[PATCH v4 01/15] PCI: imx6: Simplify clock handling by using bulk_clk_*() function

From: Frank Li
Date: Sun Dec 17 2023 - 00:13:07 EST


Refactors the clock handling logic in the imx6 PCI driver by adding
clk_names[] define in drvdata . Simplifies the code and makes it more
maintainable, as future additions of SOC support will only require
straightforward changes.

Signed-off-by: Frank Li <Frank.Li@xxxxxxx>
---

Notes:
Change from v3 to v4
- using clk_bulk_*() API
Change from v1 to v3
- none

drivers/pci/controller/dwc/pci-imx6.c | 128 ++++++++------------------
1 file changed, 38 insertions(+), 90 deletions(-)

diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
index 74703362aeec7..2086214345e9a 100644
--- a/drivers/pci/controller/dwc/pci-imx6.c
+++ b/drivers/pci/controller/dwc/pci-imx6.c
@@ -61,12 +61,15 @@ enum imx6_pcie_variants {
#define IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE BIT(1)
#define IMX6_PCIE_FLAG_SUPPORTS_SUSPEND BIT(2)

+#define IMX6_PCIE_MAX_CLKS 6
+
struct imx6_pcie_drvdata {
enum imx6_pcie_variants variant;
enum dw_pcie_device_mode mode;
u32 flags;
int dbi_length;
const char *gpr;
+ const char *clk_names[IMX6_PCIE_MAX_CLKS];
};

struct imx6_pcie {
@@ -74,11 +77,8 @@ struct imx6_pcie {
int reset_gpio;
bool gpio_active_high;
bool link_is_up;
- struct clk *pcie_bus;
- struct clk *pcie_phy;
- struct clk *pcie_inbound_axi;
- struct clk *pcie;
- struct clk *pcie_aux;
+ struct clk_bulk_data clks[IMX6_PCIE_MAX_CLKS];
+ u32 clks_cnt;
struct regmap *iomuxc_gpr;
u16 msi_ctrl;
u32 controller_id;
@@ -407,13 +407,18 @@ static void imx7d_pcie_wait_for_phy_pll_lock(struct imx6_pcie *imx6_pcie)

static int imx6_setup_phy_mpll(struct imx6_pcie *imx6_pcie)
{
- unsigned long phy_rate = clk_get_rate(imx6_pcie->pcie_phy);
+ unsigned long phy_rate = 0;
int mult, div;
u16 val;
+ int i;

if (!(imx6_pcie->drvdata->flags & IMX6_PCIE_FLAG_IMX6_PHY))
return 0;

+ for (i = 0; i < imx6_pcie->clks_cnt; i++)
+ if (strncmp(imx6_pcie->clks[i].id, "pcie_phy", 8) == 0)
+ phy_rate = clk_get_rate(imx6_pcie->clks[i].clk);
+
switch (phy_rate) {
case 125000000:
/*
@@ -550,19 +555,11 @@ static int imx6_pcie_attach_pd(struct device *dev)

static int imx6_pcie_enable_ref_clk(struct imx6_pcie *imx6_pcie)
{
- struct dw_pcie *pci = imx6_pcie->pci;
- struct device *dev = pci->dev;
unsigned int offset;
int ret = 0;

switch (imx6_pcie->drvdata->variant) {
case IMX6SX:
- ret = clk_prepare_enable(imx6_pcie->pcie_inbound_axi);
- if (ret) {
- dev_err(dev, "unable to enable pcie_axi clock\n");
- break;
- }
-
regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
IMX6SX_GPR12_PCIE_TEST_POWERDOWN, 0);
break;
@@ -589,12 +586,6 @@ static int imx6_pcie_enable_ref_clk(struct imx6_pcie *imx6_pcie)
case IMX8MQ_EP:
case IMX8MP:
case IMX8MP_EP:
- ret = clk_prepare_enable(imx6_pcie->pcie_aux);
- if (ret) {
- dev_err(dev, "unable to enable pcie_aux clock\n");
- break;
- }
-
offset = imx6_pcie_grp_offset(imx6_pcie);
/*
* Set the over ride low and enabled
@@ -615,9 +606,6 @@ static int imx6_pcie_enable_ref_clk(struct imx6_pcie *imx6_pcie)
static void imx6_pcie_disable_ref_clk(struct imx6_pcie *imx6_pcie)
{
switch (imx6_pcie->drvdata->variant) {
- case IMX6SX:
- clk_disable_unprepare(imx6_pcie->pcie_inbound_axi);
- break;
case IMX6QP:
case IMX6Q:
regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
@@ -631,14 +619,6 @@ static void imx6_pcie_disable_ref_clk(struct imx6_pcie *imx6_pcie)
IMX7D_GPR12_PCIE_PHY_REFCLK_SEL,
IMX7D_GPR12_PCIE_PHY_REFCLK_SEL);
break;
- case IMX8MM:
- case IMX8MM_EP:
- case IMX8MQ:
- case IMX8MQ_EP:
- case IMX8MP:
- case IMX8MP_EP:
- clk_disable_unprepare(imx6_pcie->pcie_aux);
- break;
default:
break;
}
@@ -650,23 +630,9 @@ static int imx6_pcie_clk_enable(struct imx6_pcie *imx6_pcie)
struct device *dev = pci->dev;
int ret;

