Re: [PATCH v7 4/4] PCI: qcom: Switch pcie_1_pipe_clk_src after PHY init in SC7280
From: Prasad Malisetty
Date: Wed Sep 15 2021 - 03:40:28 EST
On 2021-09-15 08:14, Bjorn Andersson wrote:
On Tue 14 Sep 11:19 PDT 2021, Prasad Malisetty wrote:
On the SC7280, the clock source for gcc_pcie_1_pipe_clk_src
must be the TCXO while gdsc is enabled. After PHY init successful
clock source should switch to pipe clock for gcc_pcie_1_pipe_clk_src.
Signed-off-by: Prasad Malisetty <pmaliset@xxxxxxxxxxxxxx>
---
drivers/pci/controller/dwc/pcie-qcom.c | 90
+++++++++++++++++++++++++++++-----
1 file changed, 79 insertions(+), 11 deletions(-)
diff --git a/drivers/pci/controller/dwc/pcie-qcom.c
b/drivers/pci/controller/dwc/pcie-qcom.c
index 8a7a300..380c962 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;
Afaict you have both 2 PCIe controllers on sc7280, so I think it seems
more reasonable to shorted this to "pipe_clk_src".
Agree. I will make it generic and update in next patch version.
+ struct clk *phy_pipe_clk;
+ struct clk *ref_clk_src;
};
union qcom_pcie_resources {
@@ -189,6 +192,11 @@ struct qcom_pcie_ops {
int (*config_sid)(struct qcom_pcie *pcie);
};
+struct qcom_pcie_cfg {
+ const struct qcom_pcie_ops *ops;
+ bool pcie_1_pipe_clk_src_switch;
Perhaps something little bit more generic, like pipe_clk_need_muxing?
Sure, I will change it and update in next patch version.
+};
+
struct qcom_pcie {
struct dw_pcie *pci;
void __iomem *parf; /* DT parf */
@@ -197,6 +205,7 @@ struct qcom_pcie {
struct phy *phy;
struct gpio_desc *reset;
const struct qcom_pcie_ops *ops;
+ bool pcie_1_pipe_clk_src_switch;
};
#define to_qcom_pcie(x) dev_get_drvdata((x)->dev)
@@ -1167,6 +1176,20 @@ static int qcom_pcie_get_resources_2_7_0(struct
qcom_pcie *pcie)
if (ret < 0)
return ret;
+ if (pcie->pcie_1_pipe_clk_src_switch) {
This looks much better, now it will easily scale to other platforms
that
have inherited this need.
Thanks Bjorn.
+ 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);
}
@@ -1185,6 +1208,10 @@ static int qcom_pcie_init_2_7_0(struct
qcom_pcie *pcie)
return ret;
}
+ /* Set TCXO as clock source for gcc_pcie_1_pipe_clk_src */
+ if (pcie->pcie_1_pipe_clk_src_switch)
+ clk_set_parent(res->gcc_pcie_1_pipe_clk_src, res->ref_clk_src);
+
ret = clk_bulk_prepare_enable(res->num_clks, res->clks);
if (ret < 0)
goto err_disable_regulators;
@@ -1256,6 +1283,10 @@ 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;
+ /* Set pipe clock as clock source for gcc_pcie_1_pipe_clk_src */
+ if (pcie->pcie_1_pipe_clk_src_switch)
+ clk_set_parent(res->gcc_pcie_1_pipe_clk_src, res->phy_pipe_clk);
+
return clk_prepare_enable(res->pipe_clk);
}
@@ -1456,6 +1487,39 @@ static const struct qcom_pcie_ops ops_1_9_0 = {
.config_sid = qcom_pcie_config_sid_sm8250,
};
+static const struct qcom_pcie_cfg apq8084_cfg = {
+ .ops = &ops_1_0_0,
