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

Frank Li
2024-01-03T17:03:05Z

On Tue, Jan 02, 2024 at 09:47:44AM +0100, Marco Felsch wrote:
> 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).

drvdata::clk_names is order of enble sequence. So far we have not found
the problem.

Frank Li
>
> 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
> >
> >
> >