[PATCH 1/2] PCIe: imx6: imx7d: add support for internal phy refclk source

["André Draszik" <git@andred.net>]

The i.MX7D variant of the IP can use either an external
crystal oscillator input or an internal clock input as
a reference clock input for the PCIe PHY.

Add support for an optional property 'fsl,pcie-phy-refclk-internal'
If present then the internal clock input is used as
PCIe PHY reference clock source. The previous default
of using an external ocsillator input (if the property
doesn't exist), doesn't change.

Signed-off-by: André Draszik <git@andred.net>
Cc: Richard Zhu <hongxing.zhu@nxp.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Pengutronix Kernel Team <kernel@pengutronix.de>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: NXP Linux Team <linux-imx@nxp.com>
Cc: linux-pci@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
---
 drivers/pci/controller/dwc/pci-imx6.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
index 9b5cb5b70389..bb3700c9157c 100644
--- a/drivers/pci/controller/dwc/pci-imx6.c
+++ b/drivers/pci/controller/dwc/pci-imx6.c
@@ -63,6 +63,7 @@ struct imx6_pcie {
 	struct dw_pcie		*pci;
 	int			reset_gpio;
 	bool			gpio_active_high;
+	bool			phy_refclk_internal;
 	struct clk		*pcie_bus;
 	struct clk		*pcie_phy;
 	struct clk		*pcie_inbound_axi;
@@ -635,7 +636,10 @@ static void imx6_pcie_init_phy(struct imx6_pcie *imx6_pcie)
 		break;
 	case IMX7D:
 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
-				   IMX7D_GPR12_PCIE_PHY_REFCLK_SEL, 0);
+				   IMX7D_GPR12_PCIE_PHY_REFCLK_SEL,
+				   imx6_pcie->phy_refclk_internal
+				   ? IMX7D_GPR12_PCIE_PHY_REFCLK_SEL
+				   : 0);
 		break;
 	case IMX6SX:
 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
@@ -1171,6 +1175,9 @@ static int imx6_pcie_probe(struct platform_device *pdev)
 	if (ret)
 		imx6_pcie->link_gen = 1;
 
+	imx6_pcie->phy_refclk_internal =
+		of_property_read_bool(node, "fsl,pcie-phy-refclk-internal");
+
 	imx6_pcie->vpcie = devm_regulator_get_optional(&pdev->dev, "vpcie");
 	if (IS_ERR(imx6_pcie->vpcie)) {
 		if (PTR_ERR(imx6_pcie->vpcie) == -EPROBE_DEFER)
-- 
2.23.0.rc1