Re: [PATCH v7 01/16] PCI: imx6: Simplify clock handling by using bulk_clk_*() function

Marco Felsch
2024-01-02T08:48:00Z

Hi Frank,

On 23-12-27, Frank Li wrote:
> Refactors the clock handling logic. Adds clk_names[] define in drvdata.
> Using clk_bulk*() api simplifies the code.

does this influence the clock enable/disable sequence ordering? Just
asking to avoid regressions on older platforms which may require some
sort of order (e.g. require clock-a before clock-b).

Regards,
Marco

> Signed-off-by: Frank Li <Frank.Li@nxp.com>
> ---
>
> Notes:
> Change from v4 to v5
> - update commit message
> - direct using clk name list, instead of macro
> - still keep caculate clk list count because sizeof return pre allocated
> array size.
>
> Change from v3 to v4
> - using clk_bulk_*() API
> Change from v1 to v3
> - none
>
> drivers/pci/controller/dwc/pci-imx6.c | 125 ++++++++------------------
> 1 file changed, 35 insertions(+), 90 deletions(-)
>
> diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
> index 74703362aeec7..50d9faaa17f71 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->clks[i].id = imx6_pcie->drvdata->clk_names[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");
> + /* 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");
> @@ -1477,6 +1412,7 @@ static const struct imx6_pcie_drvdata drvdata[] = {
> IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE,
> .dbi_length = 0x200,
> .gpr = "fsl,imx6q-iomuxc-gpr",
> + .clk_names = {"pcie_bus", "pcie", "pcie_phy"},
> },
> [IMX6SX] = {
> .variant = IMX6SX,
> @@ -1484,6 +1420,7 @@ 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 = {"pcie_bus", "pcie", "pcie_phy", "pcie_inbound_axi"},
> },
> [IMX6QP] = {
> .variant = IMX6QP,
> @@ -1492,40 +1429,48 @@ static const struct imx6_pcie_drvdata drvdata[] = {
> IMX6_PCIE_FLAG_SUPPORTS_SUSPEND,
> .dbi_length = 0x200,
> .gpr = "fsl,imx6q-iomuxc-gpr",
> + .clk_names = {"pcie_bus", "pcie", "pcie_phy"},
> },
> [IMX7D] = {
> .variant = IMX7D,
> .flags = IMX6_PCIE_FLAG_SUPPORTS_SUSPEND,
> .gpr = "fsl,imx7d-iomuxc-gpr",
> + .clk_names = {"pcie_bus", "pcie", "pcie_phy"},
> },
> [IMX8MQ] = {
> .variant = IMX8MQ,
> .gpr = "fsl,imx8mq-iomuxc-gpr",
> + .clk_names = {"pcie_bus", "pcie", "pcie_phy", "pcie_aux"},
> },
> [IMX8MM] = {
> .variant = IMX8MM,
> .flags = IMX6_PCIE_FLAG_SUPPORTS_SUSPEND,
> .gpr = "fsl,imx8mm-iomuxc-gpr",
> + .clk_names = {"pcie_bus", "pcie", "pcie_aux"},
> },
> [IMX8MP] = {
> .variant = IMX8MP,
> .flags = IMX6_PCIE_FLAG_SUPPORTS_SUSPEND,
> .gpr = "fsl,imx8mp-iomuxc-gpr",
> + .clk_names = {"pcie_bus", "pcie", "pcie_aux"},
> },
> [IMX8MQ_EP] = {
> .variant = IMX8MQ_EP,
> .mode = DW_PCIE_EP_TYPE,
> .gpr = "fsl,imx8mq-iomuxc-gpr",
> + .clk_names = {"pcie_bus", "pcie", "pcie_phy", "pcie_aux"},
> },
> [IMX8MM_EP] = {
> .variant = IMX8MM_EP,
> .mode = DW_PCIE_EP_TYPE,
> .gpr = "fsl,imx8mm-iomuxc-gpr",
> + .clk_names = {"pcie_bus", "pcie", "pcie_aux"},
> },
> [IMX8MP_EP] = {
> .variant = IMX8MP_EP,
> .mode = DW_PCIE_EP_TYPE,
> .gpr = "fsl,imx8mp-iomuxc-gpr",
> + .clk_names = {"pcie_bus", "pcie", "pcie_aux"},
> },
> };
>
> --
> 2.34.1
>
>
>