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Date:   Mon, 24 Jul 2023 16:21:45 +0530
From:   Vinod Koul <vkoul@kernel.org>
To:     Sandor Yu <Sandor.yu@nxp.com>
Cc:     andrzej.hajda@intel.com, neil.armstrong@linaro.org,
        Laurent.pinchart@ideasonboard.com, jonas@kwiboo.se,
        jernej.skrabec@gmail.com, airlied@gmail.com, daniel@ffwll.ch,
        robh+dt@kernel.org, krzysztof.kozlowski+dt@linaro.org,
        shawnguo@kernel.org, s.hauer@pengutronix.de, festevam@gmail.com,
        dri-devel@lists.freedesktop.org, devicetree@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        linux-phy@lists.infradead.org, kernel@pengutronix.de,
        linux-imx@nxp.com, oliver.brown@nxp.com,
        alexander.stein@ew.tq-group.com, sam@ravnborg.org
Subject: Re: [PATCH v7 6/7] phy: freescale: Add DisplayPort PHY driver for
 i.MX8MQ
Message-ID: <ZL5XwX99EI4RDpov@matsya>
References: <cover.1689580812.git.Sandor.yu@nxp.com>
 <50f342972001f079a0946f7718c6e3fa6aed9503.1689580812.git.Sandor.yu@nxp.com>
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On 17-07-23, 16:03, Sandor Yu wrote:
> Add Cadence HDP-TX DisplayPort PHY driver for i.MX8MQ
> 
> Cadence HDP-TX PHY could be put in either DP mode or
> HDMI mode base on the configuration chosen.
> DisplayPort PHY mode is configurated in the driver.
> 
> Signed-off-by: Sandor Yu <Sandor.yu@nxp.com>
> ---
>  drivers/phy/freescale/Kconfig             |   9 +
>  drivers/phy/freescale/Makefile            |   1 +
>  drivers/phy/freescale/phy-fsl-imx8mq-dp.c | 698 ++++++++++++++++++++++
>  3 files changed, 708 insertions(+)
>  create mode 100644 drivers/phy/freescale/phy-fsl-imx8mq-dp.c
> 
> diff --git a/drivers/phy/freescale/Kconfig b/drivers/phy/freescale/Kconfig
> index 853958fb2c06..2999ba1e57d0 100644
> --- a/drivers/phy/freescale/Kconfig
> +++ b/drivers/phy/freescale/Kconfig
> @@ -35,6 +35,15 @@ config PHY_FSL_IMX8M_PCIE
>  	  Enable this to add support for the PCIE PHY as found on
>  	  i.MX8M family of SOCs.
>  
> +config PHY_FSL_IMX8MQ_DP_PHY
> +	tristate "Freescale i.MX8MQ DP PHY support"
> +	depends on OF && HAS_IOMEM
> +	depends on COMMON_CLK
> +	select GENERIC_PHY
> +	help
> +	  Enable this to support the Cadence HDPTX DP PHY driver
> +	  on i.MX8MQ SOC.
> +
>  endif
>  
>  config PHY_FSL_LYNX_28G
> diff --git a/drivers/phy/freescale/Makefile b/drivers/phy/freescale/Makefile
> index cedb328bc4d2..915a429d9fbc 100644
> --- a/drivers/phy/freescale/Makefile
> +++ b/drivers/phy/freescale/Makefile
> @@ -4,3 +4,4 @@ obj-$(CONFIG_PHY_MIXEL_LVDS_PHY)	+= phy-fsl-imx8qm-lvds-phy.o
>  obj-$(CONFIG_PHY_MIXEL_MIPI_DPHY)	+= phy-fsl-imx8-mipi-dphy.o
>  obj-$(CONFIG_PHY_FSL_IMX8M_PCIE)	+= phy-fsl-imx8m-pcie.o
>  obj-$(CONFIG_PHY_FSL_LYNX_28G)		+= phy-fsl-lynx-28g.o
> +obj-$(CONFIG_PHY_FSL_IMX8MQ_DP_PHY)	+= phy-fsl-imx8mq-dp.o
> diff --git a/drivers/phy/freescale/phy-fsl-imx8mq-dp.c b/drivers/phy/freescale/phy-fsl-imx8mq-dp.c
> new file mode 100644
> index 000000000000..415273ac6aa5
> --- /dev/null
> +++ b/drivers/phy/freescale/phy-fsl-imx8mq-dp.c
> @@ -0,0 +1,698 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Cadence HDP-TX Display Port Interface (DP) PHY driver
> + *
> + * Copyright (C) 2022 NXP Semiconductor, Inc.
