[v2,3/7] phy: freescale: imx8m-pcie: Add iMX8MP PCIe PHY support

Commit Message

Hongxing Zhu March 7, 2022, 9:07 a.m. UTC

Add the i.MX8MP PCIe PHY support

Signed-off-by: Richard Zhu <[e-mail]>
---
 drivers/phy/freescale/phy-fsl-imx8m-pcie.c | 205 ++++++++++++++++-----
 1 file changed, 163 insertions(+), 42 deletions(-)

Comments

Lucas Stach March 8, 2022, 10:04 a.m. UTC | #1

Hi Richard,

Am Montag, dem 07.03.2022 um 17:07 +0800 schrieb Richard Zhu:
> Add the i.MX8MP PCIe PHY support
> 
> Signed-off-by: Richard Zhu <[e-mail]>
> ---
>  drivers/phy/freescale/phy-fsl-imx8m-pcie.c | 205 ++++++++++++++++-----
>  1 file changed, 163 insertions(+), 42 deletions(-)
> 
> diff --git a/drivers/phy/freescale/phy-fsl-imx8m-pcie.c b/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
> index 04b1aafb29f4..3d01da4323a6 100644
> --- a/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
> +++ b/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
> @@ -11,6 +11,8 @@
>  #include <linux/mfd/syscon.h>
>  #include <linux/mfd/syscon/imx7-iomuxc-gpr.h>
>  #include <linux/module.h>
> +#include <linux/of_address.h>
> +#include <linux/of_device.h>
>  #include <linux/phy/phy.h>
>  #include <linux/platform_device.h>
>  #include <linux/regmap.h>
> @@ -30,12 +32,10 @@
>  #define IMX8MM_PCIE_PHY_CMN_REG065	0x194
>  #define  ANA_AUX_RX_TERM		(BIT(7) | BIT(4))
>  #define  ANA_AUX_TX_LVL			GENMASK(3, 0)
> -#define IMX8MM_PCIE_PHY_CMN_REG75	0x1D4
> -#define  PCIE_PHY_CMN_REG75_PLL_DONE	0x3
> +#define IMX8MM_PCIE_PHY_CMN_REG075	0x1D4
> +#define  ANA_PLL_DONE			0x3
>  #define PCIE_PHY_TRSV_REG5		0x414
> -#define  PCIE_PHY_TRSV_REG5_GEN1_DEEMP	0x2D
>  #define PCIE_PHY_TRSV_REG6		0x418
> -#define  PCIE_PHY_TRSV_REG6_GEN2_DEEMP	0xF
>  
>  #define IMX8MM_GPR_PCIE_REF_CLK_SEL	GENMASK(25, 24)
>  #define IMX8MM_GPR_PCIE_REF_CLK_PLL	FIELD_PREP(IMX8MM_GPR_PCIE_REF_CLK_SEL, 0x3)
> @@ -46,16 +46,43 @@
>  #define IMX8MM_GPR_PCIE_SSC_EN		BIT(16)
>  #define IMX8MM_GPR_PCIE_AUX_EN_OVERRIDE	BIT(9)
>  
> +#define IMX8MP_GPR_REG0			0x0
> +#define IMX8MP_GPR_CLK_MOD_EN		BIT(0)
> +#define IMX8MP_GPR_PHY_APB_RST		BIT(4)
> +#define IMX8MP_GPR_PHY_INIT_RST		BIT(5)
> +#define IMX8MP_GPR_REG1			0x4
> +#define IMX8MP_GPR_PM_EN_CORE_CLK	BIT(0)
> +#define IMX8MP_GPR_PLL_LOCK		BIT(13)
> +#define IMX8MP_GPR_REG2			0x8
> +#define IMX8MP_GPR_P_PLL_MASK		GENMASK(5, 0)
> +#define IMX8MP_GPR_M_PLL_MASK		GENMASK(15, 6)
> +#define IMX8MP_GPR_S_PLL_MASK		GENMASK(18, 16)
> +#define IMX8MP_GPR_P_PLL		(0xc << 0)
> +#define IMX8MP_GPR_M_PLL		(0x320 << 6)
> +#define IMX8MP_GPR_S_PLL		(0x4 << 16)
> +#define IMX8MP_GPR_REG3			0xc
> +#define IMX8MP_GPR_PLL_CKE		BIT(17)
> +#define IMX8MP_GPR_PLL_RST		BIT(31)
> +
> +enum imx8_pcie_phy_type {
> +	IMX8MM,
> +	IMX8MP,
> +};
> +
>  struct imx8_pcie_phy {
>  	void __iomem		*base;
> +	struct device		*dev;
>  	struct clk		*clk;
>  	struct phy		*phy;
> +	struct regmap		*hsio_blk_ctrl;
>  	struct regmap		*iomuxc_gpr;
>  	struct reset_control	*reset;
> +	struct reset_control	*perst;
>  	u32			refclk_pad_mode;
>  	u32			tx_deemph_gen1;
>  	u32			tx_deemph_gen2;
>  	bool			clkreq_unused;
> +	enum imx8_pcie_phy_type	variant;
>  };
>  
>  static int imx8_pcie_phy_init(struct phy *phy)
> @@ -67,6 +94,87 @@ static int imx8_pcie_phy_init(struct phy *phy)
>  	reset_control_assert(imx8_phy->reset);
>  
>  	pad_mode = imx8_phy->refclk_pad_mode;
> +	switch (imx8_phy->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;
> +	case IMX8MP:
> +		reset_control_assert(imx8_phy->perst);
> +		/* Set P=12,M=800,S=4 and must set ICP=2'b01. */
> +		regmap_update_bits(imx8_phy->hsio_blk_ctrl, IMX8MP_GPR_REG2,
> +				   IMX8MP_GPR_P_PLL_MASK |
> +				   IMX8MP_GPR_M_PLL_MASK |
> +				   IMX8MP_GPR_S_PLL_MASK,
> +				   IMX8MP_GPR_P_PLL |
> +				   IMX8MP_GPR_M_PLL |
> +				   IMX8MP_GPR_S_PLL);
> +		/* wait greater than 1/F_FREF =1/2MHZ=0.5us */
> +		udelay(1);
> +
> +		regmap_update_bits(imx8_phy->hsio_blk_ctrl, IMX8MP_GPR_REG3,
> +				   IMX8MP_GPR_PLL_RST,
> +				   IMX8MP_GPR_PLL_RST);
> +		udelay(10);
> +
> +		/* Set 1 to pll_cke of GPR_REG3 */
> +		regmap_update_bits(imx8_phy->hsio_blk_ctrl, IMX8MP_GPR_REG3,
> +				   IMX8MP_GPR_PLL_CKE,
> +				   IMX8MP_GPR_PLL_CKE);
> +
> +		/* Lock time should be greater than 300cycle=300*0.5us=150us */
> +		ret = regmap_read_poll_timeout(imx8_phy->hsio_blk_ctrl,
> +					     IMX8MP_GPR_REG1, val,
> +					     val & IMX8MP_GPR_PLL_LOCK,
> +					     10, 1000);
> +		if (ret) {
> +			dev_err(imx8_phy->dev, "PCIe PLL lock timeout\n");
> +			return ret;
> +		}

As far as I understand the reference manual, this PLL is not exclusive
to the PCIe core, but can be used as a alternate reference clock for
the USB PHYs. I think we should not poke the PLL registers from the
PCIe PHY driver, but should make this PLL a real clock provided by the
HSIO blk-ctrl.

It's probably a good prove of concept for other clocks that need to be
provided by the blk-ctrls, as the audio blk-ctrl has much more of this
secondary clock controller functionality.

Do you want to give it a shot at integrating this into the blk-ctrl
driver, or should I take a look?

Regards,
Lucas

> +
> +		/* pcie_clock_module_en */
> +		regmap_update_bits(imx8_phy->hsio_blk_ctrl, IMX8MP_GPR_REG0,
> +				   IMX8MP_GPR_CLK_MOD_EN,
> +				   IMX8MP_GPR_CLK_MOD_EN);
> +		udelay(10);
> +
> +		reset_control_deassert(imx8_phy->reset);
> +		reset_control_deassert(imx8_phy->perst);
> +
> +		/* release pcie_phy_apb_reset and pcie_phy_init_resetn */
> +		regmap_update_bits(imx8_phy->hsio_blk_ctrl, IMX8MP_GPR_REG0,
> +				   IMX8MP_GPR_PHY_APB_RST |
> +				   IMX8MP_GPR_PHY_INIT_RST,
> +				   IMX8MP_GPR_PHY_APB_RST |
> +				   IMX8MP_GPR_PHY_INIT_RST);
> +		break;
> +	}
> +
> +	if (pad_mode == IMX8_PCIE_REFCLK_PAD_INPUT) {
> +		/* Configure the pad as input */
> +		val = readl(imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG061);
> +		writel(val & ~ANA_PLL_CLK_OUT_TO_EXT_IO_EN,
> +		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG061);
> +	} else if (pad_mode == IMX8_PCIE_REFCLK_PAD_OUTPUT) {
> +		/* Configure the PHY to output the refclock via pad */
> +		writel(ANA_PLL_CLK_OUT_TO_EXT_IO_EN,
> +		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG061);
> +		writel(ANA_PLL_CLK_OUT_TO_EXT_IO_SEL,
> +		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG062);
> +		writel(AUX_PLL_REFCLK_SEL_SYS_PLL,
> +		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG063);
> +		val = ANA_AUX_RX_TX_SEL_TX | ANA_AUX_TX_TERM;
> +		writel(val | ANA_AUX_RX_TERM_GND_EN,
> +		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG064);
> +		writel(ANA_AUX_RX_TERM | ANA_AUX_TX_LVL,
> +		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG065);
> +	}
> +
>  	/* 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,
> @@ -91,42 +199,30 @@ static int imx8_pcie_phy_init(struct phy *phy)
>  	regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
>  			   IMX8MM_GPR_PCIE_CMN_RST,
>  			   IMX8MM_GPR_PCIE_CMN_RST);
> -	usleep_range(200, 500);
>  
> -	if (pad_mode == IMX8_PCIE_REFCLK_PAD_INPUT) {
> -		/* Configure the pad as input */
> -		val = readl(imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG061);
> -		writel(val & ~ANA_PLL_CLK_OUT_TO_EXT_IO_EN,
> -		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG061);
> -	} else if (pad_mode == IMX8_PCIE_REFCLK_PAD_OUTPUT) {
> -		/* Configure the PHY to output the refclock via pad */
> -		writel(ANA_PLL_CLK_OUT_TO_EXT_IO_EN,
> -		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG061);
> -		writel(ANA_PLL_CLK_OUT_TO_EXT_IO_SEL,
> -		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG062);
> -		writel(AUX_PLL_REFCLK_SEL_SYS_PLL,
> -		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG063);
> -		val = ANA_AUX_RX_TX_SEL_TX | ANA_AUX_TX_TERM;
> -		writel(val | ANA_AUX_RX_TERM_GND_EN,
> -		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG064);
> -		writel(ANA_AUX_RX_TERM | ANA_AUX_TX_LVL,
> -		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG065);
> +	switch (imx8_phy->variant) {
> +	case IMX8MM:
> +		reset_control_deassert(imx8_phy->reset);
> +		usleep_range(200, 500);
> +		break;
> +
> +	case IMX8MP:
> +		/* wait for core_clk enabled */
> +		ret = regmap_read_poll_timeout(imx8_phy->hsio_blk_ctrl,
> +					     IMX8MP_GPR_REG1, val,
> +					     val & IMX8MP_GPR_PM_EN_CORE_CLK,
> +					     10, 20000);
> +		if (ret) {
> +			dev_err(imx8_phy->dev, "PCIe CORE CLK enable failed\n");
> +			return ret;
> +		}
> +
> +		break;
>  	}
>  
> -	/* 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);
> -
> -	reset_control_deassert(imx8_phy->reset);
> -
>  	/* Polling to check the phy is ready or not. */
> -	ret = readl_poll_timeout(imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG75,
> -				 val, val == PCIE_PHY_CMN_REG75_PLL_DONE,
> -				 10, 20000);
> +	ret = readl_poll_timeout(imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG075,
> +				 val, val == ANA_PLL_DONE, 10, 20000);
>  	return ret;
>  }
>  
> @@ -153,18 +249,33 @@ static const struct phy_ops imx8_pcie_phy_ops = {
>  	.owner		= THIS_MODULE,
>  };
>  
> +static const struct of_device_id imx8_pcie_phy_of_match[] = {
> +	{.compatible = "fsl,imx8mm-pcie-phy", .data = (void *)IMX8MM},
> +	{.compatible = "fsl,imx8mp-pcie-phy", .data = (void *)IMX8MP},
> +	{ },
> +};
> +MODULE_DEVICE_TABLE(of, imx8_pcie_phy_of_match);
> +
>  static int imx8_pcie_phy_probe(struct platform_device *pdev)
>  {
>  	struct phy_provider *phy_provider;
>  	struct device *dev = &pdev->dev;
> +	const struct of_device_id *of_id;
>  	struct device_node *np = dev->of_node;
>  	struct imx8_pcie_phy *imx8_phy;
>  	struct resource *res;
>  
> +	of_id = of_match_device(imx8_pcie_phy_of_match, dev);
> +	if (!of_id)
> +		return -EINVAL;
> +
>  	imx8_phy = devm_kzalloc(dev, sizeof(*imx8_phy), GFP_KERNEL);
>  	if (!imx8_phy)
>  		return -ENOMEM;
>  
> +	imx8_phy->dev = dev;
> +	imx8_phy->variant = (enum imx8_pcie_phy_type)of_id->data;
> +
>  	/* get PHY refclk pad mode */
>  	of_property_read_u32(np, "fsl,refclk-pad-mode",
>  			     &imx8_phy->refclk_pad_mode);
> @@ -201,6 +312,22 @@ static int imx8_pcie_phy_probe(struct platform_device *pdev)
>  		dev_err(dev, "Failed to get PCIEPHY reset control\n");
>  		return PTR_ERR(imx8_phy->reset);
>  	}
> +	if (imx8_phy->variant == IMX8MP) {
> +		/* Grab HSIO MIX config register range */
> +		imx8_phy->hsio_blk_ctrl =
> +			 syscon_regmap_lookup_by_compatible("fsl,imx8mp-hsio-blk-ctrl");
> +		if (IS_ERR(imx8_phy->hsio_blk_ctrl)) {
> +			dev_err(dev, "unable to find hsio mix registers\n");
> +			return PTR_ERR(imx8_phy->hsio_blk_ctrl);
> +		}
> +
> +		imx8_phy->perst =
> +			devm_reset_control_get_exclusive(dev, "perst");
> +		if (IS_ERR(imx8_phy->perst)) {
> +			dev_err(dev, "Failed to get PCIEPHY perst control\n");
> +			return PTR_ERR(imx8_phy->perst);
> +		}
> +	}
>  
>  	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>  	imx8_phy->base = devm_ioremap_resource(dev, res);
> @@ -218,12 +345,6 @@ 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 = {

Hongxing Zhu March 9, 2022, 6:05 a.m. UTC | #2

> -----Original Message-----
> From: Lucas Stach <[e-mail]>
> Sent: 2022年3月8日 18:05
> To: Hongxing Zhu <[e-mail]>; [e-mail];
> [e-mail]; [e-mail]; [e-mail];
> [e-mail]; [e-mail]; [e-mail]
> Cc: [e-mail]; [e-mail];
> [e-mail]; [e-mail];
> [e-mail]; [e-mail]; dl-linux-imx
> <[e-mail]>
> Subject: Re: [PATCH v2 3/7] phy: freescale: imx8m-pcie: Add iMX8MP PCIe PHY
> support
> 
> Hi Richard,
> 
> Am Montag, dem 07.03.2022 um 17:07 +0800 schrieb Richard Zhu:
> > Add the i.MX8MP PCIe PHY support
> >
> > Signed-off-by: Richard Zhu <[e-mail]>
> > ---
> >  drivers/phy/freescale/phy-fsl-imx8m-pcie.c | 205
> > ++++++++++++++++-----
> >  1 file changed, 163 insertions(+), 42 deletions(-)
> >
> > diff --git a/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
> > b/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
> > index 04b1aafb29f4..3d01da4323a6 100644
> > --- a/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
> > +++ b/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
> > @@ -11,6 +11,8 @@
> >  #include <linux/mfd/syscon.h>
> >  #include <linux/mfd/syscon/imx7-iomuxc-gpr.h>
> >  #include <linux/module.h>
> > +#include <linux/of_address.h>
> > +#include <linux/of_device.h>
> >  #include <linux/phy/phy.h>
> >  #include <linux/platform_device.h>
> >  #include <linux/regmap.h>
> > @@ -30,12 +32,10 @@
> >  #define IMX8MM_PCIE_PHY_CMN_REG065	0x194
> >  #define  ANA_AUX_RX_TERM		(BIT(7) | BIT(4))
> >  #define  ANA_AUX_TX_LVL			GENMASK(3, 0)
> > -#define IMX8MM_PCIE_PHY_CMN_REG75	0x1D4
> > -#define  PCIE_PHY_CMN_REG75_PLL_DONE	0x3
> > +#define IMX8MM_PCIE_PHY_CMN_REG075	0x1D4
> > +#define  ANA_PLL_DONE			0x3
> >  #define PCIE_PHY_TRSV_REG5		0x414
> > -#define  PCIE_PHY_TRSV_REG5_GEN1_DEEMP	0x2D
> >  #define PCIE_PHY_TRSV_REG6		0x418
> > -#define  PCIE_PHY_TRSV_REG6_GEN2_DEEMP	0xF
> >
> >  #define IMX8MM_GPR_PCIE_REF_CLK_SEL	GENMASK(25, 24)
> >  #define IMX8MM_GPR_PCIE_REF_CLK_PLL
> 	FIELD_PREP(IMX8MM_GPR_PCIE_REF_CLK_SEL, 0x3)
> > @@ -46,16 +46,43 @@
> >  #define IMX8MM_GPR_PCIE_SSC_EN		BIT(16)
> >  #define IMX8MM_GPR_PCIE_AUX_EN_OVERRIDE	BIT(9)
> >
> > +#define IMX8MP_GPR_REG0			0x0
> > +#define IMX8MP_GPR_CLK_MOD_EN		BIT(0)
> > +#define IMX8MP_GPR_PHY_APB_RST		BIT(4)
> > +#define IMX8MP_GPR_PHY_INIT_RST		BIT(5)
> > +#define IMX8MP_GPR_REG1			0x4
> > +#define IMX8MP_GPR_PM_EN_CORE_CLK	BIT(0)
> > +#define IMX8MP_GPR_PLL_LOCK		BIT(13)
> > +#define IMX8MP_GPR_REG2			0x8
> > +#define IMX8MP_GPR_P_PLL_MASK		GENMASK(5, 0)
> > +#define IMX8MP_GPR_M_PLL_MASK		GENMASK(15, 6)
> > +#define IMX8MP_GPR_S_PLL_MASK		GENMASK(18, 16)
> > +#define IMX8MP_GPR_P_PLL		(0xc << 0)
> > +#define IMX8MP_GPR_M_PLL		(0x320 << 6)
> > +#define IMX8MP_GPR_S_PLL		(0x4 << 16)
> > +#define IMX8MP_GPR_REG3			0xc
> > +#define IMX8MP_GPR_PLL_CKE		BIT(17)
> > +#define IMX8MP_GPR_PLL_RST		BIT(31)
> > +
> > +enum imx8_pcie_phy_type {
> > +	IMX8MM,
> > +	IMX8MP,
> > +};
> > +
> >  struct imx8_pcie_phy {
> >  	void __iomem		*base;
> > +	struct device		*dev;
> >  	struct clk		*clk;
> >  	struct phy		*phy;
> > +	struct regmap		*hsio_blk_ctrl;
> >  	struct regmap		*iomuxc_gpr;
> >  	struct reset_control	*reset;
> > +	struct reset_control	*perst;
> >  	u32			refclk_pad_mode;
> >  	u32			tx_deemph_gen1;
> >  	u32			tx_deemph_gen2;
> >  	bool			clkreq_unused;
> > +	enum imx8_pcie_phy_type	variant;
> >  };
> >
> >  static int imx8_pcie_phy_init(struct phy *phy) @@ -67,6 +94,87 @@
> > static int imx8_pcie_phy_init(struct phy *phy)
> >  	reset_control_assert(imx8_phy->reset);
> >
> >  	pad_mode = imx8_phy->refclk_pad_mode;
> > +	switch (imx8_phy->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;
> > +	case IMX8MP:
> > +		reset_control_assert(imx8_phy->perst);
> > +		/* Set P=12,M=800,S=4 and must set ICP=2'b01. */
> > +		regmap_update_bits(imx8_phy->hsio_blk_ctrl, IMX8MP_GPR_REG2,
> > +				   IMX8MP_GPR_P_PLL_MASK |
> > +				   IMX8MP_GPR_M_PLL_MASK |
> > +				   IMX8MP_GPR_S_PLL_MASK,
> > +				   IMX8MP_GPR_P_PLL |
> > +				   IMX8MP_GPR_M_PLL |
> > +				   IMX8MP_GPR_S_PLL);
> > +		/* wait greater than 1/F_FREF =1/2MHZ=0.5us */
> > +		udelay(1);
> > +
> > +		regmap_update_bits(imx8_phy->hsio_blk_ctrl, IMX8MP_GPR_REG3,
> > +				   IMX8MP_GPR_PLL_RST,
> > +				   IMX8MP_GPR_PLL_RST);
> > +		udelay(10);
> > +
> > +		/* Set 1 to pll_cke of GPR_REG3 */
> > +		regmap_update_bits(imx8_phy->hsio_blk_ctrl, IMX8MP_GPR_REG3,
> > +				   IMX8MP_GPR_PLL_CKE,
> > +				   IMX8MP_GPR_PLL_CKE);
> > +
> > +		/* Lock time should be greater than 300cycle=300*0.5us=150us */
> > +		ret = regmap_read_poll_timeout(imx8_phy->hsio_blk_ctrl,
> > +					     IMX8MP_GPR_REG1, val,
> > +					     val & IMX8MP_GPR_PLL_LOCK,
> > +					     10, 1000);
> > +		if (ret) {
> > +			dev_err(imx8_phy->dev, "PCIe PLL lock timeout\n");
> > +			return ret;
> > +		}
> 
> As far as I understand the reference manual, this PLL is not exclusive to the
> PCIe core, but can be used as a alternate reference clock for the USB PHYs. I
> think we should not poke the PLL registers from the PCIe PHY driver, but
> should make this PLL a real clock provided by the HSIO blk-ctrl.
> 
> It's probably a good prove of concept for other clocks that need to be provided
> by the blk-ctrls, as the audio blk-ctrl has much more of this secondary clock
> controller functionality.
> 
> Do you want to give it a shot at integrating this into the blk-ctrl driver, or
> should I take a look?
> 
Hi Lucas:
Thanks for your comments.
Yes, refer to the reference manual, most bits of the hsio-blk registers are
 defined for this PLL clock. But there are still two PCIe PHY reset bits,
 BIT(4) and BIT(5) of GPR_REG0.
Can all this bits and manipulations be encapsulated into one clock provided
 by blk-ctrls?

It's my pleasure that if you can take a look at it, and let blk-ctrls provide
 one clock for PCIe or USB modules.

Best Regards
Richard Zhu
> Regards,
> Lucas
> 
> > +
> > +		/* pcie_clock_module_en */
> > +		regmap_update_bits(imx8_phy->hsio_blk_ctrl, IMX8MP_GPR_REG0,
> > +				   IMX8MP_GPR_CLK_MOD_EN,
> > +				   IMX8MP_GPR_CLK_MOD_EN);
> > +		udelay(10);
> > +
> > +		reset_control_deassert(imx8_phy->reset);
> > +		reset_control_deassert(imx8_phy->perst);
> > +
> > +		/* release pcie_phy_apb_reset and pcie_phy_init_resetn */
> > +		regmap_update_bits(imx8_phy->hsio_blk_ctrl, IMX8MP_GPR_REG0,
> > +				   IMX8MP_GPR_PHY_APB_RST |
> > +				   IMX8MP_GPR_PHY_INIT_RST,
> > +				   IMX8MP_GPR_PHY_APB_RST |
> > +				   IMX8MP_GPR_PHY_INIT_RST);
> > +		break;
> > +	}
> > +
> > +	if (pad_mode == IMX8_PCIE_REFCLK_PAD_INPUT) {
> > +		/* Configure the pad as input */
> > +		val = readl(imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG061);
> > +		writel(val & ~ANA_PLL_CLK_OUT_TO_EXT_IO_EN,
> > +		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG061);
> > +	} else if (pad_mode == IMX8_PCIE_REFCLK_PAD_OUTPUT) {
> > +		/* Configure the PHY to output the refclock via pad */
> > +		writel(ANA_PLL_CLK_OUT_TO_EXT_IO_EN,
> > +		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG061);
> > +		writel(ANA_PLL_CLK_OUT_TO_EXT_IO_SEL,
> > +		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG062);
> > +		writel(AUX_PLL_REFCLK_SEL_SYS_PLL,
> > +		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG063);
> > +		val = ANA_AUX_RX_TX_SEL_TX | ANA_AUX_TX_TERM;
> > +		writel(val | ANA_AUX_RX_TERM_GND_EN,
> > +		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG064);
> > +		writel(ANA_AUX_RX_TERM | ANA_AUX_TX_LVL,
> > +		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG065);
> > +	}
> > +
> >  	/* 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, @@ -91,42
> +199,30 @@ static
> > int imx8_pcie_phy_init(struct phy *phy)
> >  	regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
> >  			   IMX8MM_GPR_PCIE_CMN_RST,
> >  			   IMX8MM_GPR_PCIE_CMN_RST);
> > -	usleep_range(200, 500);
> >
> > -	if (pad_mode == IMX8_PCIE_REFCLK_PAD_INPUT) {
> > -		/* Configure the pad as input */
> > -		val = readl(imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG061);
> > -		writel(val & ~ANA_PLL_CLK_OUT_TO_EXT_IO_EN,
> > -		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG061);
> > -	} else if (pad_mode == IMX8_PCIE_REFCLK_PAD_OUTPUT) {
> > -		/* Configure the PHY to output the refclock via pad */
> > -		writel(ANA_PLL_CLK_OUT_TO_EXT_IO_EN,
> > -		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG061);
> > -		writel(ANA_PLL_CLK_OUT_TO_EXT_IO_SEL,
> > -		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG062);
> > -		writel(AUX_PLL_REFCLK_SEL_SYS_PLL,
> > -		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG063);
> > -		val = ANA_AUX_RX_TX_SEL_TX | ANA_AUX_TX_TERM;
> > -		writel(val | ANA_AUX_RX_TERM_GND_EN,
> > -		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG064);
> > -		writel(ANA_AUX_RX_TERM | ANA_AUX_TX_LVL,
> > -		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG065);
> > +	switch (imx8_phy->variant) {
> > +	case IMX8MM:
> > +		reset_control_deassert(imx8_phy->reset);
> > +		usleep_range(200, 500);
> > +		break;
> > +
> > +	case IMX8MP:
> > +		/* wait for core_clk enabled */
> > +		ret = regmap_read_poll_timeout(imx8_phy->hsio_blk_ctrl,
> > +					     IMX8MP_GPR_REG1, val,
> > +					     val & IMX8MP_GPR_PM_EN_CORE_CLK,
> > +					     10, 20000);
> > +		if (ret) {
> > +			dev_err(imx8_phy->dev, "PCIe CORE CLK enable failed\n");
> > +			return ret;
> > +		}
> > +
> > +		break;
> >  	}
> >
> > -	/* 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);
> > -
> > -	reset_control_deassert(imx8_phy->reset);
> > -
> >  	/* Polling to check the phy is ready or not. */
> > -	ret = readl_poll_timeout(imx8_phy->base +
> IMX8MM_PCIE_PHY_CMN_REG75,
> > -				 val, val == PCIE_PHY_CMN_REG75_PLL_DONE,
> > -				 10, 20000);
> > +	ret = readl_poll_timeout(imx8_phy->base +
> IMX8MM_PCIE_PHY_CMN_REG075,
> > +				 val, val == ANA_PLL_DONE, 10, 20000);
> >  	return ret;
> >  }
> >
> > @@ -153,18 +249,33 @@ static const struct phy_ops imx8_pcie_phy_ops =
> {
> >  	.owner		= THIS_MODULE,
> >  };
> >
> > +static const struct of_device_id imx8_pcie_phy_of_match[] = {
> > +	{.compatible = "fsl,imx8mm-pcie-phy", .data = (void *)IMX8MM},
> > +	{.compatible = "fsl,imx8mp-pcie-phy", .data = (void *)IMX8MP},
> > +	{ },
> > +};
> > +MODULE_DEVICE_TABLE(of, imx8_pcie_phy_of_match);
> > +
> >  static int imx8_pcie_phy_probe(struct platform_device *pdev)  {
> >  	struct phy_provider *phy_provider;
> >  	struct device *dev = &pdev->dev;
> > +	const struct of_device_id *of_id;
> >  	struct device_node *np = dev->of_node;
> >  	struct imx8_pcie_phy *imx8_phy;
> >  	struct resource *res;
> >
> > +	of_id = of_match_device(imx8_pcie_phy_of_match, dev);
> > +	if (!of_id)
> > +		return -EINVAL;
> > +
> >  	imx8_phy = devm_kzalloc(dev, sizeof(*imx8_phy), GFP_KERNEL);
> >  	if (!imx8_phy)
> >  		return -ENOMEM;
> >
> > +	imx8_phy->dev = dev;
> > +	imx8_phy->variant = (enum imx8_pcie_phy_type)of_id->data;
> > +
> >  	/* get PHY refclk pad mode */
> >  	of_property_read_u32(np, "fsl,refclk-pad-mode",
> >  			     &imx8_phy->refclk_pad_mode);
> > @@ -201,6 +312,22 @@ static int imx8_pcie_phy_probe(struct
> platform_device *pdev)
> >  		dev_err(dev, "Failed to get PCIEPHY reset control\n");
> >  		return PTR_ERR(imx8_phy->reset);
> >  	}
> > +	if (imx8_phy->variant == IMX8MP) {
> > +		/* Grab HSIO MIX config register range */
> > +		imx8_phy->hsio_blk_ctrl =
> > +
> syscon_regmap_lookup_by_compatible("fsl,imx8mp-hsio-blk-ctrl");
> > +		if (IS_ERR(imx8_phy->hsio_blk_ctrl)) {
> > +			dev_err(dev, "unable to find hsio mix registers\n");
> > +			return PTR_ERR(imx8_phy->hsio_blk_ctrl);
> > +		}
> > +
> > +		imx8_phy->perst =
> > +			devm_reset_control_get_exclusive(dev, "perst");
> > +		if (IS_ERR(imx8_phy->perst)) {
> > +			dev_err(dev, "Failed to get PCIEPHY perst control\n");
> > +			return PTR_ERR(imx8_phy->perst);
> > +		}
> > +	}
> >
> >  	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> >  	imx8_phy->base = devm_ioremap_resource(dev, res); @@ -218,12 +345,6
> > @@ 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 = {
>

