[PATCH v4 4/4] PCIe: qcom: Add support to control pipe clk src

From: Prasad Malisetty
Date: Fri Jul 16 2021 - 09:59:47 EST


This is a new requirement for sc7280 SoC.
To enable gdsc gcc_pcie_1_pipe_clk_src should be TCXO.
after PHY initialization gcc_pcie_1_pipe_clk_src needs
to switch from TCXO to gcc_pcie_1_pipe_clk.

Signed-off-by: Prasad Malisetty <pmaliset@xxxxxxxxxxxxxx>
---
drivers/pci/controller/dwc/pcie-qcom.c | 22 ++++++++++++++++++++++
1 file changed, 22 insertions(+)

diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
index 8a7a300..9e0e4ab 100644
--- a/drivers/pci/controller/dwc/pcie-qcom.c
+++ b/drivers/pci/controller/dwc/pcie-qcom.c
@@ -166,6 +166,9 @@ 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;
+ struct clk *ref_clk_src;
};

union qcom_pcie_resources {
@@ -1167,6 +1170,20 @@ 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);
+
+ res->ref_clk_src = devm_clk_get(dev, "ref");
+ if (IS_ERR(res->ref_clk_src))
+ return PTR_ERR(res->ref_clk_src);
+ }
+
res->pipe_clk = devm_clk_get(dev, "pipe");
return PTR_ERR_OR_ZERO(res->pipe_clk);
}
@@ -1255,6 +1272,11 @@ 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;
+
+ if (of_device_is_compatible(dev->of_node, "qcom,pcie-sc7280"))
+ clk_set_parent(res->gcc_pcie_1_pipe_clk_src, res->phy_pipe_clk);

return clk_prepare_enable(res->pipe_clk);
}
--
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