> + */
> +#include <asm/unaligned.h>
> +#include <linux/clk.h>
> +#include <linux/kernel.h>
> +#include <linux/phy/phy.h>
> +#include <linux/platform_device.h>
> +#include <linux/io.h>
> +#include <linux/iopoll.h>
> +
> +#include <drm/bridge/cdns-mhdp-mailbox.h>
> +
> +#define ADDR_PHY_AFE	0x80000
> +
> +/* PHY registers */
> +#define CMN_SSM_BIAS_TMR                0x0022
> +#define CMN_PLLSM0_PLLEN_TMR            0x0029
> +#define CMN_PLLSM0_PLLPRE_TMR           0x002a
> +#define CMN_PLLSM0_PLLVREF_TMR          0x002b
> +#define CMN_PLLSM0_PLLLOCK_TMR          0x002c
> +#define CMN_PLLSM0_USER_DEF_CTRL        0x002f
> +#define CMN_PSM_CLK_CTRL                0x0061
> +#define CMN_PLL0_VCOCAL_START           0x0081
> +#define CMN_PLL0_VCOCAL_INIT_TMR        0x0084
> +#define CMN_PLL0_VCOCAL_ITER_TMR        0x0085
> +#define CMN_PLL0_INTDIV                 0x0094
> +#define CMN_PLL0_FRACDIV                0x0095
> +#define CMN_PLL0_HIGH_THR               0x0096
> +#define CMN_PLL0_DSM_DIAG               0x0097
> +#define CMN_PLL0_SS_CTRL2               0x0099
> +#define CMN_ICAL_INIT_TMR               0x00c4
> +#define CMN_ICAL_ITER_TMR               0x00c5
> +#define CMN_RXCAL_INIT_TMR              0x00d4
> +#define CMN_RXCAL_ITER_TMR              0x00d5
> +#define CMN_TXPUCAL_INIT_TMR            0x00e4
> +#define CMN_TXPUCAL_ITER_TMR            0x00e5
> +#define CMN_TXPDCAL_INIT_TMR            0x00f4
> +#define CMN_TXPDCAL_ITER_TMR            0x00f5
> +#define CMN_ICAL_ADJ_INIT_TMR           0x0102
> +#define CMN_ICAL_ADJ_ITER_TMR           0x0103
> +#define CMN_RX_ADJ_INIT_TMR             0x0106
> +#define CMN_RX_ADJ_ITER_TMR             0x0107
> +#define CMN_TXPU_ADJ_INIT_TMR           0x010a
> +#define CMN_TXPU_ADJ_ITER_TMR           0x010b
> +#define CMN_TXPD_ADJ_INIT_TMR           0x010e
> +#define CMN_TXPD_ADJ_ITER_TMR           0x010f
> +#define CMN_DIAG_PLL0_FBH_OVRD          0x01c0
> +#define CMN_DIAG_PLL0_FBL_OVRD          0x01c1
> +#define CMN_DIAG_PLL0_OVRD              0x01c2
> +#define CMN_DIAG_PLL0_TEST_MODE         0x01c4
> +#define CMN_DIAG_PLL0_V2I_TUNE          0x01c5
> +#define CMN_DIAG_PLL0_CP_TUNE           0x01c6
> +#define CMN_DIAG_PLL0_LF_PROG           0x01c7
> +#define CMN_DIAG_PLL0_PTATIS_TUNE1      0x01c8
> +#define CMN_DIAG_PLL0_PTATIS_TUNE2      0x01c9
> +#define CMN_DIAG_HSCLK_SEL              0x01e0
