[PATCH v5 6/7] phy: freescale: imx8m-pcie: Add iMX8MP PCIe PHY support
Lucas Stach
l.stach at pengutronix.de
Wed Aug 31 01:34:09 PDT 2022
Am Mittwoch, dem 31.08.2022 um 06:16 +0000 schrieb Hongxing Zhu:
> > -----Original Message-----
> > From: Lucas Stach <l.stach at pengutronix.de>
> > Sent: 2022年8月30日 21:07
> > To: Hongxing Zhu <hongxing.zhu at nxp.com>; p.zabel at pengutronix.de;
> > bhelgaas at google.com; lorenzo.pieralisi at arm.com; robh at kernel.org;
> > shawnguo at kernel.org; vkoul at kernel.org;
> > alexander.stein at ew.tq-group.com;
> > marex at denx.de; richard.leitner at linux.dev
> > Cc: 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 v5 6/7] phy: freescale: imx8m-pcie: Add iMX8MP
> > PCIe PHY
> > support
> >
> > Am Dienstag, dem 30.08.2022 um 15:46 +0800 schrieb Richard Zhu:
> > > Add i.MX8MP PCIe PHY support.
> > >
> > > 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>
> > > ---
> > > drivers/phy/freescale/phy-fsl-imx8m-pcie.c | 137
> > > +++++++++++++--------
> > > 1 file changed, 89 insertions(+), 48 deletions(-)
> > >
> > > diff --git a/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
> > > b/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
> > > index ad7d2edfc414..c76e3a1a5f51 100644
> > > --- a/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
> > > +++ b/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
> > > @@ -11,6 +11,9 @@
> > > #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/of_device.h>
> > > #include <linux/phy/phy.h>
> > > #include <linux/platform_device.h>
> > > #include <linux/regmap.h>
> > > @@ -31,12 +34,10 @@
> > > #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)
> > > @@ -47,16 +48,23 @@
> > > #define IMX8MM_GPR_PCIE_SSC_EN BIT(16)
> > > #define IMX8MM_GPR_PCIE_AUX_EN_OVERRIDE BIT(9)
> > >
> > > +enum imx8_pcie_phy_type {
> > > + IMX8MM,
> > > + IMX8MP,
> > > +};
> > > +
> > > struct imx8_pcie_phy {
> > > void __iomem *base;
> > > struct clk *clk;
> > > struct phy *phy;
> > > 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) @@ -68,31 +76,20
> > > @@
> > > 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->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);
> > > + break;
> > > + }
> > >
> > > if (pad_mode == IMX8_PCIE_REFCLK_PAD_INPUT ||
> > > pad_mode == IMX8_PCIE_REFCLK_PAD_UNUSED) { @@ -
> > > 120,20
> > +117,44 @@
> > > 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);
> > > +
> > > + 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);
> > >
> > > - reset_control_deassert(imx8_phy->reset);
> > > + switch (imx8_phy->variant) {
> > > + case IMX8MP:
> > > + reset_control_deassert(imx8_phy->perst);
> > > + fallthrough;
> > > + 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_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;
> > > }
> > >
> > > @@ -160,6 +181,13 @@ 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;
> > > @@ -172,6 +200,9 @@ static int imx8_pcie_phy_probe(struct
> > platform_device *pdev)
> > > if (!imx8_phy)
> > > return -ENOMEM;
> > >
> > > + imx8_phy->variant =
> > > + (enum
> > > imx8_pcie_phy_type)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);
> > > @@ -196,8 +227,16 @@ 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");
> > > + switch (imx8_phy->variant) {
> > > + case IMX8MM:
> > > + imx8_phy->iomuxc_gpr =
> > > +
> > syscon_regmap_lookup_by_compatible("fsl,imx8mm-iomuxc-gpr");
> > > + break;
> > > + case IMX8MP:
> > > + imx8_phy->iomuxc_gpr =
> > > +
> > syscon_regmap_lookup_by_compatible("fsl,imx8mp-iomuxc-gpr");
> > > + break;
> > > + }
> >
> > Oh, I had a real phandle in DT in mind for this, but I see how this
> > would be
> > hard to introduce in a backward compatible manner for the 8MM.
> > At least this way it is fully contained in the driver and doesn't
> > leak into DT
> > compatibles.
> >
> > Maybe we could make this a little nicer by just having an const
> > array of iomux
> > syscon compatibles indexed by imx8_phy->variant, to avoid the
> > switch and the
> > resulting code (almost-)duplication.
> >
> Hi Lucas:
> Thanks for your comments.
> Do you mean a drvdata struct indexed by variant, and contains the
> const array
> of iomux syscon compatible like below?
>
> +static const struct imx8_pcie_phy_drvdata drvdata[] = {
> + [IMX8MM] = {
> + .variant = IMX8MM,
> + .gpr = "fsl,imx8mm-iomuxc-gpr",
> + },
> +
> + [IMX8MP] = {
> + .variant = IMX8MP,
> + .gpr = "fsl,imx8mp-iomuxc-gpr",
> + },
> +};
> +
>
> Then, we can get the drvdata, and find the according gpr syscon
> regmap below.
>
> + imx8_phy->drvdata = of_device_get_match_data(dev);
> ...
> + imx8_phy->iomuxc_gpr =
> + syscon_regmap_lookup_by_compatible(imx8_phy-
> >drvdata->gpr);
>
I had a simple array of GPR compatible strings in mind, so we could
lookup the compatible from the variant. But I think putting it directly
in drvdata, like done in your suggestion above, looks even better.
> If yes, I would do the changes, and issue the v6 later.
Yep, please change as suggested above. Same comment applies to the next
patch "PCI: imx6: Add iMX8MP PCIe support".
Also in both patches the dot between i and MX in i.MX8MP is missing in
the patch description subject line.
Regards,
Lucas
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