[PATCH v8 05/11] PCI: imx6: Introduce SoC specific callbacks for controlling REFCLK

Frank Li
2024-07-29T20:19:15Z

Instead of using the switch case statement to enable/disable the reference
clock handled by this driver itself, let's introduce a new callback
enable_ref_clk() and define it for platforms that require it. This
simplifies the code.

Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
drivers/pci/controller/dwc/pci-imx6.c | 111 ++++++++++++++++------------------
1 file changed, 51 insertions(+), 60 deletions(-)

diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
index 443c7c75f2842..b68a817ccc86b 100644
--- a/drivers/pci/controller/dwc/pci-imx6.c
+++ b/drivers/pci/controller/dwc/pci-imx6.c
@@ -102,6 +102,7 @@ struct imx_pcie_drvdata {
const u32 mode_mask[IMX_PCIE_MAX_INSTANCES];
const struct pci_epc_features *epc_features;
int (*init_phy)(struct imx_pcie *pcie);
+ int (*enable_ref_clk)(struct imx_pcie *pcie, bool enable);
};

struct imx_pcie {
@@ -583,21 +584,20 @@ static int imx_pcie_attach_pd(struct device *dev)
return 0;
}

-static int imx_pcie_enable_ref_clk(struct imx_pcie *imx_pcie)
+static int imx6sx_pcie_enable_ref_clk(struct imx_pcie *imx_pcie, bool enable)
{
- unsigned int offset;
- int ret = 0;
+ if (enable)
+ regmap_clear_bits(imx_pcie->iomuxc_gpr, IOMUXC_GPR12,
+ IMX6SX_GPR12_PCIE_TEST_POWERDOWN);

- switch (imx_pcie->drvdata->variant) {
- case IMX6SX:
- regmap_update_bits(imx_pcie->iomuxc_gpr, IOMUXC_GPR12,
- IMX6SX_GPR12_PCIE_TEST_POWERDOWN, 0);
- break;
- case IMX6QP:
- case IMX6Q:
+ return 0;
+}
+
+static int imx6q_pcie_enable_ref_clk(struct imx_pcie *imx_pcie, bool enable)
+{
+ if (enable) {
/* power up core phy and enable ref clock */
- regmap_update_bits(imx_pcie->iomuxc_gpr, IOMUXC_GPR1,
- IMX6Q_GPR1_PCIE_TEST_PD, 0 << 18);
+ regmap_clear_bits(imx_pcie->iomuxc_gpr, IOMUXC_GPR1, IMX6Q_GPR1_PCIE_TEST_PD);
/*
* the async reset input need ref clock to sync internally,
* when the ref clock comes after reset, internal synced
@@ -605,55 +605,33 @@ static int imx_pcie_enable_ref_clk(struct imx_pcie *imx_pcie)
* add one ~10us delay here.
*/
usleep_range(10, 100);
- regmap_update_bits(imx_pcie->iomuxc_gpr, IOMUXC_GPR1,
- IMX6Q_GPR1_PCIE_REF_CLK_EN, 1 << 16);
- break;
- case IMX7D:
- case IMX95:
- case IMX95_EP:
- break;
- case IMX8MM:
- case IMX8MM_EP:
- case IMX8MQ:
- case IMX8MQ_EP:
- case IMX8MP:
- case IMX8MP_EP:
- offset = imx_pcie_grp_offset(imx_pcie);
- /*
- * Set the over ride low and enabled
- * make sure that REF_CLK is turned on.
- */
- regmap_update_bits(imx_pcie->iomuxc_gpr, offset,
- IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE,
- 0);
- regmap_update_bits(imx_pcie->iomuxc_gpr, offset,
- IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE_EN,
- IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE_EN);
- break;
+ regmap_set_bits(imx_pcie->iomuxc_gpr, IOMUXC_GPR1, IMX6Q_GPR1_PCIE_REF_CLK_EN);
+ } else {
+ regmap_clear_bits(imx_pcie->iomuxc_gpr, IOMUXC_GPR1, IMX6Q_GPR1_PCIE_REF_CLK_EN);
+ regmap_set_bits(imx_pcie->iomuxc_gpr, IOMUXC_GPR1, IMX6Q_GPR1_PCIE_TEST_PD);
}

