE0_CLKREQ_B respectively.Should I configure A25 and A 17 as GPIO? Should I change code in SCFW?

Thank you!

[Dhruvit]

Hi @Ziegfried,

I hope you are doing well.

Please find the answer below.

Q. Should I configure A25 and A17 as GPIO? Should I change code in SCFW?

=> One needs to modify the SCFW. As it is mentioned in the imx_reference_manual,

"The i.MX 8QuadMax/8QuadXPlus does not have hardware low power modes. All the low-power modes are implemented in SCFW using the software method."

Thanks & Regards,

Dhruvit Vasavada