[PATCH v3 01/13] PCI: imx6: Simplify clock handling by using HAS_CLK_* bitmask

From: Frank Li
Date: Mon Dec 11 2023 - 16:59:35 EST


Refactors the clock handling logic in the imx6 PCI driver by adding
HAS_CLK_* bitmask define for drvdata::flags . Simplifies the code and makes
it more maintainable, as future additions of SOC support will only require
straightforward changes. The drvdata::flags and a bitmask ensures a cleaner
and more scalable switch-case structure for handling clocks.

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

Notes:
Change from v1 to v3
- none

drivers/pci/controller/dwc/pci-imx6.c | 84 +++++++++++++--------------
1 file changed, 42 insertions(+), 42 deletions(-)

diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
index 74703362aeec7..8a9b527934f80 100644
--- a/drivers/pci/controller/dwc/pci-imx6.c
+++ b/drivers/pci/controller/dwc/pci-imx6.c
@@ -60,6 +60,10 @@ enum imx6_pcie_variants {
#define IMX6_PCIE_FLAG_IMX6_PHY BIT(0)
#define IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE BIT(1)
#define IMX6_PCIE_FLAG_SUPPORTS_SUSPEND BIT(2)
+#define IMX6_PCIE_FLAG_HAS_CLK_INBOUND_AXI BIT(3)
+#define IMX6_PCIE_FLAG_HAS_CLK_AUX BIT(4)
+
+#define imx6_check_flag(pci, val) (pci->drvdata->flags & val)

struct imx6_pcie_drvdata {
enum imx6_pcie_variants variant;
@@ -550,19 +554,23 @@ 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:
+ if (imx6_check_flag(imx6_pcie, IMX6_PCIE_FLAG_HAS_CLK_INBOUND_AXI)) {
ret = clk_prepare_enable(imx6_pcie->pcie_inbound_axi);
- if (ret) {
- dev_err(dev, "unable to enable pcie_axi clock\n");
- break;
- }
+ if (ret)
+ return ret;
+ }

+ if (imx6_check_flag(imx6_pcie, IMX6_PCIE_FLAG_HAS_CLK_AUX)) {
+ ret = clk_prepare_enable(imx6_pcie->pcie_aux);
+ if (ret)
+ return ret;
+ }
+
+ switch (imx6_pcie->drvdata->variant) {
+ case IMX6SX:
regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
IMX6SX_GPR12_PCIE_TEST_POWERDOWN, 0);
break;
@@ -589,12 +597,6 @@ 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
@@ -614,10 +616,13 @@ 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:
+ if (imx6_check_flag(imx6_pcie, IMX6_PCIE_FLAG_HAS_CLK_INBOUND_AXI))
clk_disable_unprepare(imx6_pcie->pcie_inbound_axi);
- break;
+
+ if (imx6_check_flag(imx6_pcie, IMX6_PCIE_FLAG_HAS_CLK_AUX))
+ clk_disable_unprepare(imx6_pcie->pcie_aux);
+
+ switch (imx6_pcie->drvdata->variant) {
case IMX6QP:
case IMX6Q:
regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
@@ -631,14 +636,6 @@ 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;
}
@@ -1316,21 +1313,21 @@ static int imx6_pcie_probe(struct platform_device *pdev)
return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie),
"pcie clock source missing or invalid\n");

- switch (imx6_pcie->drvdata->variant) {
- case IMX6SX:
- imx6_pcie->pcie_inbound_axi = devm_clk_get(dev,
- "pcie_inbound_axi");
+ if (imx6_check_flag(imx6_pcie, IMX6_PCIE_FLAG_HAS_CLK_INBOUND_AXI)) {
+ 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:
+ dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie_inbound_axi),
+ "pcie_inbound_axi clock missing or invalid\n");
+ }
+
+ if (imx6_check_flag(imx6_pcie, IMX6_PCIE_FLAG_HAS_CLK_AUX)) {
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;
+ }
+
+ switch (imx6_pcie->drvdata->variant) {
case IMX7D:
if (dbi_base->start == IMX8MQ_PCIE2_BASE_ADDR)
imx6_pcie->controller_id = 1;
@@ -1353,10 +1350,6 @@ 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))
@@ -1482,7 +1475,8 @@ static const struct imx6_pcie_drvdata drvdata[] = {
.variant = IMX6SX,
.flags = IMX6_PCIE_FLAG_IMX6_PHY |
IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE |
- IMX6_PCIE_FLAG_SUPPORTS_SUSPEND,
+ IMX6_PCIE_FLAG_SUPPORTS_SUSPEND |
+ IMX6_PCIE_FLAG_HAS_CLK_INBOUND_AXI,
.gpr = "fsl,imx6q-iomuxc-gpr",
},
[IMX6QP] = {
@@ -1500,30 +1494,36 @@ static const struct imx6_pcie_drvdata drvdata[] = {
},
[IMX8MQ] = {
.variant = IMX8MQ,
+ .flags = IMX6_PCIE_FLAG_HAS_CLK_AUX,
.gpr = "fsl,imx8mq-iomuxc-gpr",
},
[IMX8MM] = {
.variant = IMX8MM,
- .flags = IMX6_PCIE_FLAG_SUPPORTS_SUSPEND,
+ .flags = IMX6_PCIE_FLAG_SUPPORTS_SUSPEND |
+ IMX6_PCIE_FLAG_HAS_CLK_AUX,
.gpr = "fsl,imx8mm-iomuxc-gpr",
},
[IMX8MP] = {
.variant = IMX8MP,
- .flags = IMX6_PCIE_FLAG_SUPPORTS_SUSPEND,
+ .flags = IMX6_PCIE_FLAG_SUPPORTS_SUSPEND |
+ IMX6_PCIE_FLAG_HAS_CLK_AUX,
.gpr = "fsl,imx8mp-iomuxc-gpr",
},
[IMX8MQ_EP] = {
.variant = IMX8MQ_EP,
+ .flags = IMX6_PCIE_FLAG_HAS_CLK_AUX,
.mode = DW_PCIE_EP_TYPE,
.gpr = "fsl,imx8mq-iomuxc-gpr",
},
[IMX8MM_EP] = {
.variant = IMX8MM_EP,
+ .flags = IMX6_PCIE_FLAG_HAS_CLK_AUX,
.mode = DW_PCIE_EP_TYPE,
.gpr = "fsl,imx8mm-iomuxc-gpr",
},
[IMX8MP_EP] = {
.variant = IMX8MP_EP,
+ .flags = IMX6_PCIE_FLAG_HAS_CLK_AUX,
.mode = DW_PCIE_EP_TYPE,
.gpr = "fsl,imx8mp-iomuxc-gpr",
},
--
2.34.1