RE: [PATCH v10 3/4] phy: freescale: imx8m-pcie: Refine i.MX8MM PCIe PHY driver
From: Hongxing Zhu
Date: Mon Oct 03 2022 - 01:15:19 EST
> -----Original Message-----
> From: Ahmad Fatoum <a.fatoum@xxxxxxxxxxxxxx>
> Sent: 2022年9月30日 16:29
> To: Hongxing Zhu <hongxing.zhu@xxxxxxx>; vkoul@xxxxxxxxxx;
> p.zabel@xxxxxxxxxxxxxx; l.stach@xxxxxxxxxxxxxx; bhelgaas@xxxxxxxxxx;
> lorenzo.pieralisi@xxxxxxx; robh@xxxxxxxxxx; shawnguo@xxxxxxxxxx;
> alexander.stein@xxxxxxxxxxxxxxx; marex@xxxxxxx; richard.leitner@xxxxxxxxx
> Cc: devicetree@xxxxxxxxxxxxxxx; linux-pci@xxxxxxxxxxxxxxx;
> linux-kernel@xxxxxxxxxxxxxxx; dl-linux-imx <linux-imx@xxxxxxx>;
> kernel@xxxxxxxxxxxxxx; linux-phy@xxxxxxxxxxxxxxxxxxx;
> linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
> Subject: Re: [PATCH v10 3/4] phy: freescale: imx8m-pcie: Refine i.MX8MM
> PCIe PHY driver
>
> On 29.09.22 09:37, Richard Zhu wrote:
> > To make it more flexible and easy to expand. Refine i.MX8MM PCIe PHY
> > driver.
> > - Use gpr compatible string to avoid the codes duplications when add
> > another platform PCIe PHY support.
> > - Re-orange the codes to let it more flexible and easy to expand.
>
> Re-arrange
Sorry for the spell mistake. Thanks for your review comments.
>
> > No functions changes basicly.
>
> No functional change.
Got that, thanks.
>
> >
> > 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>
> > Reviewed-by: Lucas Stach <l.stach@xxxxxxxxxxxxxx>
> > ---
> > drivers/phy/freescale/phy-fsl-imx8m-pcie.c | 106
> > +++++++++++++--------
> > 1 file changed, 66 insertions(+), 40 deletions(-)
> >
> > diff --git a/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
> > b/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
> > index 2377ed307b53..59b46a4ae069 100644
> > --- a/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
> > +++ b/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
> > @@ -11,6 +11,7 @@
> > #include <linux/mfd/syscon.h>
> > #include <linux/mfd/syscon/imx7-iomuxc-gpr.h>
> > #include <linux/module.h>
> > +#include <linux/of_device.h>
> > #include <linux/phy/phy.h>
> > #include <linux/platform_device.h>
> > #include <linux/regmap.h>
> > @@ -45,6 +46,15 @@
> > #define IMX8MM_GPR_PCIE_SSC_EN BIT(16)
> > #define IMX8MM_GPR_PCIE_AUX_EN_OVERRIDE BIT(9)
> >
> > +enum imx8_pcie_phy_type {
> > + IMX8MM,
> > +};
> > +
> > +struct imx8_pcie_phy_drvdata {
> > + enum imx8_pcie_phy_type variant;
>
> Better do indentation on the member name.
Got that, would make them indent later thanks.
>
> > + const char *gpr;
> > +};
> > +
> > struct imx8_pcie_phy {
> > void __iomem *base;
> > struct clk *clk;
> > @@ -55,6 +65,7 @@ struct imx8_pcie_phy {
> > u32 tx_deemph_gen1;
> > u32 tx_deemph_gen2;
> > bool clkreq_unused;
> > + const struct imx8_pcie_phy_drvdata *drvdata;
> > };
> >
> > static int imx8_pcie_phy_init(struct phy *phy) @@ -66,31 +77,17 @@
> > static int imx8_pcie_phy_init(struct phy *phy)
> > reset_control_assert(imx8_phy->reset);
> >
> > pad_mode = imx8_phy->refclk_pad_mode;
> > - /* Set AUX_EN_OVERRIDE 1'b0, when the CLKREQ# isn't hooked */
> > - regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
> > - IMX8MM_GPR_PCIE_AUX_EN_OVERRIDE,
> > - imx8_phy->clkreq_unused ?
> > - 0 : IMX8MM_GPR_PCIE_AUX_EN_OVERRIDE);
> > - regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
> > - IMX8MM_GPR_PCIE_AUX_EN,
> > - IMX8MM_GPR_PCIE_AUX_EN);
> > - regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
> > - IMX8MM_GPR_PCIE_POWER_OFF, 0);
> > - regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
> > - IMX8MM_GPR_PCIE_SSC_EN, 0);
> > -
> > - regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
> > - IMX8MM_GPR_PCIE_REF_CLK_SEL,
> > - pad_mode == IMX8_PCIE_REFCLK_PAD_INPUT ?
> > - IMX8MM_GPR_PCIE_REF_CLK_EXT :
> > - IMX8MM_GPR_PCIE_REF_CLK_PLL);
> > - usleep_range(100, 200);
> > -
> > - /* Do the PHY common block reset */
> > - regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
> > - IMX8MM_GPR_PCIE_CMN_RST,
> > - IMX8MM_GPR_PCIE_CMN_RST);
> > - usleep_range(200, 500);
> > + switch (imx8_phy->drvdata->variant) {
> > + case IMX8MM:
> > + /* Tune PHY de-emphasis setting to pass PCIe compliance. */
> > + if (imx8_phy->tx_deemph_gen1)
> > + writel(imx8_phy->tx_deemph_gen1,
> > + imx8_phy->base + PCIE_PHY_TRSV_REG5);
> > + if (imx8_phy->tx_deemph_gen2)
> > + writel(imx8_phy->tx_deemph_gen2,
> > + imx8_phy->base + PCIE_PHY_TRSV_REG6);
> > + break;
> > + }
>
> If you say no functional change intended, I'd expect that register writes happen
> in the same sequence. It might be ok, that you do this tuning here, but I think
> it warrants a mention in the commit message why it's ok.
>
>
> Looks good otherwise. With nitpicks addressed:
>
> Reviewed-by: Ahmad Fatoum <a.fatoum@xxxxxxxxxxxxxx>
>
Got that, thanks a lot.
Best Regards
Richard Zhu
>
> --
> Pengutronix e.K. |
> |
> Steuerwalder Str. 21 |
> https://eur01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.pe
> ngutronix.de%2F&data=05%7C01%7Chongxing.zhu%40nxp.com%7C3f75
> 643ad03b406ddfbf08daa2bdd804%7C686ea1d3bc2b4c6fa92cd99c5c301635
> %7C0%7C0%7C638001233500315244%7CUnknown%7CTWFpbGZsb3d8eyJW
> IjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3
> 000%7C%7C%7C&sdata=6NPsGMBN8culT%2BjIWtay0qT0o4L66lnmOtXI
> 4fo7z0M%3D&reserved=0 |
> 31137 Hildesheim, Germany | Phone:
> +49-5121-206917-0 |
> Amtsgericht Hildesheim, HRA 2686 | Fax:
> +49-5121-206917-5555 |