- return ret;
+ return 0;
}

-static void imx_pcie_disable_ref_clk(struct imx_pcie *imx_pcie)
+static int imx8mm_pcie_enable_ref_clk(struct imx_pcie *imx_pcie, bool enable)
{
- switch (imx_pcie->drvdata->variant) {
- case IMX6QP:
- case IMX6Q:
- regmap_update_bits(imx_pcie->iomuxc_gpr, IOMUXC_GPR1,
- IMX6Q_GPR1_PCIE_REF_CLK_EN, 0);
- regmap_update_bits(imx_pcie->iomuxc_gpr, IOMUXC_GPR1,
- IMX6Q_GPR1_PCIE_TEST_PD,
- IMX6Q_GPR1_PCIE_TEST_PD);
- break;
- case IMX7D:
- regmap_update_bits(imx_pcie->iomuxc_gpr, IOMUXC_GPR12,
- IMX7D_GPR12_PCIE_PHY_REFCLK_SEL,
- IMX7D_GPR12_PCIE_PHY_REFCLK_SEL);
- break;
- default:
- break;
+ int offset = imx_pcie_grp_offset(imx_pcie);
+
+ if (enable) {
+ regmap_clear_bits(imx_pcie->iomuxc_gpr, offset, IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE);
+ regmap_set_bits(imx_pcie->iomuxc_gpr, offset, IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE_EN);
}
+
+ return 0;
+}
+
+static int imx7d_pcie_enable_ref_clk(struct imx_pcie *imx_pcie, bool enable)
+{
+ if (!enable)
+ regmap_set_bits(imx_pcie->iomuxc_gpr, IOMUXC_GPR12,
+ IMX7D_GPR12_PCIE_PHY_REFCLK_SEL);
+ return 0;
}

static int imx_pcie_clk_enable(struct imx_pcie *imx_pcie)
@@ -666,10 +644,12 @@ static int imx_pcie_clk_enable(struct imx_pcie *imx_pcie)
if (ret)
return ret;

- ret = imx_pcie_enable_ref_clk(imx_pcie);
- if (ret) {
- dev_err(dev, "unable to enable pcie ref clock\n");
- goto err_ref_clk;
+ if (imx_pcie->drvdata->enable_ref_clk) {
+ ret = imx_pcie->drvdata->enable_ref_clk(imx_pcie, true);
+ if (ret) {
+ dev_err(dev, "Failed to enable PCIe REFCLK\n");
+ goto err_ref_clk;
+ }
}

/* allow the clocks to stabilize */
@@ -684,7 +664,8 @@ static int imx_pcie_clk_enable(struct imx_pcie *imx_pcie)

static void imx_pcie_clk_disable(struct imx_pcie *imx_pcie)
{
- imx_pcie_disable_ref_clk(imx_pcie);
+ if (imx_pcie->drvdata->enable_ref_clk)
+ imx_pcie->drvdata->enable_ref_clk(imx_pcie, false);
clk_bulk_disable_unprepare(imx_pcie->drvdata->clks_cnt, imx_pcie->clks);
}