- ret = clk_prepare_enable(imx6_pcie->pcie_phy);
- if (ret) {
- dev_err(dev, "unable to enable pcie_phy clock\n");
+ ret = clk_bulk_prepare_enable(imx6_pcie->clks_cnt, imx6_pcie->clks);
+ if (ret)
return ret;
- }
-
- ret = clk_prepare_enable(imx6_pcie->pcie_bus);
- if (ret) {
- dev_err(dev, "unable to enable pcie_bus clock\n");
- goto err_pcie_bus;
- }
-
- ret = clk_prepare_enable(imx6_pcie->pcie);
- if (ret) {
- dev_err(dev, "unable to enable pcie clock\n");
- goto err_pcie;
- }

ret = imx6_pcie_enable_ref_clk(imx6_pcie);
if (ret) {
@@ -679,11 +645,7 @@ static int imx6_pcie_clk_enable(struct imx6_pcie *imx6_pcie)
return 0;

err_ref_clk:
- clk_disable_unprepare(imx6_pcie->pcie);
-err_pcie:
- clk_disable_unprepare(imx6_pcie->pcie_bus);
-err_pcie_bus:
- clk_disable_unprepare(imx6_pcie->pcie_phy);
+ clk_bulk_disable_unprepare(imx6_pcie->clks_cnt, imx6_pcie->clks);

return ret;
}
@@ -691,9 +653,7 @@ static int imx6_pcie_clk_enable(struct imx6_pcie *imx6_pcie)
static void imx6_pcie_clk_disable(struct imx6_pcie *imx6_pcie)
{
imx6_pcie_disable_ref_clk(imx6_pcie);
- clk_disable_unprepare(imx6_pcie->pcie);
- clk_disable_unprepare(imx6_pcie->pcie_bus);
- clk_disable_unprepare(imx6_pcie->pcie_phy);
+ clk_bulk_disable_unprepare(imx6_pcie->clks_cnt, imx6_pcie->clks);
}

static void imx6_pcie_assert_core_reset(struct imx6_pcie *imx6_pcie)
@@ -1305,32 +1265,19 @@ static int imx6_pcie_probe(struct platform_device *pdev)
return imx6_pcie->reset_gpio;
}

- /* Fetch clocks */
- imx6_pcie->pcie_bus = devm_clk_get(dev, "pcie_bus");
- if (IS_ERR(imx6_pcie->pcie_bus))
- return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie_bus),
- "pcie_bus clock source missing or invalid\n");
+ while (imx6_pcie->drvdata->clk_names[imx6_pcie->clks_cnt]) {
+ int i = imx6_pcie->clks_cnt;

- imx6_pcie->pcie = devm_clk_get(dev, "pcie");
- if (IS_ERR(imx6_pcie->pcie))
- return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie),
- "pcie clock source missing or invalid\n");
+ imx6_pcie->clks[i].id = imx6_pcie->drvdata->clk_names[i];
+ imx6_pcie->clks_cnt++;
+ }
+
+ /* Fetch clocks */
+ ret = devm_clk_bulk_get(dev, imx6_pcie->clks_cnt, imx6_pcie->clks);
+ if (ret)
+ return ret;

switch (imx6_pcie->drvdata->variant) {
- case IMX6SX:
- imx6_pcie->pcie_inbound_axi = devm_clk_get(dev,
- "pcie_inbound_axi");
- if (IS_ERR(imx6_pcie->pcie_inbound_axi))
- return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie_inbound_axi),
- "pcie_inbound_axi clock missing or invalid\n");
- break;
- case IMX8MQ:
- case IMX8MQ_EP:
- imx6_pcie->pcie_aux = devm_clk_get(dev, "pcie_aux");
- if (IS_ERR(imx6_pcie->pcie_aux))
- return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie_aux),
- "pcie_aux clock source missing or invalid\n");
- fallthrough;
case IMX7D:
if (dbi_base->start == IMX8MQ_PCIE2_BASE_ADDR)
imx6_pcie->controller_id = 1;
@@ -1353,10 +1300,6 @@ static int imx6_pcie_probe(struct platform_device *pdev)
case IMX8MM_EP:
case IMX8MP:
case IMX8MP_EP:
- imx6_pcie->pcie_aux = devm_clk_get(dev, "pcie_aux");
- if (IS_ERR(imx6_pcie->pcie_aux))
- return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie_aux),
- "pcie_aux clock source missing or invalid\n");
imx6_pcie->apps_reset = devm_reset_control_get_exclusive(dev,
"apps");
if (IS_ERR(imx6_pcie->apps_reset))
@@ -1372,14 +1315,6 @@ static int imx6_pcie_probe(struct platform_device *pdev)
default:
break;
}
- /* Don't fetch the pcie_phy clock, if it has abstract PHY driver */
- if (imx6_pcie->phy == NULL) {
- imx6_pcie->pcie_phy = devm_clk_get(dev, "pcie_phy");
- if (IS_ERR(imx6_pcie->pcie_phy))
- return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie_phy),
- "pcie_phy clock source missing or invalid\n");
- }
-