Lucas Stach April 14, 2022, 8:58 p.m. UTC | #3

Am Montag, dem 07.03.2022 um 17:07 +0800 schrieb Richard Zhu:
> Add the i.MX8MP PCIe PHY support
> 
> Signed-off-by: Richard Zhu <[e-mail]>
> ---
>  drivers/phy/freescale/phy-fsl-imx8m-pcie.c | 205 ++++++++++++++++-----
>  1 file changed, 163 insertions(+), 42 deletions(-)
> 
> diff --git a/drivers/phy/freescale/phy-fsl-imx8m-pcie.c b/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
> index 04b1aafb29f4..3d01da4323a6 100644
> --- a/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
> +++ b/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
> @@ -11,6 +11,8 @@
>  #include <linux/mfd/syscon.h>
>  #include <linux/mfd/syscon/imx7-iomuxc-gpr.h>
>  #include <linux/module.h>
> +#include <linux/of_address.h>
> +#include <linux/of_device.h>
>  #include <linux/phy/phy.h>
>  #include <linux/platform_device.h>
>  #include <linux/regmap.h>
> @@ -30,12 +32,10 @@
>  #define IMX8MM_PCIE_PHY_CMN_REG065	0x194
>  #define  ANA_AUX_RX_TERM		(BIT(7) | BIT(4))
>  #define  ANA_AUX_TX_LVL			GENMASK(3, 0)
> -#define IMX8MM_PCIE_PHY_CMN_REG75	0x1D4
> -#define  PCIE_PHY_CMN_REG75_PLL_DONE	0x3
> +#define IMX8MM_PCIE_PHY_CMN_REG075	0x1D4
> +#define  ANA_PLL_DONE			0x3

Why do you drop the register prefix from the name here?

>  #define PCIE_PHY_TRSV_REG5		0x414
> -#define  PCIE_PHY_TRSV_REG5_GEN1_DEEMP	0x2D
>  #define PCIE_PHY_TRSV_REG6		0x418
> -#define  PCIE_PHY_TRSV_REG6_GEN2_DEEMP	0xF
>  
>  #define IMX8MM_GPR_PCIE_REF_CLK_SEL	GENMASK(25, 24)
>  #define IMX8MM_GPR_PCIE_REF_CLK_PLL	FIELD_PREP(IMX8MM_GPR_PCIE_REF_CLK_SEL, 0x3)
> @@ -46,16 +46,43 @@
>  #define IMX8MM_GPR_PCIE_SSC_EN		BIT(16)
>  #define IMX8MM_GPR_PCIE_AUX_EN_OVERRIDE	BIT(9)
>  
> +#define IMX8MP_GPR_REG0			0x0
> +#define IMX8MP_GPR_CLK_MOD_EN		BIT(0)
> +#define IMX8MP_GPR_PHY_APB_RST		BIT(4)
> +#define IMX8MP_GPR_PHY_INIT_RST		BIT(5)
> +#define IMX8MP_GPR_REG1			0x4
> +#define IMX8MP_GPR_PM_EN_CORE_CLK	BIT(0)
> +#define IMX8MP_GPR_PLL_LOCK		BIT(13)
> +#define IMX8MP_GPR_REG2			0x8
> +#define IMX8MP_GPR_P_PLL_MASK		GENMASK(5, 0)
> +#define IMX8MP_GPR_M_PLL_MASK		GENMASK(15, 6)
> +#define IMX8MP_GPR_S_PLL_MASK		GENMASK(18, 16)
> +#define IMX8MP_GPR_P_PLL		(0xc << 0)
> +#define IMX8MP_GPR_M_PLL		(0x320 << 6)
> +#define IMX8MP_GPR_S_PLL		(0x4 << 16)
> +#define IMX8MP_GPR_REG3			0xc
> +#define IMX8MP_GPR_PLL_CKE		BIT(17)
> +#define IMX8MP_GPR_PLL_RST		BIT(31)
> +
> +enum imx8_pcie_phy_type {
> +	IMX8MM,
> +	IMX8MP,
> +};
> +
>  struct imx8_pcie_phy {
>  	void __iomem		*base;
> +	struct device		*dev;
>  	struct clk		*clk;
>  	struct phy		*phy;
> +	struct regmap		*hsio_blk_ctrl;
>  	struct regmap		*iomuxc_gpr;
>  	struct reset_control	*reset;
> +	struct reset_control	*perst;
>  	u32			refclk_pad_mode;
>  	u32			tx_deemph_gen1;
>  	u32			tx_deemph_gen2;
>  	bool			clkreq_unused;
> +	enum imx8_pcie_phy_type	variant;
>  };
>  
>  static int imx8_pcie_phy_init(struct phy *phy)
> @@ -67,6 +94,87 @@ static int imx8_pcie_phy_init(struct phy *phy)
>  	reset_control_assert(imx8_phy->reset);
>  
>  	pad_mode = imx8_phy->refclk_pad_mode;
> +	switch (imx8_phy->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;
> +	case IMX8MP:
> +		reset_control_assert(imx8_phy->perst);

Could you tell us something more about this reset. What exactly is it
resetting. Do we really need to assert it before starting the HSIO PLL?
AFAICS the PLL should be pretty much independent of the PHY.

Do we need to enable this PLL when the PHY gets an external refclock? I
couldn't test it yet, but I suspect that the HSIO PLL is only needed as
an internal reference, when the i.MX8MP is the refclock source, either
through the PHY pads or via a clkout from the PLL.
 
> +		/* Set P=12,M=800,S=4 and must set ICP=2'b01. */
> +		regmap_update_bits(imx8_phy->hsio_blk_ctrl, IMX8MP_GPR_REG2,
> +				   IMX8MP_GPR_P_PLL_MASK |
> +				   IMX8MP_GPR_M_PLL_MASK |
> +				   IMX8MP_GPR_S_PLL_MASK,
> +				   IMX8MP_GPR_P_PLL |
> +				   IMX8MP_GPR_M_PLL |
> +				   IMX8MP_GPR_S_PLL);
> +		/* wait greater than 1/F_FREF =1/2MHZ=0.5us */
> +		udelay(1);
> +
> +		regmap_update_bits(imx8_phy->hsio_blk_ctrl, IMX8MP_GPR_REG3,
> +				   IMX8MP_GPR_PLL_RST,
> +				   IMX8MP_GPR_PLL_RST);
> +		udelay(10);
> +
> +		/* Set 1 to pll_cke of GPR_REG3 */
> +		regmap_update_bits(imx8_phy->hsio_blk_ctrl, IMX8MP_GPR_REG3,
> +				   IMX8MP_GPR_PLL_CKE,
> +				   IMX8MP_GPR_PLL_CKE);
> +
> +		/* Lock time should be greater than 300cycle=300*0.5us=150us */
> +		ret = regmap_read_poll_timeout(imx8_phy->hsio_blk_ctrl,
> +					     IMX8MP_GPR_REG1, val,
> +					     val & IMX8MP_GPR_PLL_LOCK,
> +					     10, 1000);
> +		if (ret) {
> +			dev_err(imx8_phy->dev, "PCIe PLL lock timeout\n");
> +			return ret;
> +		}
> +
> +		/* pcie_clock_module_en */
> +		regmap_update_bits(imx8_phy->hsio_blk_ctrl, IMX8MP_GPR_REG0,
> +				   IMX8MP_GPR_CLK_MOD_EN,
> +				   IMX8MP_GPR_CLK_MOD_EN);

You shouldn't need to touch this bit. The HSIO blk-ctrl already enables
this bit when the PCIe power-domain is powered up.

> +		udelay(10);
> +
> +		reset_control_deassert(imx8_phy->reset);
> +		reset_control_deassert(imx8_phy->perst);
> +
> +		/* release pcie_phy_apb_reset and pcie_phy_init_resetn */
> +		regmap_update_bits(imx8_phy->hsio_blk_ctrl, IMX8MP_GPR_REG0,
> +				   IMX8MP_GPR_PHY_APB_RST |
> +				   IMX8MP_GPR_PHY_INIT_RST,
> +				   IMX8MP_GPR_PHY_APB_RST |
> +				   IMX8MP_GPR_PHY_INIT_RST);

Not sure about those yet. We might want to toggle them via a virtual PD
in the HSIO blk-ctrl.

