Commit 4d1821e7 authored by Bjorn Helgaas's avatar Bjorn Helgaas
Browse files

PCI: imx6: Factor out ref clock enable 



Factor out ref clock enable to make it cleaner to add imx6sx support.  No
functional change intended.

Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
Tested-by: default avatarChristoph Fritz <chf.fritz@googlemail.com>
parent b2d7a9cd

drivers/pci/host/pci-imx6.c

+24 −12
Original line number Diff line number Diff line
@@ -269,6 +269,23 @@ static int imx6_pcie_assert_core_reset(struct pcie_port *pp) 
	return 0;

}



static int imx6_pcie_enable_ref_clk(struct imx6_pcie *imx6_pcie)

{

	/* power up core phy and enable ref clock */

	regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,

			IMX6Q_GPR1_PCIE_TEST_PD, 0 << 18);

	/*

	 * the async reset input need ref clock to sync internally,

	 * when the ref clock comes after reset, internal synced

	 * reset time is too short, cannot meet the requirement.

	 * add one ~10us delay here.

	 */

	udelay(10);

	regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,

			IMX6Q_GPR1_PCIE_REF_CLK_EN, 1 << 16);

	return 0;

}



static int imx6_pcie_deassert_core_reset(struct pcie_port *pp)

{

	struct imx6_pcie *imx6_pcie = to_imx6_pcie(pp);
@@ -292,18 +309,11 @@ static int imx6_pcie_deassert_core_reset(struct pcie_port *pp) 
		goto err_pcie;

	}



	/* power up core phy and enable ref clock */

	regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,

			IMX6Q_GPR1_PCIE_TEST_PD, 0 << 18);

	/*

	 * the async reset input need ref clock to sync internally,

	 * when the ref clock comes after reset, internal synced

	 * reset time is too short, cannot meet the requirement.

	 * add one ~10us delay here.

	 */

	udelay(10);

	regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,

			IMX6Q_GPR1_PCIE_REF_CLK_EN, 1 << 16);

	ret = imx6_pcie_enable_ref_clk(imx6_pcie);

	if (ret) {

		dev_err(pp->dev, "unable to enable pcie ref clock\n");

		goto err_ref_clk;

	}



	/* allow the clocks to stabilize */

	usleep_range(200, 500);
@@ -316,6 +326,8 @@ static int imx6_pcie_deassert_core_reset(struct pcie_port *pp) 
	}

	return 0;



err_ref_clk:

	clk_disable_unprepare(imx6_pcie->pcie);

err_pcie:

	clk_disable_unprepare(imx6_pcie->pcie_bus);

err_pcie_bus: