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SubjectRe: [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

> No functions changes basicly.

No functional change.

>
> Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>
> Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
> Tested-by: Marek Vasut <marex@denx.de>
> Tested-by: Richard Leitner <richard.leitner@skidata.com>
> Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com>
> Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
> ---
> 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.

> + 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@pengutronix.de>


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