IMX7D using internal PCIE_REFCLK

Anonymous — Fri, 31 Mar 2023 00:21:05 GMT

Hi forum, we're using an i.MX7D SoM by Variscite on our own carrier board. The SoC on the module fails to boot because our board doesn't have a 100 MHz external PCIe reference clock, and the kernel hangs with the following line:

imx6q-pcie 33800000.pcie: PCIe PLL lock timeout

The datasheet suggests the SoC is able to use an internal reference clock. We've tried disabling ext_osc in the device tree:

&pcie { ext_osc = <0>; };

However it appears that this option is only effective for iMX8 and iMX6, not iMX7, as in NXP's kernel PCIe driver code.

As a workaround, since we don't need PCIe for our application for now, we commented out the call to imx7d_pcie_wait_for_phy_pll_lock and the kernel boots successfully without the external REFCLK. We would like to find a way to properly switch the SoC to using an internal reference clock.

We've attached the hanging kernel boot log. Much thanks.

Re: IMX7D using internal PCIE_REFCLK

Anonymous — Mon, 03 Apr 2023 18:45:29 GMT

Bumping for visibility because the post was marked as spam by mistake.

topic IMX7D using internal PCIE_REFCLK in i.MX Processors

IMX7D using internal PCIE_REFCLK

Re: IMX7D using internal PCIE_REFCLK