/* Grab turnoff reset */
imx6_pcie->turnoff_reset = devm_reset_control_get_optional_exclusive(dev, "turnoff");
@@ -1470,6 +1405,9 @@ static void imx6_pcie_shutdown(struct platform_device *pdev)
imx6_pcie_assert_core_reset(imx6_pcie);
}

+#define IMX6_CLKS_COMMON "pcie_bus", "pcie"
+#define IMX6_CLKS_NO_PHYDRV IMX6_CLKS_COMMON, "pcie_phy"
+
static const struct imx6_pcie_drvdata drvdata[] = {
[IMX6Q] = {
.variant = IMX6Q,
@@ -1477,6 +1415,7 @@ static const struct imx6_pcie_drvdata drvdata[] = {
IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE,
.dbi_length = 0x200,
.gpr = "fsl,imx6q-iomuxc-gpr",
+ .clk_names = {IMX6_CLKS_NO_PHYDRV},
},
[IMX6SX] = {
.variant = IMX6SX,
@@ -1484,6 +1423,7 @@ static const struct imx6_pcie_drvdata drvdata[] = {
IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE |
IMX6_PCIE_FLAG_SUPPORTS_SUSPEND,
.gpr = "fsl,imx6q-iomuxc-gpr",
+ .clk_names = {IMX6_CLKS_NO_PHYDRV, "pcie_inbound_axi"},
},
[IMX6QP] = {
.variant = IMX6QP,
@@ -1492,40 +1432,48 @@ static const struct imx6_pcie_drvdata drvdata[] = {
IMX6_PCIE_FLAG_SUPPORTS_SUSPEND,
.dbi_length = 0x200,
.gpr = "fsl,imx6q-iomuxc-gpr",
+ .clk_names = {IMX6_CLKS_NO_PHYDRV},
},
[IMX7D] = {
.variant = IMX7D,
.flags = IMX6_PCIE_FLAG_SUPPORTS_SUSPEND,
.gpr = "fsl,imx7d-iomuxc-gpr",
+ .clk_names = {IMX6_CLKS_NO_PHYDRV},
},
[IMX8MQ] = {
.variant = IMX8MQ,
.gpr = "fsl,imx8mq-iomuxc-gpr",
+ .clk_names = {IMX6_CLKS_NO_PHYDRV, "pcie_aux"},
},
[IMX8MM] = {
.variant = IMX8MM,
.flags = IMX6_PCIE_FLAG_SUPPORTS_SUSPEND,
.gpr = "fsl,imx8mm-iomuxc-gpr",
+ .clk_names = {IMX6_CLKS_COMMON, "pcie_aux"},
},
[IMX8MP] = {
.variant = IMX8MP,
.flags = IMX6_PCIE_FLAG_SUPPORTS_SUSPEND,
.gpr = "fsl,imx8mp-iomuxc-gpr",
+ .clk_names = {IMX6_CLKS_COMMON, "pcie_aux"},
},
[IMX8MQ_EP] = {
.variant = IMX8MQ_EP,
.mode = DW_PCIE_EP_TYPE,
.gpr = "fsl,imx8mq-iomuxc-gpr",
+ .clk_names = {IMX6_CLKS_NO_PHYDRV, "pcie_aux"},
},
[IMX8MM_EP] = {
.variant = IMX8MM_EP,
.mode = DW_PCIE_EP_TYPE,
.gpr = "fsl,imx8mm-iomuxc-gpr",
+ .clk_names = {IMX6_CLKS_COMMON, "pcie_aux"},
},
[IMX8MP_EP] = {
.variant = IMX8MP_EP,
.mode = DW_PCIE_EP_TYPE,
.gpr = "fsl,imx8mp-iomuxc-gpr",
+ .clk_names = {IMX6_CLKS_COMMON, "pcie_aux"},
},
};

--
2.34.1