> +		break;
> +	}
> +
> +	if (pad_mode == IMX8_PCIE_REFCLK_PAD_INPUT) {
> +		/* Configure the pad as input */
> +		val = readl(imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG061);
> +		writel(val & ~ANA_PLL_CLK_OUT_TO_EXT_IO_EN,
> +		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG061);
> +	} else if (pad_mode == IMX8_PCIE_REFCLK_PAD_OUTPUT) {
> +		/* Configure the PHY to output the refclock via pad */
> +		writel(ANA_PLL_CLK_OUT_TO_EXT_IO_EN,
> +		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG061);
> +		writel(ANA_PLL_CLK_OUT_TO_EXT_IO_SEL,
> +		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG062);
> +		writel(AUX_PLL_REFCLK_SEL_SYS_PLL,
> +		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG063);
> +		val = ANA_AUX_RX_TX_SEL_TX | ANA_AUX_TX_TERM;
> +		writel(val | ANA_AUX_RX_TERM_GND_EN,
> +		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG064);
> +		writel(ANA_AUX_RX_TERM | ANA_AUX_TX_LVL,
> +		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG065);
> +	}
> +
>  	/* 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,
> @@ -91,42 +199,30 @@ static int imx8_pcie_phy_init(struct phy *phy)
>  	regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
>  			   IMX8MM_GPR_PCIE_CMN_RST,
>  			   IMX8MM_GPR_PCIE_CMN_RST);
> -	usleep_range(200, 500);
>  
> -	if (pad_mode == IMX8_PCIE_REFCLK_PAD_INPUT) {
> -		/* Configure the pad as input */
> -		val = readl(imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG061);
> -		writel(val & ~ANA_PLL_CLK_OUT_TO_EXT_IO_EN,
> -		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG061);
> -	} else if (pad_mode == IMX8_PCIE_REFCLK_PAD_OUTPUT) {
> -		/* Configure the PHY to output the refclock via pad */
> -		writel(ANA_PLL_CLK_OUT_TO_EXT_IO_EN,
> -		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG061);
> -		writel(ANA_PLL_CLK_OUT_TO_EXT_IO_SEL,
> -		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG062);
> -		writel(AUX_PLL_REFCLK_SEL_SYS_PLL,
> -		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG063);
> -		val = ANA_AUX_RX_TX_SEL_TX | ANA_AUX_TX_TERM;
> -		writel(val | ANA_AUX_RX_TERM_GND_EN,
> -		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG064);
> -		writel(ANA_AUX_RX_TERM | ANA_AUX_TX_LVL,
> -		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG065);
> +	switch (imx8_phy->variant) {
> +	case IMX8MM:
> +		reset_control_deassert(imx8_phy->reset);
> +		usleep_range(200, 500);
> +		break;
> +
> +	case IMX8MP:
> +		/* wait for core_clk enabled */
> +		ret = regmap_read_poll_timeout(imx8_phy->hsio_blk_ctrl,
> +					     IMX8MP_GPR_REG1, val,
> +					     val & IMX8MP_GPR_PM_EN_CORE_CLK,
> +					     10, 20000);
> +		if (ret) {
> +			dev_err(imx8_phy->dev, "PCIe CORE CLK enable failed\n");
> +			return ret;
> +		}
> +
> +		break;
>  	}
>  
> -	/* 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);
> -
> -	reset_control_deassert(imx8_phy->reset);
> -
>  	/* Polling to check the phy is ready or not. */
> -	ret = readl_poll_timeout(imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG75,
> -				 val, val == PCIE_PHY_CMN_REG75_PLL_DONE,
> -				 10, 20000);
> +	ret = readl_poll_timeout(imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG075,
> +				 val, val == ANA_PLL_DONE, 10, 20000);
>  	return ret;
>  }
>  
> @@ -153,18 +249,33 @@ static const struct phy_ops imx8_pcie_phy_ops = {
>  	.owner		= THIS_MODULE,
>  };
>  
> +static const struct of_device_id imx8_pcie_phy_of_match[] = {
> +	{.compatible = "fsl,imx8mm-pcie-phy", .data = (void *)IMX8MM},
> +	{.compatible = "fsl,imx8mp-pcie-phy", .data = (void *)IMX8MP},
> +	{ },
> +};
> +MODULE_DEVICE_TABLE(of, imx8_pcie_phy_of_match);
> +
>  static int imx8_pcie_phy_probe(struct platform_device *pdev)
>  {
>  	struct phy_provider *phy_provider;
>  	struct device *dev = &pdev->dev;
> +	const struct of_device_id *of_id;
>  	struct device_node *np = dev->of_node;
>  	struct imx8_pcie_phy *imx8_phy;
>  	struct resource *res;
>  
> +	of_id = of_match_device(imx8_pcie_phy_of_match, dev);
> +	if (!of_id)
> +		return -EINVAL;
> +
>  	imx8_phy = devm_kzalloc(dev, sizeof(*imx8_phy), GFP_KERNEL);
>  	if (!imx8_phy)
>  		return -ENOMEM;
>  
> +	imx8_phy->dev = dev;
> +	imx8_phy->variant = (enum imx8_pcie_phy_type)of_id->data;
> +
>  	/* get PHY refclk pad mode */
>  	of_property_read_u32(np, "fsl,refclk-pad-mode",
>  			     &imx8_phy->refclk_pad_mode);
> @@ -201,6 +312,22 @@ static int imx8_pcie_phy_probe(struct platform_device *pdev)
>  		dev_err(dev, "Failed to get PCIEPHY reset control\n");
>  		return PTR_ERR(imx8_phy->reset);
>  	}
> +	if (imx8_phy->variant == IMX8MP) {
> +		/* Grab HSIO MIX config register range */
> +		imx8_phy->hsio_blk_ctrl =
> +			 syscon_regmap_lookup_by_compatible("fsl,imx8mp-hsio-blk-ctrl");
> +		if (IS_ERR(imx8_phy->hsio_blk_ctrl)) {
> +			dev_err(dev, "unable to find hsio mix registers\n");
> +			return PTR_ERR(imx8_phy->hsio_blk_ctrl);
> +		}
> +
> +		imx8_phy->perst =
> +			devm_reset_control_get_exclusive(dev, "perst");
> +		if (IS_ERR(imx8_phy->perst)) {
> +			dev_err(dev, "Failed to get PCIEPHY perst control\n");
> +			return PTR_ERR(imx8_phy->perst);
> +		}
> +	}

I still hope that we can push all the HSIO blk-ctrl register access
into the blk-ctrl driver, by adding the PLL as a clock there and maybe
abstracting the PHY reset bits a virtual PD for the PHY, so we don't
need this direct access in the PHY driver. Depends a bit on weather we
are able to get the sequencing right when splitting things across
multiple drivers.

Regards,
Lucas

>  
>  	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>  	imx8_phy->base = devm_ioremap_resource(dev, res);
> @@ -218,12 +345,6 @@ 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 = {

Hongxing Zhu April 18, 2022, 4:55 a.m. UTC | #4

> -----Original Message-----
> From: Lucas Stach <[e-mail]>
> Sent: 2022年4月15日 4:59
> To: Hongxing Zhu <[e-mail]>; [e-mail];
> [e-mail]; [e-mail]; [e-mail];
> [e-mail]; [e-mail]; [e-mail]
> Cc: [e-mail]; [e-mail];
> [e-mail]; [e-mail];
> [e-mail]; [e-mail]; dl-linux-imx
> <[e-mail]>
> Subject: Re: [PATCH v2 3/7] phy: freescale: imx8m-pcie: Add iMX8MP PCIe PHY
> support
> 
> Am Montag, dem 07.03.2022 um 17:07 +0800 schrieb Richard Zhu:
> > Add the i.MX8MP PCIe PHY support
> >
> > Signed-off-by: Richard Zhu <[e-mail]>
> > ---
> >  drivers/phy/freescale/phy-fsl-imx8m-pcie.c | 205
> > ++++++++++++++++-----
> >  1 file changed, 163 insertions(+), 42 deletions(-)
> >
> > diff --git a/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
> > b/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
> > index 04b1aafb29f4..3d01da4323a6 100644
> > --- a/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
> > +++ b/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
> > @@ -11,6 +11,8 @@
> >  #include <linux/mfd/syscon.h>
> >  #include <linux/mfd/syscon/imx7-iomuxc-gpr.h>
> >  #include <linux/module.h>
> > +#include <linux/of_address.h>
> > +#include <linux/of_device.h>
> >  #include <linux/phy/phy.h>
> >  #include <linux/platform_device.h>
> >  #include <linux/regmap.h>
> > @@ -30,12 +32,10 @@
> >  #define IMX8MM_PCIE_PHY_CMN_REG065	0x194
> >  #define  ANA_AUX_RX_TERM		(BIT(7) | BIT(4))
> >  #define  ANA_AUX_TX_LVL			GENMASK(3, 0)
> > -#define IMX8MM_PCIE_PHY_CMN_REG75	0x1D4
> > -#define  PCIE_PHY_CMN_REG75_PLL_DONE	0x3
> > +#define IMX8MM_PCIE_PHY_CMN_REG075	0x1D4
> > +#define  ANA_PLL_DONE			0x3
> 
> Why do you drop the register prefix from the name here?
To prevent the codes from exceeding the 80 columns and align with the other
 bit definitions, drop the prefix and keep the bit definitions as short as
 possible.

> 
> >  #define PCIE_PHY_TRSV_REG5		0x414
> > -#define  PCIE_PHY_TRSV_REG5_GEN1_DEEMP	0x2D
> >  #define PCIE_PHY_TRSV_REG6		0x418
> > -#define  PCIE_PHY_TRSV_REG6_GEN2_DEEMP	0xF
> >
> >  #define IMX8MM_GPR_PCIE_REF_CLK_SEL	GENMASK(25, 24)
> >  #define IMX8MM_GPR_PCIE_REF_CLK_PLL
> 	FIELD_PREP(IMX8MM_GPR_PCIE_REF_CLK_SEL, 0x3)
> > @@ -46,16 +46,43 @@
> >  #define IMX8MM_GPR_PCIE_SSC_EN		BIT(16)
> >  #define IMX8MM_GPR_PCIE_AUX_EN_OVERRIDE	BIT(9)
> >
> > +#define IMX8MP_GPR_REG0			0x0
> > +#define IMX8MP_GPR_CLK_MOD_EN		BIT(0)
> > +#define IMX8MP_GPR_PHY_APB_RST		BIT(4)
> > +#define IMX8MP_GPR_PHY_INIT_RST		BIT(5)
> > +#define IMX8MP_GPR_REG1			0x4
> > +#define IMX8MP_GPR_PM_EN_CORE_CLK	BIT(0)
> > +#define IMX8MP_GPR_PLL_LOCK		BIT(13)
> > +#define IMX8MP_GPR_REG2			0x8
> > +#define IMX8MP_GPR_P_PLL_MASK		GENMASK(5, 0)
> > +#define IMX8MP_GPR_M_PLL_MASK		GENMASK(15, 6)
> > +#define IMX8MP_GPR_S_PLL_MASK		GENMASK(18, 16)
> > +#define IMX8MP_GPR_P_PLL		(0xc << 0)
> > +#define IMX8MP_GPR_M_PLL		(0x320 << 6)
> > +#define IMX8MP_GPR_S_PLL		(0x4 << 16)
> > +#define IMX8MP_GPR_REG3			0xc
> > +#define IMX8MP_GPR_PLL_CKE		BIT(17)
> > +#define IMX8MP_GPR_PLL_RST		BIT(31)
> > +
> > +enum imx8_pcie_phy_type {
> > +	IMX8MM,
> > +	IMX8MP,
> > +};
> > +
> >  struct imx8_pcie_phy {
> >  	void __iomem		*base;
> > +	struct device		*dev;
> >  	struct clk		*clk;
> >  	struct phy		*phy;
> > +	struct regmap		*hsio_blk_ctrl;
> >  	struct regmap		*iomuxc_gpr;
> >  	struct reset_control	*reset;
> > +	struct reset_control	*perst;
> >  	u32			refclk_pad_mode;
> >  	u32			tx_deemph_gen1;
> >  	u32			tx_deemph_gen2;
> >  	bool			clkreq_unused;
> > +	enum imx8_pcie_phy_type	variant;
> >  };
> >
> >  static int imx8_pcie_phy_init(struct phy *phy) @@ -67,6 +94,87 @@
> > static int imx8_pcie_phy_init(struct phy *phy)
> >  	reset_control_assert(imx8_phy->reset);
> >
> >  	pad_mode = imx8_phy->refclk_pad_mode;
> > +	switch (imx8_phy->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;
> > +	case IMX8MP:
> > +		reset_control_assert(imx8_phy->perst);
> 
> Could you tell us something more about this reset. What exactly is it resetting.
> Do we really need to assert it before starting the HSIO PLL?
Yes, this reset should be asserted, otherwise, the PCIe wouldn't work.
I'm asking more details of this reset bit from design team, and would update
 later after I get the response.

> AFAICS the PLL should be pretty much independent of the PHY.
Agree.

> 
> Do we need to enable this PLL when the PHY gets an external refclock? I
> couldn't test it yet, but I suspect that the HSIO PLL is only needed as an
> internal reference, when the i.MX8MP is the refclock source, either through
> the PHY pads or via a clkout from the PLL.
> 
Refer to my experience, the HSIO PLL should be enabled firstly.

> > +		/* Set P=12,M=800,S=4 and must set ICP=2'b01. */
> > +		regmap_update_bits(imx8_phy->hsio_blk_ctrl, IMX8MP_GPR_REG2,
> > +				   IMX8MP_GPR_P_PLL_MASK |
> > +				   IMX8MP_GPR_M_PLL_MASK |
> > +				   IMX8MP_GPR_S_PLL_MASK,
> > +				   IMX8MP_GPR_P_PLL |
> > +				   IMX8MP_GPR_M_PLL |
> > +				   IMX8MP_GPR_S_PLL);
> > +		/* wait greater than 1/F_FREF =1/2MHZ=0.5us */
> > +		udelay(1);
> > +
> > +		regmap_update_bits(imx8_phy->hsio_blk_ctrl, IMX8MP_GPR_REG3,
> > +				   IMX8MP_GPR_PLL_RST,
> > +				   IMX8MP_GPR_PLL_RST);
> > +		udelay(10);
> > +
> > +		/* Set 1 to pll_cke of GPR_REG3 */
> > +		regmap_update_bits(imx8_phy->hsio_blk_ctrl, IMX8MP_GPR_REG3,
> > +				   IMX8MP_GPR_PLL_CKE,
> > +				   IMX8MP_GPR_PLL_CKE);
> > +
> > +		/* Lock time should be greater than 300cycle=300*0.5us=150us */
> > +		ret = regmap_read_poll_timeout(imx8_phy->hsio_blk_ctrl,
> > +					     IMX8MP_GPR_REG1, val,
> > +					     val & IMX8MP_GPR_PLL_LOCK,
> > +					     10, 1000);
> > +		if (ret) {
> > +			dev_err(imx8_phy->dev, "PCIe PLL lock timeout\n");
> > +			return ret;
> > +		}
> > +
> > +		/* pcie_clock_module_en */
> > +		regmap_update_bits(imx8_phy->hsio_blk_ctrl, IMX8MP_GPR_REG0,
> > +				   IMX8MP_GPR_CLK_MOD_EN,
> > +				   IMX8MP_GPR_CLK_MOD_EN);
> 
> You shouldn't need to touch this bit. The HSIO blk-ctrl already enables this bit
> when the PCIe power-domain is powered up.
Okay, got that.

> 
> > +		udelay(10);
> > +
> > +		reset_control_deassert(imx8_phy->reset);
> > +		reset_control_deassert(imx8_phy->perst);
> > +
> > +		/* release pcie_phy_apb_reset and pcie_phy_init_resetn */
> > +		regmap_update_bits(imx8_phy->hsio_blk_ctrl, IMX8MP_GPR_REG0,
> > +				   IMX8MP_GPR_PHY_APB_RST |
> > +				   IMX8MP_GPR_PHY_INIT_RST,
> > +				   IMX8MP_GPR_PHY_APB_RST |
> > +				   IMX8MP_GPR_PHY_INIT_RST);
> 
> Not sure about those yet. We might want to toggle them via a virtual PD in the
> HSIO blk-ctrl.
Refer to my understand, these reset should be a part of power-up sequence of
 the PHY. It's reasonable to toggle them via a PD.

