[PATCH v9 3/4] phy: freescale: imx8m-pcie: Refine i.MX8MM PCIe PHY driver

Hongxing Zhu hongxing.zhu at nxp.com
Thu Sep 29 01:18:15 PDT 2022


> -----Original Message-----
> From: Vinod Koul <vkoul at kernel.org>
> Sent: 2022年9月29日 14:32
> To: Hongxing Zhu <hongxing.zhu at nxp.com>
> Cc: p.zabel at pengutronix.de; l.stach at pengutronix.de; bhelgaas at google.com;
> lorenzo.pieralisi at arm.com; robh at kernel.org; shawnguo at kernel.org;
> alexander.stein at ew.tq-group.com; marex at denx.de; richard.leitner at linux.dev;
> linux-phy at lists.infradead.org; devicetree at vger.kernel.org;
> linux-pci at vger.kernel.org; linux-arm-kernel at lists.infradead.org;
> linux-kernel at vger.kernel.org; kernel at pengutronix.de; dl-linux-imx
> <linux-imx at nxp.com>
> Subject: Re: [PATCH v9 3/4] phy: freescale: imx8m-pcie: Refine i.MX8MM PCIe
> PHY driver
> 
> On 26-09-22, 14:41, Richard Zhu wrote:
> > To make it more flexible and easy to expand. Refine i.MX8MM PCIe PHY
> > driver.
> > - Use gpr compatible string to avoid the codes duplications when add
> >   another platform PCIe PHY support.
> > - Re-orange the codes to let it more flexible and easy to expand.
> > No functions changes basicly.
> >
> > Signed-off-by: Richard Zhu <hongxing.zhu at nxp.com>
> > Signed-off-by: Lucas Stach <l.stach at pengutronix.de>
> > Tested-by: Marek Vasut <marex at denx.de>
> > Tested-by: Richard Leitner <richard.leitner at skidata.com>
> > Tested-by: Alexander Stein <alexander.stein at ew.tq-group.com>
> > Reviewed-by: Lucas Stach <l.stach at pengutronix.de>
> > ---
> >  drivers/phy/freescale/phy-fsl-imx8m-pcie.c | 108
> > +++++++++++++--------
> >  1 file changed, 68 insertions(+), 40 deletions(-)
> >
> > diff --git a/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
> > b/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
> > index 2377ed307b53..9752818fe990 100644
> > --- a/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
> > +++ b/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
> > @@ -11,6 +11,7 @@
> >  #include <linux/mfd/syscon.h>
> >  #include <linux/mfd/syscon/imx7-iomuxc-gpr.h>
> >  #include <linux/module.h>
> > +#include <linux/of_device.h>
> >  #include <linux/phy/phy.h>
> >  #include <linux/platform_device.h>
> >  #include <linux/regmap.h>
> > @@ -45,6 +46,15 @@
> >  #define IMX8MM_GPR_PCIE_SSC_EN		BIT(16)
> >  #define IMX8MM_GPR_PCIE_AUX_EN_OVERRIDE	BIT(9)
> >
> > +enum imx8_pcie_phy_type {
> > +	IMX8MM,
> > +};
> > +
> > +struct imx8_pcie_phy_drvdata {
> > +	enum		imx8_pcie_phy_type variant;
> > +	const char	*gpr;
> > +};
> > +
> >  struct imx8_pcie_phy {
> >  	void __iomem		*base;
> >  	struct clk		*clk;
> > @@ -55,6 +65,7 @@ struct imx8_pcie_phy {
> >  	u32			tx_deemph_gen1;
> >  	u32			tx_deemph_gen2;
> >  	bool			clkreq_unused;
> > +	const struct imx8_pcie_phy_drvdata	*drvdata;
> >  };
> >
> >  static int imx8_pcie_phy_init(struct phy *phy) @@ -66,31 +77,17 @@
> > static int imx8_pcie_phy_init(struct phy *phy)
> >  	reset_control_assert(imx8_phy->reset);
> >
> >  	pad_mode = imx8_phy->refclk_pad_mode;
> > -	/* Set AUX_EN_OVERRIDE 1'b0, when the CLKREQ# isn't hooked */
> > -	regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
> > -			   IMX8MM_GPR_PCIE_AUX_EN_OVERRIDE,
> > -			   imx8_phy->clkreq_unused ?
> > -			   0 : IMX8MM_GPR_PCIE_AUX_EN_OVERRIDE);
> > -	regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
> > -			   IMX8MM_GPR_PCIE_AUX_EN,
> > -			   IMX8MM_GPR_PCIE_AUX_EN);
> > -	regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
