> -----Original Message-----
> From: Lucas Stach <l.stach@xxxxxxxxxxxxxx>
> Sent: 2022年8月30日 21:07
> To: Hongxing Zhu <hongxing.zhu@xxxxxxx>; p.zabel@xxxxxxxxxxxxxx;
> bhelgaas@xxxxxxxxxx; lorenzo.pieralisi@xxxxxxx; robh@xxxxxxxxxx;
> shawnguo@xxxxxxxxxx; vkoul@xxxxxxxxxx; alexander.stein@xxxxxxxxxxxxxxx;
> marex@xxxxxxx; richard.leitner@xxxxxxxxx
> Cc: linux-phy@xxxxxxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx;
> linux-pci@xxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx;
> linux-kernel@xxxxxxxxxxxxxxx; kernel@xxxxxxxxxxxxxx; dl-linux-imx
> <linux-imx@xxxxxxx>
> 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@xxxxxxx>
> > Signed-off-by: Lucas Stach <l.stach@xxxxxxxxxxxxxx>
> > Tested-by: Marek Vasut <marex@xxxxxxx>
> > Tested-by: Richard Leitner <richard.leitner@xxxxxxxxxxx>
> > Tested-by: Alexander Stein <alexander.stein@xxxxxxxxxxxxxxx>
> > ---
> > 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);
If yes, I would do the changes, and issue the v6 later.
Best Regards
Richard Zhu
> Regards,
> Lucas
>
> > if (IS_ERR(imx8_phy->iomuxc_gpr)) {
> > dev_err(dev, "unable to find iomuxc registers\n");
> > return PTR_ERR(imx8_phy->iomuxc_gpr); @@ -208,6 +247,14 @@
> 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) {
> > + imx8_phy->perst =
> > + devm_reset_control_get_exclusive(dev, "perst");
> > + if (IS_ERR(imx8_phy->perst)) {
> > + dev_err(dev, "Failed to get PCIE PHY 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); @@ -225,12 +272,6
> > @@ 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 = {
>