> 
> > +		break;
> > +	}
> > +
> > +	if (pad_mode == IMX8_PCIE_REFCLK_PAD_INPUT) {
> > +		/* Configure the pad as input */
> > +		val = readl(imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG061);
> > +		writel(val & ~ANA_PLL_CLK_OUT_TO_EXT_IO_EN,
> > +		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG061);
> > +	} else if (pad_mode == IMX8_PCIE_REFCLK_PAD_OUTPUT) {
> > +		/* Configure the PHY to output the refclock via pad */
> > +		writel(ANA_PLL_CLK_OUT_TO_EXT_IO_EN,
> > +		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG061);
> > +		writel(ANA_PLL_CLK_OUT_TO_EXT_IO_SEL,
> > +		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG062);
> > +		writel(AUX_PLL_REFCLK_SEL_SYS_PLL,
> > +		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG063);
> > +		val = ANA_AUX_RX_TX_SEL_TX | ANA_AUX_TX_TERM;
> > +		writel(val | ANA_AUX_RX_TERM_GND_EN,
> > +		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG064);
> > +		writel(ANA_AUX_RX_TERM | ANA_AUX_TX_LVL,
> > +		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG065);
> > +	}
> > +
> >  	/* 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, @@ -91,42
> +199,30 @@ static
> > int imx8_pcie_phy_init(struct phy *phy)
> >  	regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
> >  			   IMX8MM_GPR_PCIE_CMN_RST,
> >  			   IMX8MM_GPR_PCIE_CMN_RST);
> > -	usleep_range(200, 500);
> >
> > -	if (pad_mode == IMX8_PCIE_REFCLK_PAD_INPUT) {
> > -		/* Configure the pad as input */
> > -		val = readl(imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG061);
> > -		writel(val & ~ANA_PLL_CLK_OUT_TO_EXT_IO_EN,
> > -		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG061);
> > -	} else if (pad_mode == IMX8_PCIE_REFCLK_PAD_OUTPUT) {
> > -		/* Configure the PHY to output the refclock via pad */
> > -		writel(ANA_PLL_CLK_OUT_TO_EXT_IO_EN,
> > -		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG061);
> > -		writel(ANA_PLL_CLK_OUT_TO_EXT_IO_SEL,
> > -		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG062);
> > -		writel(AUX_PLL_REFCLK_SEL_SYS_PLL,
> > -		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG063);
> > -		val = ANA_AUX_RX_TX_SEL_TX | ANA_AUX_TX_TERM;
> > -		writel(val | ANA_AUX_RX_TERM_GND_EN,
> > -		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG064);
> > -		writel(ANA_AUX_RX_TERM | ANA_AUX_TX_LVL,
> > -		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG065);
> > +	switch (imx8_phy->variant) {
> > +	case IMX8MM:
> > +		reset_control_deassert(imx8_phy->reset);
> > +		usleep_range(200, 500);
> > +		break;
> > +
> > +	case IMX8MP:
> > +		/* wait for core_clk enabled */
> > +		ret = regmap_read_poll_timeout(imx8_phy->hsio_blk_ctrl,
> > +					     IMX8MP_GPR_REG1, val,
> > +					     val & IMX8MP_GPR_PM_EN_CORE_CLK,
> > +					     10, 20000);
> > +		if (ret) {
> > +			dev_err(imx8_phy->dev, "PCIe CORE CLK enable failed\n");
> > +			return ret;
> > +		}
> > +
> > +		break;
> >  	}
> >
> > -	/* 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);
> > -
> > -	reset_control_deassert(imx8_phy->reset);
> > -
> >  	/* Polling to check the phy is ready or not. */
> > -	ret = readl_poll_timeout(imx8_phy->base +
> IMX8MM_PCIE_PHY_CMN_REG75,
> > -				 val, val == PCIE_PHY_CMN_REG75_PLL_DONE,
> > -				 10, 20000);
> > +	ret = readl_poll_timeout(imx8_phy->base +
> IMX8MM_PCIE_PHY_CMN_REG075,
> > +				 val, val == ANA_PLL_DONE, 10, 20000);
> >  	return ret;
> >  }
> >
> > @@ -153,18 +249,33 @@ static const struct phy_ops imx8_pcie_phy_ops =
> {
> >  	.owner		= THIS_MODULE,
> >  };
> >
> > +static const struct of_device_id imx8_pcie_phy_of_match[] = {
> > +	{.compatible = "fsl,imx8mm-pcie-phy", .data = (void *)IMX8MM},
> > +	{.compatible = "fsl,imx8mp-pcie-phy", .data = (void *)IMX8MP},
> > +	{ },
> > +};
> > +MODULE_DEVICE_TABLE(of, imx8_pcie_phy_of_match);
> > +
> >  static int imx8_pcie_phy_probe(struct platform_device *pdev)  {
> >  	struct phy_provider *phy_provider;
> >  	struct device *dev = &pdev->dev;
> > +	const struct of_device_id *of_id;
> >  	struct device_node *np = dev->of_node;
> >  	struct imx8_pcie_phy *imx8_phy;
> >  	struct resource *res;
> >
> > +	of_id = of_match_device(imx8_pcie_phy_of_match, dev);
> > +	if (!of_id)
> > +		return -EINVAL;
> > +
> >  	imx8_phy = devm_kzalloc(dev, sizeof(*imx8_phy), GFP_KERNEL);
> >  	if (!imx8_phy)
> >  		return -ENOMEM;
> >
> > +	imx8_phy->dev = dev;
> > +	imx8_phy->variant = (enum imx8_pcie_phy_type)of_id->data;
> > +
> >  	/* get PHY refclk pad mode */
> >  	of_property_read_u32(np, "fsl,refclk-pad-mode",
> >  			     &imx8_phy->refclk_pad_mode);
> > @@ -201,6 +312,22 @@ static int imx8_pcie_phy_probe(struct
> platform_device *pdev)
> >  		dev_err(dev, "Failed to get PCIEPHY reset control\n");
> >  		return PTR_ERR(imx8_phy->reset);
> >  	}
> > +	if (imx8_phy->variant == IMX8MP) {
> > +		/* Grab HSIO MIX config register range */
> > +		imx8_phy->hsio_blk_ctrl =
> > +
> syscon_regmap_lookup_by_compatible("fsl,imx8mp-hsio-blk-ctrl");
> > +		if (IS_ERR(imx8_phy->hsio_blk_ctrl)) {
> > +			dev_err(dev, "unable to find hsio mix registers\n");
> > +			return PTR_ERR(imx8_phy->hsio_blk_ctrl);
> > +		}
> > +
> > +		imx8_phy->perst =
> > +			devm_reset_control_get_exclusive(dev, "perst");
> > +		if (IS_ERR(imx8_phy->perst)) {
> > +			dev_err(dev, "Failed to get PCIEPHY perst control\n");
> > +			return PTR_ERR(imx8_phy->perst);
> > +		}
> > +	}
> 
> I still hope that we can push all the HSIO blk-ctrl register access into the
> blk-ctrl driver, by adding the PLL as a clock there and maybe abstracting the
> PHY reset bits a virtual PD for the PHY, so we don't need this direct access in
> the PHY driver. Depends a bit on weather we are able to get the sequencing
> right when splitting things across multiple drivers.

Agree, thanks for your considerations.

Best Regards
Richard Zhu
> 
> Regards,
> Lucas
> 
> >
> >  	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> >  	imx8_phy->base = devm_ioremap_resource(dev, res); @@ -218,12 +345,6
> > @@ 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 = {
>

Lucas Stach April 27, 2022, 3:18 p.m. UTC | #5

Hi Richard,

Am Montag, dem 18.04.2022 um 04:55 +0000 schrieb Hongxing Zhu:
> > -----Original Message-----
> > From: Lucas Stach <[e-mail]>
> > Sent: 2022年4月15日 4:59
> > To: Hongxing Zhu <[e-mail]>; [e-mail];
> > [e-mail]; [e-mail]; [e-mail];
> > [e-mail]; [e-mail]; [e-mail]
> > Cc: [e-mail]; [e-mail];
> > [e-mail]; [e-mail];
> > [e-mail]; [e-mail]; dl-linux-imx
> > <[e-mail]>
> > Subject: Re: [PATCH v2 3/7] phy: freescale: imx8m-pcie: Add iMX8MP PCIe PHY
> > support
> > 
> > Am Montag, dem 07.03.2022 um 17:07 +0800 schrieb Richard Zhu:
> > > Add the i.MX8MP PCIe PHY support
> > > 
> > > Signed-off-by: Richard Zhu <[e-mail]>
> > > ---
> > >  drivers/phy/freescale/phy-fsl-imx8m-pcie.c | 205
> > > ++++++++++++++++-----
> > >  1 file changed, 163 insertions(+), 42 deletions(-)
> > > 
> > > diff --git a/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
> > > b/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
> > > index 04b1aafb29f4..3d01da4323a6 100644
> > > --- a/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
> > > +++ b/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
> > > @@ -11,6 +11,8 @@
> > >  #include <linux/mfd/syscon.h>
> > >  #include <linux/mfd/syscon/imx7-iomuxc-gpr.h>
> > >  #include <linux/module.h>
> > > +#include <linux/of_address.h>
> > > +#include <linux/of_device.h>
> > >  #include <linux/phy/phy.h>
> > >  #include <linux/platform_device.h>
> > >  #include <linux/regmap.h>
> > > @@ -30,12 +32,10 @@
> > >  #define IMX8MM_PCIE_PHY_CMN_REG065	0x194
> > >  #define  ANA_AUX_RX_TERM		(BIT(7) | BIT(4))
> > >  #define  ANA_AUX_TX_LVL			GENMASK(3, 0)
> > > -#define IMX8MM_PCIE_PHY_CMN_REG75	0x1D4
> > > -#define  PCIE_PHY_CMN_REG75_PLL_DONE	0x3
> > > +#define IMX8MM_PCIE_PHY_CMN_REG075	0x1D4
> > > +#define  ANA_PLL_DONE			0x3
> > 
> > Why do you drop the register prefix from the name here?
> To prevent the codes from exceeding the 80 columns and align with the other
>  bit definitions, drop the prefix and keep the bit definitions as short as
>  possible.
> 
> > 
> > >  #define PCIE_PHY_TRSV_REG5		0x414
> > > -#define  PCIE_PHY_TRSV_REG5_GEN1_DEEMP	0x2D
> > >  #define PCIE_PHY_TRSV_REG6		0x418
> > > -#define  PCIE_PHY_TRSV_REG6_GEN2_DEEMP	0xF
> > > 
> > >  #define IMX8MM_GPR_PCIE_REF_CLK_SEL	GENMASK(25, 24)
> > >  #define IMX8MM_GPR_PCIE_REF_CLK_PLL
> > 	FIELD_PREP(IMX8MM_GPR_PCIE_REF_CLK_SEL, 0x3)
> > > @@ -46,16 +46,43 @@
> > >  #define IMX8MM_GPR_PCIE_SSC_EN		BIT(16)
> > >  #define IMX8MM_GPR_PCIE_AUX_EN_OVERRIDE	BIT(9)
> > > 
> > > +#define IMX8MP_GPR_REG0			0x0
> > > +#define IMX8MP_GPR_CLK_MOD_EN		BIT(0)
> > > +#define IMX8MP_GPR_PHY_APB_RST		BIT(4)
> > > +#define IMX8MP_GPR_PHY_INIT_RST		BIT(5)
> > > +#define IMX8MP_GPR_REG1			0x4
> > > +#define IMX8MP_GPR_PM_EN_CORE_CLK	BIT(0)
> > > +#define IMX8MP_GPR_PLL_LOCK		BIT(13)
> > > +#define IMX8MP_GPR_REG2			0x8
> > > +#define IMX8MP_GPR_P_PLL_MASK		GENMASK(5, 0)
> > > +#define IMX8MP_GPR_M_PLL_MASK		GENMASK(15, 6)
> > > +#define IMX8MP_GPR_S_PLL_MASK		GENMASK(18, 16)
> > > +#define IMX8MP_GPR_P_PLL		(0xc << 0)
> > > +#define IMX8MP_GPR_M_PLL		(0x320 << 6)
> > > +#define IMX8MP_GPR_S_PLL		(0x4 << 16)
> > > +#define IMX8MP_GPR_REG3			0xc
> > > +#define IMX8MP_GPR_PLL_CKE		BIT(17)
> > > +#define IMX8MP_GPR_PLL_RST		BIT(31)
> > > +
> > > +enum imx8_pcie_phy_type {
> > > +	IMX8MM,
> > > +	IMX8MP,
> > > +};
> > > +
> > >  struct imx8_pcie_phy {
> > >  	void __iomem		*base;
> > > +	struct device		*dev;
> > >  	struct clk		*clk;
> > >  	struct phy		*phy;
> > > +	struct regmap		*hsio_blk_ctrl;
> > >  	struct regmap		*iomuxc_gpr;
> > >  	struct reset_control	*reset;
> > > +	struct reset_control	*perst;
> > >  	u32			refclk_pad_mode;
> > >  	u32			tx_deemph_gen1;
> > >  	u32			tx_deemph_gen2;
> > >  	bool			clkreq_unused;
> > > +	enum imx8_pcie_phy_type	variant;
> > >  };
> > > 
> > >  static int imx8_pcie_phy_init(struct phy *phy) @@ -67,6 +94,87 @@
> > > static int imx8_pcie_phy_init(struct phy *phy)
> > >  	reset_control_assert(imx8_phy->reset);
> > > 
> > >  	pad_mode = imx8_phy->refclk_pad_mode;
> > > +	switch (imx8_phy->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;
> > > +	case IMX8MP:
> > > +		reset_control_assert(imx8_phy->perst);
> > 
> > Could you tell us something more about this reset. What exactly is it resetting.
> > Do we really need to assert it before starting the HSIO PLL?
> Yes, this reset should be asserted, otherwise, the PCIe wouldn't work.
> I'm asking more details of this reset bit from design team, and would update
>  later after I get the response.
> 
> > AFAICS the PLL should be pretty much independent of the PHY.
> Agree.
> 
> > 
> > Do we need to enable this PLL when the PHY gets an external refclock? I
> > couldn't test it yet, but I suspect that the HSIO PLL is only needed as an
> > internal reference, when the i.MX8MP is the refclock source, either through
> > the PHY pads or via a clkout from the PLL.
> > 
> Refer to my experience, the HSIO PLL should be enabled firstly.
> 
> > > +		/* Set P=12,M=800,S=4 and must set ICP=2'b01. */
> > > +		regmap_update_bits(imx8_phy->hsio_blk_ctrl, IMX8MP_GPR_REG2,
> > > +				   IMX8MP_GPR_P_PLL_MASK |
> > > +				   IMX8MP_GPR_M_PLL_MASK |
> > > +				   IMX8MP_GPR_S_PLL_MASK,
> > > +				   IMX8MP_GPR_P_PLL |
> > > +				   IMX8MP_GPR_M_PLL |
> > > +				   IMX8MP_GPR_S_PLL);
> > > +		/* wait greater than 1/F_FREF =1/2MHZ=0.5us */
> > > +		udelay(1);
> > > +
> > > +		regmap_update_bits(imx8_phy->hsio_blk_ctrl, IMX8MP_GPR_REG3,
> > > +				   IMX8MP_GPR_PLL_RST,
> > > +				   IMX8MP_GPR_PLL_RST);
> > > +		udelay(10);
> > > +
> > > +		/* Set 1 to pll_cke of GPR_REG3 */
> > > +		regmap_update_bits(imx8_phy->hsio_blk_ctrl, IMX8MP_GPR_REG3,
> > > +				   IMX8MP_GPR_PLL_CKE,
> > > +				   IMX8MP_GPR_PLL_CKE);
> > > +
> > > +		/* Lock time should be greater than 300cycle=300*0.5us=150us */
> > > +		ret = regmap_read_poll_timeout(imx8_phy->hsio_blk_ctrl,
> > > +					     IMX8MP_GPR_REG1, val,
> > > +					     val & IMX8MP_GPR_PLL_LOCK,
> > > +					     10, 1000);
> > > +		if (ret) {
> > > +			dev_err(imx8_phy->dev, "PCIe PLL lock timeout\n");
> > > +			return ret;
> > > +		}
> > > +
> > > +		/* pcie_clock_module_en */
> > > +		regmap_update_bits(imx8_phy->hsio_blk_ctrl, IMX8MP_GPR_REG0,
> > > +				   IMX8MP_GPR_CLK_MOD_EN,
> > > +				   IMX8MP_GPR_CLK_MOD_EN);
> > 
> > You shouldn't need to touch this bit. The HSIO blk-ctrl already enables this bit
> > when the PCIe power-domain is powered up.
> Okay, got that.
> 
> > 
> > > +		udelay(10);
> > > +
> > > +		reset_control_deassert(imx8_phy->reset);
> > > +		reset_control_deassert(imx8_phy->perst);
> > > +
> > > +		/* release pcie_phy_apb_reset and pcie_phy_init_resetn */
> > > +		regmap_update_bits(imx8_phy->hsio_blk_ctrl, IMX8MP_GPR_REG0,
> > > +				   IMX8MP_GPR_PHY_APB_RST |
> > > +				   IMX8MP_GPR_PHY_INIT_RST,
> > > +				   IMX8MP_GPR_PHY_APB_RST |
> > > +				   IMX8MP_GPR_PHY_INIT_RST);
> > 
> > Not sure about those yet. We might want to toggle them via a virtual PD in the
> > HSIO blk-ctrl.
> Refer to my understand, these reset should be a part of power-up sequence of
>  the PHY. It's reasonable to toggle them via a PD.