> > -			   IMX8MM_GPR_PCIE_POWER_OFF, 0);
> > -	regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
> > -			   IMX8MM_GPR_PCIE_SSC_EN, 0);
> > -
> > -	regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
> > -			   IMX8MM_GPR_PCIE_REF_CLK_SEL,
> > -			   pad_mode == IMX8_PCIE_REFCLK_PAD_INPUT ?
> > -			   IMX8MM_GPR_PCIE_REF_CLK_EXT :
> > -			   IMX8MM_GPR_PCIE_REF_CLK_PLL);
> > -	usleep_range(100, 200);
> > -
> > -	/* Do the PHY common block reset */
> > -	regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
> > -			   IMX8MM_GPR_PCIE_CMN_RST,
> > -			   IMX8MM_GPR_PCIE_CMN_RST);
> > -	usleep_range(200, 500);
> > +	switch (imx8_phy->drvdata->variant) {
> > +	case IMX8MM:
> > +		/* Tune PHY de-emphasis setting to pass PCIe compliance. */
> > +		if (imx8_phy->tx_deemph_gen1)
> > +			writel(imx8_phy->tx_deemph_gen1,
> > +			       imx8_phy->base + PCIE_PHY_TRSV_REG5);
> > +		if (imx8_phy->tx_deemph_gen2)
> > +			writel(imx8_phy->tx_deemph_gen2,
> > +			       imx8_phy->base + PCIE_PHY_TRSV_REG6);
> > +		break;
> > +	}
> >
> >  	if (pad_mode == IMX8_PCIE_REFCLK_PAD_INPUT ||
> >  	    pad_mode == IMX8_PCIE_REFCLK_PAD_UNUSED) { @@ -118,15
> +115,37 @@
> > static int imx8_pcie_phy_init(struct phy *phy)
> >  		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG065);
> >  	}
> >
> > -	/* Tune PHY de-emphasis setting to pass PCIe compliance. */
> > -	if (imx8_phy->tx_deemph_gen1)
> > -		writel(imx8_phy->tx_deemph_gen1,
> > -		       imx8_phy->base + PCIE_PHY_TRSV_REG5);
> > -	if (imx8_phy->tx_deemph_gen2)
> > -		writel(imx8_phy->tx_deemph_gen2,
> > -		       imx8_phy->base + PCIE_PHY_TRSV_REG6);
> > +	/* Set AUX_EN_OVERRIDE 1'b0, when the CLKREQ# isn't hooked */
> > +	regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
> > +			   IMX8MM_GPR_PCIE_AUX_EN_OVERRIDE,
> > +			   imx8_phy->clkreq_unused ?
> > +			   0 : IMX8MM_GPR_PCIE_AUX_EN_OVERRIDE);
> > +	regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
> > +			   IMX8MM_GPR_PCIE_AUX_EN,
> > +			   IMX8MM_GPR_PCIE_AUX_EN);
> > +	regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
> > +			   IMX8MM_GPR_PCIE_POWER_OFF, 0);
> > +	regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
> > +			   IMX8MM_GPR_PCIE_SSC_EN, 0);
> >
> > -	reset_control_deassert(imx8_phy->reset);
> > +	regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
> > +			   IMX8MM_GPR_PCIE_REF_CLK_SEL,
> > +			   pad_mode == IMX8_PCIE_REFCLK_PAD_INPUT ?
> > +			   IMX8MM_GPR_PCIE_REF_CLK_EXT :
> > +			   IMX8MM_GPR_PCIE_REF_CLK_PLL);
> > +	usleep_range(100, 200);
> > +
> > +	/* Do the PHY common block reset */
> > +	regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
> > +			   IMX8MM_GPR_PCIE_CMN_RST,
> > +			   IMX8MM_GPR_PCIE_CMN_RST);
> > +
> > +	switch (imx8_phy->drvdata->variant) {
> > +	case IMX8MM:
> > +		reset_control_deassert(imx8_phy->reset);
> > +		usleep_range(200, 500);
> > +		break;
> > +	}
> >
> >  	/* Polling to check the phy is ready or not. */
> >  	ret = readl_poll_timeout(imx8_phy->base +
> > IMX8MM_PCIE_PHY_CMN_REG075, @@ -157,6 +176,19 @@ static const
> struct phy_ops imx8_pcie_phy_ops = {
> >  	.owner		= THIS_MODULE,
> >  };
> >
> > +static const struct imx8_pcie_phy_drvdata drvdata[] = {
> > +	[IMX8MM] = {
> > +		.variant = IMX8MM,
> > +		.gpr = "fsl,imx8mm-iomuxc-gpr",
> > +	},
> > +};
> 
> Pls drop the array...
> 
> static const struct imx8_pcie_phy_drvdata imx8mm_drvdata = {
>         .variant = IMX8MM,
>         .gpr = "fsl,imx8mm-iomuxc-gpr",
> };
> 

