Re: [PATCH 2/2] PCI: imx6: Add code to request/control "pcie_aux" clock for i.MX8MQ

Lucas Stach
2019-02-12T09:36:15Z

Am Montag, den 11.02.2019, 17:51 -0800 schrieb Andrey Smirnov:
> PCIe IP block has additional clock, "pcie_aux", that needs to be
> controlled by the driver. Add code to support that.
>
> Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
> Cc: Bjorn Helgaas <bhelgaas@google.com>
> Cc: Fabio Estevam <fabio.estevam@nxp.com>
> Cc: Chris Healy <cphealy@gmail.com>
> Cc: Lucas Stach <l.stach@pengutronix.de>
> Cc: Leonard Crestez <leonard.crestez@nxp.com>
> Cc: "A.s. Dong" <aisheng.dong@nxp.com>
> Cc: Richard Zhu <hongxing.zhu@nxp.com>
> Cc: linux-imx@nxp.com
> Cc: linux-arm-kernel@lists.infradead.org
> Cc: linux-kernel@vger.kernel.org
> Cc: linux-pci@vger.kernel.org
> Cc: Rob Herring <robh@kernel.org>
> Cc: devicetree@vger.kernel.org

Reviewed-by: Lucas Stach <l.stach@pengutronix.de>

> ---
>  drivers/pci/controller/dwc/pci-imx6.c | 16 ++++++++++++++++
>  1 file changed, 16 insertions(+)
>
> diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
> index 7cdf8f9ab244..1a7031782846 100644
> --- a/drivers/pci/controller/dwc/pci-imx6.c
> +++ b/drivers/pci/controller/dwc/pci-imx6.c
> @@ -65,6 +65,7 @@ struct imx6_pcie {
>   struct clk *pcie_phy;
>   struct clk *pcie_inbound_axi;
>   struct clk *pcie;
> + struct clk *pcie_aux;
>   struct regmap *iomuxc_gpr;
>   u32 controller_id;
>   struct reset_control *pciephy_reset;
> @@ -421,6 +422,12 @@ static int imx6_pcie_enable_ref_clk(struct imx6_pcie *imx6_pcie)
>   case IMX7D:
>   break;
>   case IMX8MQ:
> + ret = clk_prepare_enable(imx6_pcie->pcie_aux);
> + if (ret) {
> + dev_err(dev, "unable to enable pcie_aux clock\n");
> + break;
> + }
> +
>   offset = imx6_pcie_grp_offset(imx6_pcie);
>   /*
>    * Set the over ride low and enabled
> @@ -904,6 +911,9 @@ static void imx6_pcie_clk_disable(struct imx6_pcie *imx6_pcie)
>      IMX7D_GPR12_PCIE_PHY_REFCLK_SEL,
>      IMX7D_GPR12_PCIE_PHY_REFCLK_SEL);
>   break;
> + case IMX8MQ:
> + clk_disable_unprepare(imx6_pcie->pcie_aux);
> + break;
>   default:
>   break;
>   }
> @@ -1049,6 +1059,12 @@ static int imx6_pcie_probe(struct platform_device *pdev)
>   dev_err(dev, "Failed to get PCIE APPS reset control\n");
>   return PTR_ERR(imx6_pcie->apps_reset);
>   }
> +
> + imx6_pcie->pcie_aux = devm_clk_get(dev, "pcie_aux");
> + if (IS_ERR(imx6_pcie->pcie_aux)) {
> + dev_err(dev, "pcie_aux clock source missing or invalid\n");
> + return PTR_ERR(imx6_pcie->pcie_aux);
> + }
>   break;
>   default:
>   break;