> +#define CMN_DIAG_PER_CAL_ADJ            0x01ec
> +#define CMN_DIAG_CAL_CTRL               0x01ed
> +#define CMN_DIAG_ACYA                   0x01ff
> +#define XCVR_PSM_RCTRL                  0x4001
> +#define XCVR_PSM_CAL_TMR                0x4002
> +#define XCVR_PSM_A0IN_TMR               0x4003
> +#define TX_TXCC_CAL_SCLR_MULT_0         0x4047
> +#define TX_TXCC_CPOST_MULT_00_0         0x404c
> +#define XCVR_DIAG_PLLDRC_CTRL           0x40e0
> +#define XCVR_DIAG_PLLDRC_CTRL           0x40e0
> +#define XCVR_DIAG_HSCLK_SEL             0x40e1
> +#define XCVR_DIAG_LANE_FCM_EN_MGN_TMR   0x40f2
> +#define TX_PSC_A0                       0x4100
> +#define TX_PSC_A1                       0x4101
> +#define TX_PSC_A2                       0x4102
> +#define TX_PSC_A3                       0x4103
> +#define TX_RCVDET_EN_TMR                0x4122
> +#define TX_RCVDET_ST_TMR                0x4123
> +#define TX_DIAG_BGREF_PREDRV_DELAY      0x41e7
> +#define TX_DIAG_BGREF_PREDRV_DELAY      0x41e7
> +#define TX_DIAG_ACYA_0                  0x41ff
> +#define TX_DIAG_ACYA_1                  0x43ff
> +#define TX_DIAG_ACYA_2                  0x45ff
> +#define TX_DIAG_ACYA_3                  0x47ff
> +#define TX_ANA_CTRL_REG_1               0x5020
> +#define TX_ANA_CTRL_REG_2               0x5021
> +#define TX_DIG_CTRL_REG_1               0x5023
> +#define TX_DIG_CTRL_REG_2               0x5024
> +#define TXDA_CYA_AUXDA_CYA              0x5025
> +#define TX_ANA_CTRL_REG_3               0x5026
> +#define TX_ANA_CTRL_REG_4               0x5027
> +#define TX_ANA_CTRL_REG_5               0x5029
> +#define RX_PSC_A0                       0x8000
> +#define RX_PSC_CAL                      0x8006
> +#define PHY_HDP_MODE_CTRL               0xc008
> +#define PHY_HDP_CLK_CTL                 0xc009
> +#define PHY_PMA_CMN_CTRL1               0xc800
> +
> +#define REF_CLK_27MHZ		27000000
> +
> +enum dp_link_rate {
> +	RATE_1_6 = 162000,
> +	RATE_2_1 = 216000,
> +	RATE_2_4 = 243000,
> +	RATE_2_7 = 270000,
> +	RATE_3_2 = 324000,
> +	RATE_4_3 = 432000,
> +	RATE_5_4 = 540000,
> +	RATE_8_1 = 810000,
> +};
> +
> +#define MAX_LINK_RATE RATE_5_4
> +
> +struct phy_pll_reg {
> +	u16 val[7];
> +	u32 addr;
> +};
> +
> +static const struct phy_pll_reg phy_pll_27m_cfg[] = {
> +	/*  1.62    2.16    2.43    2.7     3.24    4.32    5.4      register address */