Okay, thanks.
> 
> 
> > +
> > +static const struct of_device_id imx8_pcie_phy_of_match[] = {
> > +	{.compatible = "fsl,imx8mm-pcie-phy", .data = &drvdata[IMX8MM], },
> 
> So this becomes:
> 
>         {.compatible = "fsl,imx8mm-pcie-phy", .data = &imx8mm_drvdata },
> 
> you can define new structs for newer SoCs

Okay, would follow this way. Thanks.

Best Regards
Richard Zhu

> 
> > +	{ },
> > +};
> > +MODULE_DEVICE_TABLE(of, imx8_pcie_phy_of_match);
> > +
> >  static int imx8_pcie_phy_probe(struct platform_device *pdev)  {
> >  	struct phy_provider *phy_provider;
> > @@ -169,6 +201,8 @@ static int imx8_pcie_phy_probe(struct
> platform_device *pdev)
> >  	if (!imx8_phy)
> >  		return -ENOMEM;
> >
> > +	imx8_phy->drvdata = of_device_get_match_data(dev);
> > +
> >  	/* get PHY refclk pad mode */
> >  	of_property_read_u32(np, "fsl,refclk-pad-mode",
> >  			     &imx8_phy->refclk_pad_mode);
> > @@ -194,7 +228,7 @@ static int imx8_pcie_phy_probe(struct
> > platform_device *pdev)
> >
> >  	/* Grab GPR config register range */
> >  	imx8_phy->iomuxc_gpr =
> > -		 syscon_regmap_lookup_by_compatible("fsl,imx6q-iomuxc-gpr");
> > +		 syscon_regmap_lookup_by_compatible(imx8_phy->drvdata->gpr);
> >  	if (IS_ERR(imx8_phy->iomuxc_gpr)) {
> >  		dev_err(dev, "unable to find iomuxc registers\n");
> >  		return PTR_ERR(imx8_phy->iomuxc_gpr); @@ -222,12 +256,6 @@
> static
> > int imx8_pcie_phy_probe(struct platform_device *pdev)
> >  	return PTR_ERR_OR_ZERO(phy_provider);  }
> >
> > -static const struct of_device_id imx8_pcie_phy_of_match[] = {
> > -	{.compatible = "fsl,imx8mm-pcie-phy",},
> > -	{ },
> > -};
> > -MODULE_DEVICE_TABLE(of, imx8_pcie_phy_of_match);
> > -
> >  static struct platform_driver imx8_pcie_phy_driver = {
> >  	.probe	= imx8_pcie_phy_probe,
> >  	.driver = {
> > --
> > 2.25.1
> 
> --
> ~Vinod


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