So I had a chance to look into why this series isn't working for me
some more.

It seems the full PHY initialization fails, as the complete PHY MMIO
region reads back as 0xff. This hints at either a missing clock, or
(more likely) the register interface of the PHY being held in reset.
Note that I'm running upstream TF-A and the Barebox bootloader, so this
might be a missing initialization somewhere, that is done by downstream
TF-A or U-Boot.

Sadly the above bits are also not documented in the RM, but are marked
as reserved. By chance, do you know about any other secondary
clocks/resets that may have an impact on PCIe?

Regards,
Lucas

Hongxing Zhu April 28, 2022, 1:29 a.m. UTC | #6

> -----Original Message-----
> From: Lucas Stach <[e-mail]>
> Sent: 2022年4月27日 23:19
> To: Hongxing Zhu <[e-mail]>; [e-mail];
> [e-mail]; [e-mail]; [e-mail];
> [e-mail]; [e-mail]; [e-mail]
> Cc: [e-mail]; [e-mail];
> [e-mail]; [e-mail];
> [e-mail]; [e-mail]; dl-linux-imx
> <[e-mail]>
> Subject: Re: [PATCH v2 3/7] phy: freescale: imx8m-pcie: Add iMX8MP PCIe PHY
> support
> 
> Hi Richard,
> 
> Am Montag, dem 18.04.2022 um 04:55 +0000 schrieb Hongxing Zhu:
> > > -----Original Message-----
> > > From: Lucas Stach <[e-mail]>
> > > Sent: 2022年4月15日 4:59
> > > To: Hongxing Zhu <[e-mail]>; [e-mail];
> > > [e-mail]; [e-mail]; [e-mail];
> > > [e-mail]; [e-mail];
> > > [e-mail]
> > > Cc: [e-mail]; [e-mail];
> > > [e-mail]; [e-mail];
> > > [e-mail]; [e-mail]; dl-linux-imx
> > > <[e-mail]>
> > > Subject: Re: [PATCH v2 3/7] phy: freescale: imx8m-pcie: Add iMX8MP
> > > PCIe PHY support
> > >
> > > Am Montag, dem 07.03.2022 um 17:07 +0800 schrieb Richard Zhu:
> > > > Add the i.MX8MP PCIe PHY support
> > > >
> > > > Signed-off-by: Richard Zhu <[e-mail]>
> > > > ---
> > > >  drivers/phy/freescale/phy-fsl-imx8m-pcie.c | 205
> > > > ++++++++++++++++-----
> > > >  1 file changed, 163 insertions(+), 42 deletions(-)
> > > >
> > > > diff --git a/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
> > > > b/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
> > > > index 04b1aafb29f4..3d01da4323a6 100644
> > > > --- a/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
> > > > +++ b/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
> > > > @@ -11,6 +11,8 @@
> > > >  #include <linux/mfd/syscon.h>
> > > >  #include <linux/mfd/syscon/imx7-iomuxc-gpr.h>
> > > >  #include <linux/module.h>
> > > > +#include <linux/of_address.h>
> > > > +#include <linux/of_device.h>
> > > >  #include <linux/phy/phy.h>
> > > >  #include <linux/platform_device.h>
> > > >  #include <linux/regmap.h>
> > > > @@ -30,12 +32,10 @@
> > > >  #define IMX8MM_PCIE_PHY_CMN_REG065	0x194
> > > >  #define  ANA_AUX_RX_TERM		(BIT(7) | BIT(4))
> > > >  #define  ANA_AUX_TX_LVL			GENMASK(3, 0)
> > > > -#define IMX8MM_PCIE_PHY_CMN_REG75	0x1D4
> > > > -#define  PCIE_PHY_CMN_REG75_PLL_DONE	0x3
> > > > +#define IMX8MM_PCIE_PHY_CMN_REG075	0x1D4
> > > > +#define  ANA_PLL_DONE			0x3
> > >
> > > Why do you drop the register prefix from the name here?
> > To prevent the codes from exceeding the 80 columns and align with the
> > other
> >  bit definitions, drop the prefix and keep the bit definitions as
> > short as
> >  possible.
> >
> > >
> > > >  #define PCIE_PHY_TRSV_REG5		0x414
> > > > -#define  PCIE_PHY_TRSV_REG5_GEN1_DEEMP	0x2D
> > > >  #define PCIE_PHY_TRSV_REG6		0x418
> > > > -#define  PCIE_PHY_TRSV_REG6_GEN2_DEEMP	0xF
> > > >
> > > >  #define IMX8MM_GPR_PCIE_REF_CLK_SEL	GENMASK(25, 24)
> > > >  #define IMX8MM_GPR_PCIE_REF_CLK_PLL
> > > 	FIELD_PREP(IMX8MM_GPR_PCIE_REF_CLK_SEL, 0x3)
> > > > @@ -46,16 +46,43 @@
> > > >  #define IMX8MM_GPR_PCIE_SSC_EN		BIT(16)
> > > >  #define IMX8MM_GPR_PCIE_AUX_EN_OVERRIDE	BIT(9)
> > > >
> > > > +#define IMX8MP_GPR_REG0			0x0
> > > > +#define IMX8MP_GPR_CLK_MOD_EN		BIT(0)
> > > > +#define IMX8MP_GPR_PHY_APB_RST		BIT(4)
> > > > +#define IMX8MP_GPR_PHY_INIT_RST		BIT(5)
> > > > +#define IMX8MP_GPR_REG1			0x4
> > > > +#define IMX8MP_GPR_PM_EN_CORE_CLK	BIT(0)
> > > > +#define IMX8MP_GPR_PLL_LOCK		BIT(13)
> > > > +#define IMX8MP_GPR_REG2			0x8
> > > > +#define IMX8MP_GPR_P_PLL_MASK		GENMASK(5, 0)
> > > > +#define IMX8MP_GPR_M_PLL_MASK		GENMASK(15, 6)
> > > > +#define IMX8MP_GPR_S_PLL_MASK		GENMASK(18, 16)
> > > > +#define IMX8MP_GPR_P_PLL		(0xc << 0)
> > > > +#define IMX8MP_GPR_M_PLL		(0x320 << 6)
> > > > +#define IMX8MP_GPR_S_PLL		(0x4 << 16)
> > > > +#define IMX8MP_GPR_REG3			0xc
> > > > +#define IMX8MP_GPR_PLL_CKE		BIT(17)
> > > > +#define IMX8MP_GPR_PLL_RST		BIT(31)
> > > > +
> > > > +enum imx8_pcie_phy_type {
> > > > +	IMX8MM,
> > > > +	IMX8MP,
> > > > +};
> > > > +
> > > >  struct imx8_pcie_phy {
> > > >  	void __iomem		*base;
> > > > +	struct device		*dev;
> > > >  	struct clk		*clk;
> > > >  	struct phy		*phy;
> > > > +	struct regmap		*hsio_blk_ctrl;
> > > >  	struct regmap		*iomuxc_gpr;
> > > >  	struct reset_control	*reset;
> > > > +	struct reset_control	*perst;
> > > >  	u32			refclk_pad_mode;
> > > >  	u32			tx_deemph_gen1;
> > > >  	u32			tx_deemph_gen2;
> > > >  	bool			clkreq_unused;
> > > > +	enum imx8_pcie_phy_type	variant;
> > > >  };
> > > >
> > > >  static int imx8_pcie_phy_init(struct phy *phy) @@ -67,6 +94,87 @@
> > > > static int imx8_pcie_phy_init(struct phy *phy)
> > > >  	reset_control_assert(imx8_phy->reset);
> > > >
> > > >  	pad_mode = imx8_phy->refclk_pad_mode;
> > > > +	switch (imx8_phy->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;
> > > > +	case IMX8MP:
> > > > +		reset_control_assert(imx8_phy->perst);
> > >
> > > Could you tell us something more about this reset. What exactly is it
> resetting.
> > > Do we really need to assert it before starting the HSIO PLL?
> > Yes, this reset should be asserted, otherwise, the PCIe wouldn't work.
> > I'm asking more details of this reset bit from design team, and would
> > update
> >  later after I get the response.
> >
> > > AFAICS the PLL should be pretty much independent of the PHY.
> > Agree.
> >
> > >
> > > Do we need to enable this PLL when the PHY gets an external
> > > refclock? I couldn't test it yet, but I suspect that the HSIO PLL is
> > > only needed as an internal reference, when the i.MX8MP is the
> > > refclock source, either through the PHY pads or via a clkout from the PLL.
> > >
> > Refer to my experience, the HSIO PLL should be enabled firstly.
> >
> > > > +		/* Set P=12,M=800,S=4 and must set ICP=2'b01. */
> > > > +		regmap_update_bits(imx8_phy->hsio_blk_ctrl,
> IMX8MP_GPR_REG2,
> > > > +				   IMX8MP_GPR_P_PLL_MASK |
> > > > +				   IMX8MP_GPR_M_PLL_MASK |
> > > > +				   IMX8MP_GPR_S_PLL_MASK,
> > > > +				   IMX8MP_GPR_P_PLL |
> > > > +				   IMX8MP_GPR_M_PLL |
> > > > +				   IMX8MP_GPR_S_PLL);
> > > > +		/* wait greater than 1/F_FREF =1/2MHZ=0.5us */
> > > > +		udelay(1);
> > > > +
> > > > +		regmap_update_bits(imx8_phy->hsio_blk_ctrl,
> IMX8MP_GPR_REG3,
> > > > +				   IMX8MP_GPR_PLL_RST,
> > > > +				   IMX8MP_GPR_PLL_RST);
> > > > +		udelay(10);
> > > > +
> > > > +		/* Set 1 to pll_cke of GPR_REG3 */
> > > > +		regmap_update_bits(imx8_phy->hsio_blk_ctrl,
> IMX8MP_GPR_REG3,
> > > > +				   IMX8MP_GPR_PLL_CKE,
> > > > +				   IMX8MP_GPR_PLL_CKE);
> > > > +
> > > > +		/* Lock time should be greater than 300cycle=300*0.5us=150us
> */
> > > > +		ret = regmap_read_poll_timeout(imx8_phy->hsio_blk_ctrl,
> > > > +					     IMX8MP_GPR_REG1, val,
> > > > +					     val & IMX8MP_GPR_PLL_LOCK,
> > > > +					     10, 1000);
> > > > +		if (ret) {
> > > > +			dev_err(imx8_phy->dev, "PCIe PLL lock timeout\n");
> > > > +			return ret;
> > > > +		}
> > > > +
> > > > +		/* pcie_clock_module_en */
> > > > +		regmap_update_bits(imx8_phy->hsio_blk_ctrl,
> IMX8MP_GPR_REG0,
> > > > +				   IMX8MP_GPR_CLK_MOD_EN,
> > > > +				   IMX8MP_GPR_CLK_MOD_EN);
> > >
> > > You shouldn't need to touch this bit. The HSIO blk-ctrl already
> > > enables this bit when the PCIe power-domain is powered up.
> > Okay, got that.
> >
> > >
> > > > +		udelay(10);
> > > > +
> > > > +		reset_control_deassert(imx8_phy->reset);
> > > > +		reset_control_deassert(imx8_phy->perst);
> > > > +
> > > > +		/* release pcie_phy_apb_reset and pcie_phy_init_resetn */
> > > > +		regmap_update_bits(imx8_phy->hsio_blk_ctrl,
> IMX8MP_GPR_REG0,
> > > > +				   IMX8MP_GPR_PHY_APB_RST |
> > > > +				   IMX8MP_GPR_PHY_INIT_RST,
> > > > +				   IMX8MP_GPR_PHY_APB_RST |
> > > > +				   IMX8MP_GPR_PHY_INIT_RST);
> > >
> > > Not sure about those yet. We might want to toggle them via a virtual
> > > PD in the HSIO blk-ctrl.
> > Refer to my understand, these reset should be a part of power-up
> > sequence of
> >  the PHY. It's reasonable to toggle them via a PD.
> 
> So I had a chance to look into why this series isn't working for me some more.
> 
> It seems the full PHY initialization fails, as the complete PHY MMIO region
> reads back as 0xff. This hints at either a missing clock, or (more likely) the
> register interface of the PHY being held in reset.
> Note that I'm running upstream TF-A and the Barebox bootloader, so this
> might be a missing initialization somewhere, that is done by downstream TF-A
> or U-Boot.
> 
> Sadly the above bits are also not documented in the RM, but are marked as
> reserved. By chance, do you know about any other secondary clocks/resets
> that may have an impact on PCIe?
> 
Hi Lucas:
Thanks for your help to look at this series.
Refer to your descriptions, it seems that one initial version i.MX865 chip
 is used at your side.
There is a design bug in the initial version of i.MX865 PCIe. All the PHY MMIO
 region reads back as 0xff.
It is fixed by the later chips. Find another newer board is a quick method to
 fix it. Or, apply one SW workaround to let it work only in Gen1/Gen2 modes.