@@ -1460,6 +1441,7 @@ static const struct imx_pcie_drvdata drvdata[] = {
.mode_off[0] = IOMUXC_GPR12,
.mode_mask[0] = IMX6Q_GPR12_DEVICE_TYPE,
.init_phy = imx_pcie_init_phy,
+ .enable_ref_clk = imx6q_pcie_enable_ref_clk,
},
[IMX6SX] = {
.variant = IMX6SX,
@@ -1474,6 +1456,7 @@ static const struct imx_pcie_drvdata drvdata[] = {
.mode_off[0] = IOMUXC_GPR12,
.mode_mask[0] = IMX6Q_GPR12_DEVICE_TYPE,
.init_phy = imx6sx_pcie_init_phy,
+ .enable_ref_clk = imx6sx_pcie_enable_ref_clk,
},
[IMX6QP] = {
.variant = IMX6QP,
@@ -1489,6 +1472,7 @@ static const struct imx_pcie_drvdata drvdata[] = {
.mode_off[0] = IOMUXC_GPR12,
.mode_mask[0] = IMX6Q_GPR12_DEVICE_TYPE,
.init_phy = imx_pcie_init_phy,
+ .enable_ref_clk = imx6q_pcie_enable_ref_clk,
},
[IMX7D] = {
.variant = IMX7D,
@@ -1501,6 +1485,7 @@ static const struct imx_pcie_drvdata drvdata[] = {
.mode_off[0] = IOMUXC_GPR12,
.mode_mask[0] = IMX6Q_GPR12_DEVICE_TYPE,
.init_phy = imx7d_pcie_init_phy,
+ .enable_ref_clk = imx7d_pcie_enable_ref_clk,
},
[IMX8MQ] = {
.variant = IMX8MQ,
@@ -1514,6 +1499,7 @@ static const struct imx_pcie_drvdata drvdata[] = {
.mode_off[1] = IOMUXC_GPR12,
.mode_mask[1] = IMX8MQ_GPR12_PCIE2_CTRL_DEVICE_TYPE,
.init_phy = imx8mq_pcie_init_phy,
+ .enable_ref_clk = imx8mm_pcie_enable_ref_clk,
},
[IMX8MM] = {
.variant = IMX8MM,
@@ -1525,6 +1511,7 @@ static const struct imx_pcie_drvdata drvdata[] = {
.clks_cnt = ARRAY_SIZE(imx8mm_clks),
.mode_off[0] = IOMUXC_GPR12,
.mode_mask[0] = IMX6Q_GPR12_DEVICE_TYPE,
+ .enable_ref_clk = imx8mm_pcie_enable_ref_clk,
},
[IMX8MP] = {
.variant = IMX8MP,
@@ -1536,6 +1523,7 @@ static const struct imx_pcie_drvdata drvdata[] = {
.clks_cnt = ARRAY_SIZE(imx8mm_clks),
.mode_off[0] = IOMUXC_GPR12,
.mode_mask[0] = IMX6Q_GPR12_DEVICE_TYPE,
+ .enable_ref_clk = imx8mm_pcie_enable_ref_clk,
},
[IMX95] = {
.variant = IMX95,
@@ -1562,6 +1550,7 @@ static const struct imx_pcie_drvdata drvdata[] = {
.mode_mask[1] = IMX8MQ_GPR12_PCIE2_CTRL_DEVICE_TYPE,
.epc_features = &imx8m_pcie_epc_features,
.init_phy = imx8mq_pcie_init_phy,
+ .enable_ref_clk = imx8mm_pcie_enable_ref_clk,
},
[IMX8MM_EP] = {
.variant = IMX8MM_EP,
@@ -1574,6 +1563,7 @@ static const struct imx_pcie_drvdata drvdata[] = {
.mode_off[0] = IOMUXC_GPR12,
.mode_mask[0] = IMX6Q_GPR12_DEVICE_TYPE,
.epc_features = &imx8m_pcie_epc_features,
+ .enable_ref_clk = imx8mm_pcie_enable_ref_clk,
},
[IMX8MP_EP] = {
.variant = IMX8MP_EP,
@@ -1586,6 +1576,7 @@ static const struct imx_pcie_drvdata drvdata[] = {
.mode_off[0] = IOMUXC_GPR12,
.mode_mask[0] = IMX6Q_GPR12_DEVICE_TYPE,
.epc_features = &imx8m_pcie_epc_features,
+ .enable_ref_clk = imx8mm_pcie_enable_ref_clk,
},
[IMX95_EP] = {
.variant = IMX95_EP,

--
2.34.1