> +	{{ 0x010e, 0x010e, 0x010e, 0x010e, 0x010e, 0x010e, 0x010e }, CMN_PLL0_VCOCAL_INIT_TMR },
> +	{{ 0x001b, 0x001b, 0x001b, 0x001b, 0x001b, 0x001b, 0x001b }, CMN_PLL0_VCOCAL_ITER_TMR },
> +	{{ 0x30b9, 0x3087, 0x3096, 0x30b4, 0x30b9, 0x3087, 0x30b4 }, CMN_PLL0_VCOCAL_START },
> +	{{ 0x0077, 0x009f, 0x00b3, 0x00c7, 0x0077, 0x009f, 0x00c7 }, CMN_PLL0_INTDIV },
> +	{{ 0xf9da, 0xf7cd, 0xf6c7, 0xf5c1, 0xf9da, 0xf7cd, 0xf5c1 }, CMN_PLL0_FRACDIV },
> +	{{ 0x001e, 0x0028, 0x002d, 0x0032, 0x001e, 0x0028, 0x0032 }, CMN_PLL0_HIGH_THR },
> +	{{ 0x0020, 0x0020, 0x0020, 0x0020, 0x0020, 0x0020, 0x0020 }, CMN_PLL0_DSM_DIAG },
> +	{{ 0x0000, 0x1000, 0x1000, 0x1000, 0x0000, 0x1000, 0x1000 }, CMN_PLLSM0_USER_DEF_CTRL },
> +	{{ 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000 }, CMN_DIAG_PLL0_OVRD },
> +	{{ 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000 }, CMN_DIAG_PLL0_FBH_OVRD },
> +	{{ 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000 }, CMN_DIAG_PLL0_FBL_OVRD },
> +	{{ 0x0006, 0x0007, 0x0007, 0x0007, 0x0006, 0x0007, 0x0007 }, CMN_DIAG_PLL0_V2I_TUNE },
> +	{{ 0x0043, 0x0043, 0x0043, 0x0042, 0x0043, 0x0043, 0x0042 }, CMN_DIAG_PLL0_CP_TUNE },
> +	{{ 0x0008, 0x0008, 0x0008, 0x0008, 0x0008, 0x0008, 0x0008 }, CMN_DIAG_PLL0_LF_PROG },
> +	{{ 0x0100, 0x0001, 0x0001, 0x0001, 0x0100, 0x0001, 0x0001 }, CMN_DIAG_PLL0_PTATIS_TUNE1 },
> +	{{ 0x0007, 0x0001, 0x0001, 0x0001, 0x0007, 0x0001, 0x0001 }, CMN_DIAG_PLL0_PTATIS_TUNE2 },
> +	{{ 0x0020, 0x0020, 0x0020, 0x0020, 0x0020, 0x0020, 0x0020 }, CMN_DIAG_PLL0_TEST_MODE},
> +	{{ 0x0016, 0x0016, 0x0016, 0x0016, 0x0016, 0x0016, 0x0016 }, CMN_PSM_CLK_CTRL }
> +};
> +
> +struct cdns_hdptx_dp_phy {
> +	void __iomem *regs;	/* DPTX registers base */
> +	struct device *dev;
> +	struct phy *phy;
> +	struct mutex mbox_mutex;	/* mutex to protect mailbox */
> +	struct clk *ref_clk, *apb_clk;
> +	u32 ref_clk_rate;
> +	u32 num_lanes;
> +	u32 link_rate;
> +	bool power_up;
> +};
> +
> +static int cdns_phy_reg_write(struct cdns_hdptx_dp_phy *cdns_phy, u32 addr, u32 val)
> +{
> +	return cdns_mhdp_reg_write(cdns_phy, ADDR_PHY_AFE + (addr << 2), val);
> +}
> +
> +static u32 cdns_phy_reg_read(struct cdns_hdptx_dp_phy *cdns_phy, u32 addr)
> +{
> +	u32 reg32;
> +
> +	cdns_mhdp_reg_read(cdns_phy, ADDR_PHY_AFE + (addr << 2), &reg32);
> +	return reg32;
> +}
> +
> +static int link_rate_index(u32 rate)
> +{
> +	switch (rate) {