Best Regards
Richard Zhu

> Regards,
> Lucas

Hongxing Zhu May 26, 2022, 1:32 a.m. UTC | #7

Hi Lucas:

> -----Original Message-----
> From: Hongxing Zhu
> Sent: 2022年4月28日 9:30
> To: Lucas Stach <[e-mail]>; [e-mail];
> [e-mail]; [e-mail]; [e-mail];
> [e-mail]; [e-mail]; [e-mail]
> Cc: [e-mail]; [e-mail];
> [e-mail]; [e-mail];
> [e-mail]; [e-mail]; dl-linux-imx
> <[e-mail]>
> Subject: RE: [PATCH v2 3/7] phy: freescale: imx8m-pcie: Add iMX8MP PCIe PHY
> support
> 
> > -----Original Message-----
> > From: Lucas Stach <[e-mail]>
> > Sent: 2022年4月27日 23:19
> > To: Hongxing Zhu <[e-mail]>; [e-mail];
> > [e-mail]; [e-mail]; [e-mail];
> > [e-mail]; [e-mail]; [e-mail]
> > Cc: [e-mail]; [e-mail];
> > [e-mail]; [e-mail];
> > [e-mail]; [e-mail]; dl-linux-imx
> > <[e-mail]>
> > Subject: Re: [PATCH v2 3/7] phy: freescale: imx8m-pcie: Add iMX8MP
> > PCIe PHY support
> >
> > Hi Richard,
> >
> > Am Montag, dem 18.04.2022 um 04:55 +0000 schrieb Hongxing Zhu:
> > > > -----Original Message-----
> > > > From: Lucas Stach <[e-mail]>
> > > > Sent: 2022年4月15日 4:59
> > > > To: Hongxing Zhu <[e-mail]>; [e-mail];
> > > > [e-mail]; [e-mail]; [e-mail];
> > > > [e-mail]; [e-mail];
> > > > [e-mail]
> > > > Cc: [e-mail]; [e-mail];
> > > > [e-mail]; [e-mail];
> > > > [e-mail]; [e-mail]; dl-linux-imx
> > > > <[e-mail]>
> > > > Subject: Re: [PATCH v2 3/7] phy: freescale: imx8m-pcie: Add iMX8MP
> > > > PCIe PHY support
> > > >
> > > > Am Montag, dem 07.03.2022 um 17:07 +0800 schrieb Richard Zhu:
> > > > > Add the i.MX8MP PCIe PHY support
> > > > >
> > > > > Signed-off-by: Richard Zhu <[e-mail]>
> > > > > ---
> > > > >  drivers/phy/freescale/phy-fsl-imx8m-pcie.c | 205
> > > > > ++++++++++++++++-----
> > > > >  1 file changed, 163 insertions(+), 42 deletions(-)
> > > > >
> > > > > diff --git a/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
> > > > > b/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
> > > > > index 04b1aafb29f4..3d01da4323a6 100644
> > > > > --- a/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
> > > > > +++ b/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
> > > > > @@ -11,6 +11,8 @@
> > > > >  #include <linux/mfd/syscon.h>
> > > > >  #include <linux/mfd/syscon/imx7-iomuxc-gpr.h>
> > > > >  #include <linux/module.h>
> > > > > +#include <linux/of_address.h>
> > > > > +#include <linux/of_device.h>
> > > > >  #include <linux/phy/phy.h>
> > > > >  #include <linux/platform_device.h>
> > > > >  #include <linux/regmap.h>
> > > > > @@ -30,12 +32,10 @@
> > > > >  #define IMX8MM_PCIE_PHY_CMN_REG065	0x194
> > > > >  #define  ANA_AUX_RX_TERM		(BIT(7) | BIT(4))
> > > > >  #define  ANA_AUX_TX_LVL			GENMASK(3, 0)
> > > > > -#define IMX8MM_PCIE_PHY_CMN_REG75	0x1D4
> > > > > -#define  PCIE_PHY_CMN_REG75_PLL_DONE	0x3
> > > > > +#define IMX8MM_PCIE_PHY_CMN_REG075	0x1D4
> > > > > +#define  ANA_PLL_DONE			0x3
> > > >
> > > > Why do you drop the register prefix from the name here?
> > > To prevent the codes from exceeding the 80 columns and align with
> > > the other
> > >  bit definitions, drop the prefix and keep the bit definitions as
> > > short as
> > >  possible.
> > >
> > > >
> > > > >  #define PCIE_PHY_TRSV_REG5		0x414
> > > > > -#define  PCIE_PHY_TRSV_REG5_GEN1_DEEMP	0x2D
> > > > >  #define PCIE_PHY_TRSV_REG6		0x418
> > > > > -#define  PCIE_PHY_TRSV_REG6_GEN2_DEEMP	0xF
> > > > >
> > > > >  #define IMX8MM_GPR_PCIE_REF_CLK_SEL	GENMASK(25, 24)
> > > > >  #define IMX8MM_GPR_PCIE_REF_CLK_PLL
> > > > 	FIELD_PREP(IMX8MM_GPR_PCIE_REF_CLK_SEL, 0x3)
> > > > > @@ -46,16 +46,43 @@
> > > > >  #define IMX8MM_GPR_PCIE_SSC_EN		BIT(16)
> > > > >  #define IMX8MM_GPR_PCIE_AUX_EN_OVERRIDE	BIT(9)
> > > > >
> > > > > +#define IMX8MP_GPR_REG0			0x0
> > > > > +#define IMX8MP_GPR_CLK_MOD_EN		BIT(0)
> > > > > +#define IMX8MP_GPR_PHY_APB_RST		BIT(4)
> > > > > +#define IMX8MP_GPR_PHY_INIT_RST		BIT(5)
> > > > > +#define IMX8MP_GPR_REG1			0x4
> > > > > +#define IMX8MP_GPR_PM_EN_CORE_CLK	BIT(0)
> > > > > +#define IMX8MP_GPR_PLL_LOCK		BIT(13)
> > > > > +#define IMX8MP_GPR_REG2			0x8
> > > > > +#define IMX8MP_GPR_P_PLL_MASK		GENMASK(5, 0)
> > > > > +#define IMX8MP_GPR_M_PLL_MASK		GENMASK(15, 6)
> > > > > +#define IMX8MP_GPR_S_PLL_MASK		GENMASK(18, 16)
> > > > > +#define IMX8MP_GPR_P_PLL		(0xc << 0)
> > > > > +#define IMX8MP_GPR_M_PLL		(0x320 << 6)
> > > > > +#define IMX8MP_GPR_S_PLL		(0x4 << 16)
> > > > > +#define IMX8MP_GPR_REG3			0xc
> > > > > +#define IMX8MP_GPR_PLL_CKE		BIT(17)
> > > > > +#define IMX8MP_GPR_PLL_RST		BIT(31)
> > > > > +
> > > > > +enum imx8_pcie_phy_type {
> > > > > +	IMX8MM,
> > > > > +	IMX8MP,
> > > > > +};
> > > > > +
> > > > >  struct imx8_pcie_phy {
> > > > >  	void __iomem		*base;
> > > > > +	struct device		*dev;
> > > > >  	struct clk		*clk;
> > > > >  	struct phy		*phy;
> > > > > +	struct regmap		*hsio_blk_ctrl;
> > > > >  	struct regmap		*iomuxc_gpr;
> > > > >  	struct reset_control	*reset;
> > > > > +	struct reset_control	*perst;
> > > > >  	u32			refclk_pad_mode;
> > > > >  	u32			tx_deemph_gen1;
> > > > >  	u32			tx_deemph_gen2;
> > > > >  	bool			clkreq_unused;
> > > > > +	enum imx8_pcie_phy_type	variant;
> > > > >  };
> > > > >
> > > > >  static int imx8_pcie_phy_init(struct phy *phy) @@ -67,6 +94,87
> > > > > @@ static int imx8_pcie_phy_init(struct phy *phy)
> > > > >  	reset_control_assert(imx8_phy->reset);
> > > > >
> > > > >  	pad_mode = imx8_phy->refclk_pad_mode;
> > > > > +	switch (imx8_phy->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;
> > > > > +	case IMX8MP:
> > > > > +		reset_control_assert(imx8_phy->perst);
> > > >
> > > > Could you tell us something more about this reset. What exactly is
> > > > it
> > resetting.
> > > > Do we really need to assert it before starting the HSIO PLL?
> > > Yes, this reset should be asserted, otherwise, the PCIe wouldn't work.
> > > I'm asking more details of this reset bit from design team, and
> > > would update
> > >  later after I get the response.
> > >
> > > > AFAICS the PLL should be pretty much independent of the PHY.
> > > Agree.
> > >
> > > >
> > > > Do we need to enable this PLL when the PHY gets an external
> > > > refclock? I couldn't test it yet, but I suspect that the HSIO PLL
> > > > is only needed as an internal reference, when the i.MX8MP is the
> > > > refclock source, either through the PHY pads or via a clkout from the PLL.
> > > >
> > > Refer to my experience, the HSIO PLL should be enabled firstly.
> > >
> > > > > +		/* Set P=12,M=800,S=4 and must set ICP=2'b01. */
> > > > > +		regmap_update_bits(imx8_phy->hsio_blk_ctrl,
> > IMX8MP_GPR_REG2,
> > > > > +				   IMX8MP_GPR_P_PLL_MASK |
> > > > > +				   IMX8MP_GPR_M_PLL_MASK |
> > > > > +				   IMX8MP_GPR_S_PLL_MASK,
> > > > > +				   IMX8MP_GPR_P_PLL |
> > > > > +				   IMX8MP_GPR_M_PLL |
> > > > > +				   IMX8MP_GPR_S_PLL);
> > > > > +		/* wait greater than 1/F_FREF =1/2MHZ=0.5us */
> > > > > +		udelay(1);
> > > > > +
> > > > > +		regmap_update_bits(imx8_phy->hsio_blk_ctrl,
> > IMX8MP_GPR_REG3,
> > > > > +				   IMX8MP_GPR_PLL_RST,
> > > > > +				   IMX8MP_GPR_PLL_RST);
> > > > > +		udelay(10);
> > > > > +
> > > > > +		/* Set 1 to pll_cke of GPR_REG3 */
> > > > > +		regmap_update_bits(imx8_phy->hsio_blk_ctrl,
> > IMX8MP_GPR_REG3,
> > > > > +				   IMX8MP_GPR_PLL_CKE,
> > > > > +				   IMX8MP_GPR_PLL_CKE);
> > > > > +
> > > > > +		/* Lock time should be greater than 300cycle=300*0.5us=150us
> > */
> > > > > +		ret = regmap_read_poll_timeout(imx8_phy->hsio_blk_ctrl,
> > > > > +					     IMX8MP_GPR_REG1, val,
> > > > > +					     val & IMX8MP_GPR_PLL_LOCK,
> > > > > +					     10, 1000);
> > > > > +		if (ret) {
> > > > > +			dev_err(imx8_phy->dev, "PCIe PLL lock timeout\n");
> > > > > +			return ret;
> > > > > +		}
> > > > > +
> > > > > +		/* pcie_clock_module_en */
> > > > > +		regmap_update_bits(imx8_phy->hsio_blk_ctrl,
> > IMX8MP_GPR_REG0,
> > > > > +				   IMX8MP_GPR_CLK_MOD_EN,
> > > > > +				   IMX8MP_GPR_CLK_MOD_EN);
> > > >
> > > > You shouldn't need to touch this bit. The HSIO blk-ctrl already
> > > > enables this bit when the PCIe power-domain is powered up.
> > > Okay, got that.
> > >
> > > >
> > > > > +		udelay(10);
> > > > > +
> > > > > +		reset_control_deassert(imx8_phy->reset);
> > > > > +		reset_control_deassert(imx8_phy->perst);
> > > > > +
> > > > > +		/* release pcie_phy_apb_reset and pcie_phy_init_resetn */
> > > > > +		regmap_update_bits(imx8_phy->hsio_blk_ctrl,
> > IMX8MP_GPR_REG0,
> > > > > +				   IMX8MP_GPR_PHY_APB_RST |
> > > > > +				   IMX8MP_GPR_PHY_INIT_RST,
> > > > > +				   IMX8MP_GPR_PHY_APB_RST |
> > > > > +				   IMX8MP_GPR_PHY_INIT_RST);
> > > >
> > > > Not sure about those yet. We might want to toggle them via a
> > > > virtual PD in the HSIO blk-ctrl.
> > > Refer to my understand, these reset should be a part of power-up
> > > sequence of
> > >  the PHY. It's reasonable to toggle them via a PD.
> >
> > So I had a chance to look into why this series isn't working for me some
> more.
> >
> > It seems the full PHY initialization fails, as the complete PHY MMIO
> > region reads back as 0xff. This hints at either a missing clock, or
> > (more likely) the register interface of the PHY being held in reset.
> > Note that I'm running upstream TF-A and the Barebox bootloader, so
> > this might be a missing initialization somewhere, that is done by
> > downstream TF-A or U-Boot.
> >
> > Sadly the above bits are also not documented in the RM, but are marked
> > as reserved. By chance, do you know about any other secondary
> > clocks/resets that may have an impact on PCIe?
> >
> Hi Lucas:
> Thanks for your help to look at this series.
> Refer to your descriptions, it seems that one initial version i.MX865 chip  is
> used at your side.
> There is a design bug in the initial version of i.MX865 PCIe. All the PHY MMIO
> region reads back as 0xff.
> It is fixed by the later chips. Find another newer board is a quick method to
> fix it. Or, apply one SW workaround to let it work only in Gen1/Gen2 modes.
> 
How does this going on? Do you find a solution that can make i.MX8MP PCIe
 works?
Please let me know if you need any information or help from me, thanks.

