On i.MX, the PCIe reference clock might come from either internal system PLL or external clock source. Add the external reference clock source for reference clock. Main change in v4: - Add one more reference clock "extref" to be onhalf the reference clock that comes from external crystal oscillator. Main change in v3: - Update the logic check external reference clock mode is enabled or not in the driver codes. Main change in v2: - Fix yamllint warning. - Refine the driver codes. [PATCH v4 1/3] dt-bindings: PCI: dwc: Add one more reference clock [PATCH v4 2/3] dt-binding: pci-imx6: Add external reference clock [PATCH v4 3/3] PCI: imx6: Add external reference clock mode support Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.yaml | 7 ++++++- Documentation/devicetree/bindings/pci/snps,dw-pcie-common.yaml | 6 ++++++ drivers/pci/controller/dwc/pci-imx6.c | 20 +++++++++++++------- 3 files changed, 25 insertions(+), 8 deletions(-)