+};
+
+static const struct qcom_pcie_cfg ipq8064_cfg = {
+ .ops = &ops_2_1_0,
+};
+
+static const struct qcom_pcie_cfg msm8996_cfg = {
+ .ops = &ops_2_3_2,
+};
+
+static const struct qcom_pcie_cfg ipq8074_cfg = {
+ .ops = &ops_2_3_3,
+};
+
+static const struct qcom_pcie_cfg ipq4019_cfg = {
+ .ops = &ops_2_4_0,
+};
+
+static const struct qcom_pcie_cfg sdm845_cfg = {
+ .ops = &ops_2_7_0,
+};
+
+static const struct qcom_pcie_cfg sm8250_cfg = {
+ .ops = &ops_1_9_0,
+};
+
+static const struct qcom_pcie_cfg sc7280_cfg = {
+ .ops = &ops_1_9_0,
+ .pcie_1_pipe_clk_src_switch = true,
+};
+
static const struct dw_pcie_ops dw_pcie_ops = {
.link_up = qcom_pcie_link_up,
.start_link = qcom_pcie_start_link,
@@ -1467,6 +1531,7 @@ static int qcom_pcie_probe(struct
platform_device *pdev)
struct pcie_port *pp;
struct dw_pcie *pci;
struct qcom_pcie *pcie;
+ const struct qcom_pcie_cfg *pcie_cfg = NULL;
First use of this variable is an assignment, so I don't see a need for
zero initialize it.
Regards,
Bjorn
Sure, I will incorporate the changes in next patch version.
int ret;
pcie = devm_kzalloc(dev, sizeof(*pcie), GFP_KERNEL);
@@ -1488,7 +1553,9 @@ static int qcom_pcie_probe(struct
platform_device *pdev)
pcie->pci = pci;
- pcie->ops = of_device_get_match_data(dev);
+ pcie_cfg = of_device_get_match_data(dev);
+ pcie->ops = pcie_cfg->ops;
+ pcie->pcie_1_pipe_clk_src_switch =
pcie_cfg->pcie_1_pipe_clk_src_switch;
pcie->reset = devm_gpiod_get_optional(dev, "perst", GPIOD_OUT_HIGH);
if (IS_ERR(pcie->reset)) {
@@ -1545,16 +1612,17 @@ static int qcom_pcie_probe(struct
platform_device *pdev)
}
static const struct of_device_id qcom_pcie_match[] = {
- { .compatible = "qcom,pcie-apq8084", .data = &ops_1_0_0 },
- { .compatible = "qcom,pcie-ipq8064", .data = &ops_2_1_0 },
- { .compatible = "qcom,pcie-ipq8064-v2", .data = &ops_2_1_0 },
- { .compatible = "qcom,pcie-apq8064", .data = &ops_2_1_0 },
- { .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 },
- { .compatible = "qcom,pcie-sdm845", .data = &ops_2_7_0 },
- { .compatible = "qcom,pcie-sm8250", .data = &ops_1_9_0 },
+ { .compatible = "qcom,pcie-apq8084", .data = &apq8084_cfg },
+ { .compatible = "qcom,pcie-ipq8064", .data = &ipq8064_cfg },
+ { .compatible = "qcom,pcie-ipq8064-v2", .data = &ipq8064_cfg },
+ { .compatible = "qcom,pcie-apq8064", .data = &ipq8064_cfg },
+ { .compatible = "qcom,pcie-msm8996", .data = &msm8996_cfg },
+ { .compatible = "qcom,pcie-ipq8074", .data = &ipq8074_cfg },
+ { .compatible = "qcom,pcie-ipq4019", .data = &ipq4019_cfg },
+ { .compatible = "qcom,pcie-qcs404", .data = &ipq4019_cfg },
+ { .compatible = "qcom,pcie-sdm845", .data = &sdm845_cfg },
+ { .compatible = "qcom,pcie-sm8250", .data = &sm8250_cfg },
+ { .compatible = "qcom,pcie-sc7280", .data = &sc7280_cfg },
{ }
};
--
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