Best Regards
Richard Zhu

> Best Regards
> Richard Zhu
> 
> > Regards,
> > Lucas

Patch

diff --git a/drivers/phy/freescale/phy-fsl-imx8m-pcie.c b/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
index 04b1aafb29f4..3d01da4323a6 100644
--- a/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
+++ b/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
@@ -11,6 +11,8 @@ 
 #include <linux/mfd/syscon.h>
 #include <linux/mfd/syscon/imx7-iomuxc-gpr.h>
 #include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
 #include <linux/phy/phy.h>
 #include <linux/platform_device.h>
 #include <linux/regmap.h>
@@ -30,12 +32,10 @@ 
 #define IMX8MM_PCIE_PHY_CMN_REG065	0x194
 #define  ANA_AUX_RX_TERM		(BIT(7) | BIT(4))
 #define  ANA_AUX_TX_LVL			GENMASK(3, 0)
-#define IMX8MM_PCIE_PHY_CMN_REG75	0x1D4
-#define  PCIE_PHY_CMN_REG75_PLL_DONE	0x3
+#define IMX8MM_PCIE_PHY_CMN_REG075	0x1D4
+#define  ANA_PLL_DONE			0x3
 #define PCIE_PHY_TRSV_REG5		0x414
-#define  PCIE_PHY_TRSV_REG5_GEN1_DEEMP	0x2D
 #define PCIE_PHY_TRSV_REG6		0x418
-#define  PCIE_PHY_TRSV_REG6_GEN2_DEEMP	0xF
 
 #define IMX8MM_GPR_PCIE_REF_CLK_SEL	GENMASK(25, 24)
 #define IMX8MM_GPR_PCIE_REF_CLK_PLL	FIELD_PREP(IMX8MM_GPR_PCIE_REF_CLK_SEL, 0x3)
@@ -46,16 +46,43 @@ 
 #define IMX8MM_GPR_PCIE_SSC_EN		BIT(16)
 #define IMX8MM_GPR_PCIE_AUX_EN_OVERRIDE	BIT(9)
 
+#define IMX8MP_GPR_REG0			0x0
+#define IMX8MP_GPR_CLK_MOD_EN		BIT(0)
+#define IMX8MP_GPR_PHY_APB_RST		BIT(4)
+#define IMX8MP_GPR_PHY_INIT_RST		BIT(5)
+#define IMX8MP_GPR_REG1			0x4
+#define IMX8MP_GPR_PM_EN_CORE_CLK	BIT(0)
+#define IMX8MP_GPR_PLL_LOCK		BIT(13)
+#define IMX8MP_GPR_REG2			0x8
+#define IMX8MP_GPR_P_PLL_MASK		GENMASK(5, 0)
+#define IMX8MP_GPR_M_PLL_MASK		GENMASK(15, 6)
+#define IMX8MP_GPR_S_PLL_MASK		GENMASK(18, 16)
+#define IMX8MP_GPR_P_PLL		(0xc << 0)
+#define IMX8MP_GPR_M_PLL		(0x320 << 6)
+#define IMX8MP_GPR_S_PLL		(0x4 << 16)
+#define IMX8MP_GPR_REG3			0xc
+#define IMX8MP_GPR_PLL_CKE		BIT(17)
+#define IMX8MP_GPR_PLL_RST		BIT(31)
+
+enum imx8_pcie_phy_type {
+	IMX8MM,
+	IMX8MP,
+};
+
 struct imx8_pcie_phy {
 	void __iomem		*base;
+	struct device		*dev;
 	struct clk		*clk;
 	struct phy		*phy;
+	struct regmap		*hsio_blk_ctrl;
 	struct regmap		*iomuxc_gpr;
 	struct reset_control	*reset;
+	struct reset_control	*perst;
 	u32			refclk_pad_mode;
 	u32			tx_deemph_gen1;
 	u32			tx_deemph_gen2;
 	bool			clkreq_unused;
+	enum imx8_pcie_phy_type	variant;
 };
 
 static int imx8_pcie_phy_init(struct phy *phy)
@@ -67,6 +94,87 @@  static int imx8_pcie_phy_init(struct phy *phy)
 	reset_control_assert(imx8_phy->reset);
 
 	pad_mode = imx8_phy->refclk_pad_mode;
+	switch (imx8_phy->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;
+	case IMX8MP:
+		reset_control_assert(imx8_phy->perst);
+		/* Set P=12,M=800,S=4 and must set ICP=2'b01. */
+		regmap_update_bits(imx8_phy->hsio_blk_ctrl, IMX8MP_GPR_REG2,
+				   IMX8MP_GPR_P_PLL_MASK |
+				   IMX8MP_GPR_M_PLL_MASK |
+				   IMX8MP_GPR_S_PLL_MASK,
+				   IMX8MP_GPR_P_PLL |
+				   IMX8MP_GPR_M_PLL |
+				   IMX8MP_GPR_S_PLL);
+		/* wait greater than 1/F_FREF =1/2MHZ=0.5us */
+		udelay(1);
+
+		regmap_update_bits(imx8_phy->hsio_blk_ctrl, IMX8MP_GPR_REG3,
+				   IMX8MP_GPR_PLL_RST,
+				   IMX8MP_GPR_PLL_RST);
+		udelay(10);
+
+		/* Set 1 to pll_cke of GPR_REG3 */
+		regmap_update_bits(imx8_phy->hsio_blk_ctrl, IMX8MP_GPR_REG3,
+				   IMX8MP_GPR_PLL_CKE,
+				   IMX8MP_GPR_PLL_CKE);
+
+		/* Lock time should be greater than 300cycle=300*0.5us=150us */
+		ret = regmap_read_poll_timeout(imx8_phy->hsio_blk_ctrl,
+					     IMX8MP_GPR_REG1, val,
+					     val & IMX8MP_GPR_PLL_LOCK,
+					     10, 1000);
+		if (ret) {
+			dev_err(imx8_phy->dev, "PCIe PLL lock timeout\n");
+			return ret;
+		}
+
+		/* pcie_clock_module_en */
+		regmap_update_bits(imx8_phy->hsio_blk_ctrl, IMX8MP_GPR_REG0,
+				   IMX8MP_GPR_CLK_MOD_EN,
+				   IMX8MP_GPR_CLK_MOD_EN);
+		udelay(10);
+
+		reset_control_deassert(imx8_phy->reset);
+		reset_control_deassert(imx8_phy->perst);
+
+		/* release pcie_phy_apb_reset and pcie_phy_init_resetn */
+		regmap_update_bits(imx8_phy->hsio_blk_ctrl, IMX8MP_GPR_REG0,
+				   IMX8MP_GPR_PHY_APB_RST |
+				   IMX8MP_GPR_PHY_INIT_RST,
+				   IMX8MP_GPR_PHY_APB_RST |
+				   IMX8MP_GPR_PHY_INIT_RST);
+		break;
+	}
+
+	if (pad_mode == IMX8_PCIE_REFCLK_PAD_INPUT) {
+		/* Configure the pad as input */
+		val = readl(imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG061);
+		writel(val & ~ANA_PLL_CLK_OUT_TO_EXT_IO_EN,
+		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG061);
+	} else if (pad_mode == IMX8_PCIE_REFCLK_PAD_OUTPUT) {
+		/* Configure the PHY to output the refclock via pad */
+		writel(ANA_PLL_CLK_OUT_TO_EXT_IO_EN,
+		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG061);
+		writel(ANA_PLL_CLK_OUT_TO_EXT_IO_SEL,
+		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG062);
+		writel(AUX_PLL_REFCLK_SEL_SYS_PLL,
+		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG063);
+		val = ANA_AUX_RX_TX_SEL_TX | ANA_AUX_TX_TERM;
+		writel(val | ANA_AUX_RX_TERM_GND_EN,
+		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG064);
+		writel(ANA_AUX_RX_TERM | ANA_AUX_TX_LVL,
+		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG065);
+	}
+
 	/* 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,
@@ -91,42 +199,30 @@  static int imx8_pcie_phy_init(struct phy *phy)
 	regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
 			   IMX8MM_GPR_PCIE_CMN_RST,
 			   IMX8MM_GPR_PCIE_CMN_RST);
-	usleep_range(200, 500);
 
-	if (pad_mode == IMX8_PCIE_REFCLK_PAD_INPUT) {
-		/* Configure the pad as input */
-		val = readl(imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG061);
-		writel(val & ~ANA_PLL_CLK_OUT_TO_EXT_IO_EN,
-		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG061);
-	} else if (pad_mode == IMX8_PCIE_REFCLK_PAD_OUTPUT) {
-		/* Configure the PHY to output the refclock via pad */
-		writel(ANA_PLL_CLK_OUT_TO_EXT_IO_EN,
-		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG061);
-		writel(ANA_PLL_CLK_OUT_TO_EXT_IO_SEL,
-		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG062);
-		writel(AUX_PLL_REFCLK_SEL_SYS_PLL,
-		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG063);
-		val = ANA_AUX_RX_TX_SEL_TX | ANA_AUX_TX_TERM;
-		writel(val | ANA_AUX_RX_TERM_GND_EN,
-		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG064);
-		writel(ANA_AUX_RX_TERM | ANA_AUX_TX_LVL,
-		       imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG065);
+	switch (imx8_phy->variant) {
+	case IMX8MM:
+		reset_control_deassert(imx8_phy->reset);
+		usleep_range(200, 500);
+		break;
+
+	case IMX8MP:
+		/* wait for core_clk enabled */
+		ret = regmap_read_poll_timeout(imx8_phy->hsio_blk_ctrl,
+					     IMX8MP_GPR_REG1, val,
+					     val & IMX8MP_GPR_PM_EN_CORE_CLK,
+					     10, 20000);
+		if (ret) {
+			dev_err(imx8_phy->dev, "PCIe CORE CLK enable failed\n");
+			return ret;
+		}
+
+		break;
 	}
 
-	/* 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);
-
-	reset_control_deassert(imx8_phy->reset);
-
 	/* Polling to check the phy is ready or not. */
-	ret = readl_poll_timeout(imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG75,
-				 val, val == PCIE_PHY_CMN_REG75_PLL_DONE,
-				 10, 20000);
+	ret = readl_poll_timeout(imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG075,
+				 val, val == ANA_PLL_DONE, 10, 20000);
 	return ret;
 }
 
@@ -153,18 +249,33 @@  static const struct phy_ops imx8_pcie_phy_ops = {
 	.owner		= THIS_MODULE,
 };
 
+static const struct of_device_id imx8_pcie_phy_of_match[] = {
+	{.compatible = "fsl,imx8mm-pcie-phy", .data = (void *)IMX8MM},
+	{.compatible = "fsl,imx8mp-pcie-phy", .data = (void *)IMX8MP},
+	{ },
+};
+MODULE_DEVICE_TABLE(of, imx8_pcie_phy_of_match);
+
 static int imx8_pcie_phy_probe(struct platform_device *pdev)
 {
 	struct phy_provider *phy_provider;
 	struct device *dev = &pdev->dev;
+	const struct of_device_id *of_id;
 	struct device_node *np = dev->of_node;
 	struct imx8_pcie_phy *imx8_phy;
 	struct resource *res;
 
+	of_id = of_match_device(imx8_pcie_phy_of_match, dev);
+	if (!of_id)
+		return -EINVAL;
+
 	imx8_phy = devm_kzalloc(dev, sizeof(*imx8_phy), GFP_KERNEL);
 	if (!imx8_phy)
 		return -ENOMEM;
 
+	imx8_phy->dev = dev;
+	imx8_phy->variant = (enum imx8_pcie_phy_type)of_id->data;
+
 	/* get PHY refclk pad mode */
 	of_property_read_u32(np, "fsl,refclk-pad-mode",
 			     &imx8_phy->refclk_pad_mode);
@@ -201,6 +312,22 @@  static int imx8_pcie_phy_probe(struct platform_device *pdev)
 		dev_err(dev, "Failed to get PCIEPHY reset control\n");
 		return PTR_ERR(imx8_phy->reset);
 	}
+	if (imx8_phy->variant == IMX8MP) {
+		/* Grab HSIO MIX config register range */
+		imx8_phy->hsio_blk_ctrl =
+			 syscon_regmap_lookup_by_compatible("fsl,imx8mp-hsio-blk-ctrl");
+		if (IS_ERR(imx8_phy->hsio_blk_ctrl)) {
+			dev_err(dev, "unable to find hsio mix registers\n");
+			return PTR_ERR(imx8_phy->hsio_blk_ctrl);
+		}
+
+		imx8_phy->perst =
+			devm_reset_control_get_exclusive(dev, "perst");
+		if (IS_ERR(imx8_phy->perst)) {
+			dev_err(dev, "Failed to get PCIEPHY perst control\n");
+			return PTR_ERR(imx8_phy->perst);
+		}
+	}
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	imx8_phy->base = devm_ioremap_resource(dev, res);
@@ -218,12 +345,6 @@  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 = {