Re: [PATCH v2 6/7] PCI: qcom: Add QCS404 PCIe controller support

Lorenzo Pieralisi
2019-04-01T15:13:32Z

On Mon, Feb 18, 2019 at 10:04:06PM -0800, Bjorn Andersson wrote:
> The QCS404 platform contains a PCIe controller of version 2.4.0 and a
> Qualcomm PCIe2 PHY. The driver already supports version 2.4.0, for the
> IPQ4019, but this support touches clocks and resets related to the PHY
> as well, and there's no upstream driver for the PHY.
>
> On QCS404 we must initialize the PHY, so a separate PHY driver is
> implemented to take care of this and the controller driver is updated to
> not require the PHY related resources. This is done by relying on the
> fact that operations in both the clock and reset framework are nops when
> passed NULL, so we can isolate this change to only the get_resource
> function.
>
> For QCS404 we also need to enable the AHB (iface) clock, in order to
> access the register space of the controller, but as this is not part of
> the IPQ4019 DT binding this is only added for new users of the 2.4.0
> controller.
>
> Reviewed-by: Niklas Cassel <niklas.cassel@linaro.org>
> Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
> ---
> drivers/pci/controller/dwc/pcie-qcom.c | 64 +++++++++++++++-----------
> 1 file changed, 38 insertions(+), 26 deletions(-)
>
> diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
> index b4d8bcf6eb77..3724ab5de956 100644
> --- a/drivers/pci/controller/dwc/pcie-qcom.c
> +++ b/drivers/pci/controller/dwc/pcie-qcom.c
> @@ -113,7 +113,7 @@ struct qcom_pcie_resources_2_3_2 {
> };
>
> struct qcom_pcie_resources_2_4_0 {
> - struct clk_bulk_data clks[3];
> + struct clk_bulk_data clks[4];
> int num_clks;
> struct reset_control *axi_m_reset;
> struct reset_control *axi_s_reset;
> @@ -637,13 +637,16 @@ static int qcom_pcie_get_resources_2_4_0(struct qcom_pcie *pcie)
> struct qcom_pcie_resources_2_4_0 *res = &pcie->res.v2_4_0;
> struct dw_pcie *pci = pcie->pci;
> struct device *dev = pci->dev;
> + bool is_ipq = of_device_is_compatible(dev->of_node, "qcom,pcie-ipq4019");

Just a question: other host controller drivers resorted to .data
structures (ie struct of_device_id.data) to sort out per-SOC
parameters I was wondering if you want to do the same, maybe
not just yet but I noticed so I am asking.

Lorenzo

> int ret;
>
> res->clks[0].id = "aux";
> res->clks[1].id = "master_bus";
> res->clks[2].id = "slave_bus";
> + res->clks[3].id = "iface";
>
> - res->num_clks = 3;
> + /* qcom,pcie-ipq4019 is defined without "iface" */
> + res->num_clks = is_ipq ? 3 : 4;
>
> ret = devm_clk_bulk_get(dev, res->num_clks, res->clks);
> if (ret < 0)
> @@ -657,27 +660,33 @@ static int qcom_pcie_get_resources_2_4_0(struct qcom_pcie *pcie)
> if (IS_ERR(res->axi_s_reset))
> return PTR_ERR(res->axi_s_reset);
>
> - res->pipe_reset = devm_reset_control_get_exclusive(dev, "pipe");
> - if (IS_ERR(res->pipe_reset))
> - return PTR_ERR(res->pipe_reset);
> -
> - res->axi_m_vmid_reset = devm_reset_control_get_exclusive(dev,
> - "axi_m_vmid");
> - if (IS_ERR(res->axi_m_vmid_reset))
> - return PTR_ERR(res->axi_m_vmid_reset);
> -
> - res->axi_s_xpu_reset = devm_reset_control_get_exclusive(dev,
> - "axi_s_xpu");
> - if (IS_ERR(res->axi_s_xpu_reset))
> - return PTR_ERR(res->axi_s_xpu_reset);
> -
> - res->parf_reset = devm_reset_control_get_exclusive(dev, "parf");
> - if (IS_ERR(res->parf_reset))
> - return PTR_ERR(res->parf_reset);
> -
> - res->phy_reset = devm_reset_control_get_exclusive(dev, "phy");
> - if (IS_ERR(res->phy_reset))
> - return PTR_ERR(res->phy_reset);
> + if (is_ipq) {
> + /*
> + * These resources relates to the PHY or are secure clocks, but
> + * are controlled here for IPQ4019
> + */
> + res->pipe_reset = devm_reset_control_get_exclusive(dev, "pipe");
> + if (IS_ERR(res->pipe_reset))
> + return PTR_ERR(res->pipe_reset);
> +
> + res->axi_m_vmid_reset = devm_reset_control_get_exclusive(dev,
> + "axi_m_vmid");
> + if (IS_ERR(res->axi_m_vmid_reset))
> + return PTR_ERR(res->axi_m_vmid_reset);
> +
> + res->axi_s_xpu_reset = devm_reset_control_get_exclusive(dev,
> + "axi_s_xpu");
> + if (IS_ERR(res->axi_s_xpu_reset))
> + return PTR_ERR(res->axi_s_xpu_reset);
> +
> + res->parf_reset = devm_reset_control_get_exclusive(dev, "parf");
> + if (IS_ERR(res->parf_reset))
> + return PTR_ERR(res->parf_reset);
> +
> + res->phy_reset = devm_reset_control_get_exclusive(dev, "phy");
> + if (IS_ERR(res->phy_reset))
> + return PTR_ERR(res->phy_reset);
> + }
>
> res->axi_m_sticky_reset = devm_reset_control_get_exclusive(dev,
> "axi_m_sticky");
> @@ -697,9 +706,11 @@ static int qcom_pcie_get_resources_2_4_0(struct qcom_pcie *pcie)
> if (IS_ERR(res->ahb_reset))
> return PTR_ERR(res->ahb_reset);
>
> - res->phy_ahb_reset = devm_reset_control_get_exclusive(dev, "phy_ahb");
> - if (IS_ERR(res->phy_ahb_reset))
> - return PTR_ERR(res->phy_ahb_reset);
> + if (is_ipq) {
> + res->phy_ahb_reset = devm_reset_control_get_exclusive(dev, "phy_ahb");
> + if (IS_ERR(res->phy_ahb_reset))
> + return PTR_ERR(res->phy_ahb_reset);
> + }
>
> return 0;
> }
> @@ -1284,6 +1295,7 @@ static const struct of_device_id qcom_pcie_match[] = {
> { .compatible = "qcom,pcie-msm8996", .data = &ops_2_3_2 },
> { .compatible = "qcom,pcie-ipq8074", .data = &ops_2_3_3 },
> { .compatible = "qcom,pcie-ipq4019", .data = &ops_2_4_0 },
> + { .compatible = "qcom,pcie-qcs404", .data = &ops_2_4_0 },
> { }
> };
>
> --
> 2.18.0
>