Re: [PATCH v5 4/4] PCI: qcom: Switch pcie_1_pipe_clk_src after PHY init in SC7280

Prasad Malisetty
2021-08-17T17:27:10Z

On 2021-08-10 09:38, Prasad Malisetty wrote:
> On the SC7280, By default the clock source for pcie_1_pipe is
> TCXO for gdsc enable. But after the PHY is initialized, the clock
> source must be switched to gcc_pcie_1_pipe_clk from TCXO.
>
> Signed-off-by: Prasad Malisetty <pmaliset@codeaurora.org>
> ---
> drivers/pci/controller/dwc/pcie-qcom.c | 18 ++++++++++++++++++
> 1 file changed, 18 insertions(+)
>
> diff --git a/drivers/pci/controller/dwc/pcie-qcom.c
> b/drivers/pci/controller/dwc/pcie-qcom.c
> index 8a7a300..39e3b21 100644
> --- a/drivers/pci/controller/dwc/pcie-qcom.c
> +++ b/drivers/pci/controller/dwc/pcie-qcom.c
> @@ -166,6 +166,8 @@ struct qcom_pcie_resources_2_7_0 {
> struct regulator_bulk_data supplies[2];
> struct reset_control *pci_reset;
> struct clk *pipe_clk;
> + struct clk *gcc_pcie_1_pipe_clk_src;
> + struct clk *phy_pipe_clk;
> };
>
> union qcom_pcie_resources {
> @@ -1167,6 +1169,16 @@ static int qcom_pcie_get_resources_2_7_0(struct
> qcom_pcie *pcie)
> if (ret < 0)
> return ret;
>
> + if (of_device_is_compatible(dev->of_node, "qcom,pcie-sc7280")) {
> + res->gcc_pcie_1_pipe_clk_src = devm_clk_get(dev, "pipe_mux");
> + if (IS_ERR(res->gcc_pcie_1_pipe_clk_src))
> + return PTR_ERR(res->gcc_pcie_1_pipe_clk_src);
> +
> + res->phy_pipe_clk = devm_clk_get(dev, "phy_pipe");
> + if (IS_ERR(res->phy_pipe_clk))
> + return PTR_ERR(res->phy_pipe_clk);
> + }
> +

Hi All,

Greetings!

I would like to check is there any other better approach instead of
compatible method here as well or is it fine to use compatible method.

Thanks
-Prasad

> res->pipe_clk = devm_clk_get(dev, "pipe");
> return PTR_ERR_OR_ZERO(res->pipe_clk);
> }
> @@ -1255,6 +1267,12 @@ static void qcom_pcie_deinit_2_7_0(struct
> qcom_pcie *pcie)
> static int qcom_pcie_post_init_2_7_0(struct qcom_pcie *pcie)
> {
> struct qcom_pcie_resources_2_7_0 *res = &pcie->res.v2_7_0;
> + struct dw_pcie *pci = pcie->pci;
> + struct device *dev = pci->dev;
> + struct device_node *node = dev->of_node;
> +
> + if (of_property_read_bool(node, "pipe-clk-source-switch"))
> + clk_set_parent(res->gcc_pcie_1_pipe_clk_src, res->phy_pipe_clk);
>
> return clk_prepare_enable(res->pipe_clk);
> }