> +	case RATE_1_6:
> +		return 0;
> +	case RATE_2_1:
> +		return 1;
> +	case RATE_2_4:
> +		return 2;
> +	case RATE_2_7:
> +		return 3;
> +	case RATE_3_2:
> +		return 4;
> +	case RATE_4_3:
> +		return 5;
> +	case RATE_5_4:
> +		return 6;
> +	default:
> +		return -1;
> +	}
> +}
> +
> +static int hdptx_dp_clk_enable(struct cdns_hdptx_dp_phy *cdns_phy)
> +{
> +	struct device *dev = cdns_phy->dev;
> +	u32 ref_clk_rate;
> +	int ret;
> +
> +	cdns_phy->ref_clk = devm_clk_get(dev, "ref");
> +	if (IS_ERR(cdns_phy->ref_clk)) {
> +		dev_err(dev, "phy ref clock not found\n");
> +		return PTR_ERR(cdns_phy->ref_clk);
> +	}
> +
> +	cdns_phy->apb_clk = devm_clk_get(dev, "apb");
> +	if (IS_ERR(cdns_phy->apb_clk)) {
> +		dev_err(dev, "phy apb clock not found\n");
> +		return PTR_ERR(cdns_phy->apb_clk);
> +	}
> +
> +	ret = clk_prepare_enable(cdns_phy->ref_clk);
> +	if (ret) {
> +		dev_err(cdns_phy->dev, "Failed to prepare ref clock\n");
> +		return ret;
> +	}
> +
> +	ref_clk_rate = clk_get_rate(cdns_phy->ref_clk);
> +	if (!ref_clk_rate) {
> +		dev_err(cdns_phy->dev, "Failed to get ref clock rate\n");
> +		goto err_ref_clk;
> +	}
> +
> +	if (ref_clk_rate == REF_CLK_27MHZ) {
> +		cdns_phy->ref_clk_rate = ref_clk_rate;
> +	} else {
> +		dev_err(cdns_phy->dev, "Not support Ref Clock Rate(%dHz)\n", ref_clk_rate);
> +		goto err_ref_clk;
> +	}
> +
> +	ret = clk_prepare_enable(cdns_phy->apb_clk);
> +	if (ret) {
> +		dev_err(cdns_phy->dev, "Failed to prepare apb clock\n");
> +		goto err_ref_clk;
> +	}
> +
> +	return 0;
> +
> +err_ref_clk:
> +	clk_disable_unprepare(cdns_phy->ref_clk);
> +	return -EINVAL;
> +}
> +
> +static void hdptx_dp_clk_disable(struct cdns_hdptx_dp_phy *cdns_phy)
> +{
> +	clk_disable_unprepare(cdns_phy->ref_clk);
> +	clk_disable_unprepare(cdns_phy->apb_clk);
> +}
> +
> +static void hdptx_dp_aux_cfg(struct cdns_hdptx_dp_phy *cdns_phy)
> +{
> +	/* Power up Aux */
> +	cdns_phy_reg_write(cdns_phy, TXDA_CYA_AUXDA_CYA, 1);
> +
> +	cdns_phy_reg_write(cdns_phy, TX_DIG_CTRL_REG_1, 0x3);
> +	ndelay(150);
> +	cdns_phy_reg_write(cdns_phy, TX_DIG_CTRL_REG_2, 36);
> +	ndelay(150);
> +	cdns_phy_reg_write(cdns_phy, TX_ANA_CTRL_REG_2, 0x0100);
> +	ndelay(150);
> +	cdns_phy_reg_write(cdns_phy, TX_ANA_CTRL_REG_2, 0x0300);
> +	ndelay(150);
> +	cdns_phy_reg_write(cdns_phy, TX_ANA_CTRL_REG_3, 0x0000);
> +	ndelay(150);
> +	cdns_phy_reg_write(cdns_phy, TX_ANA_CTRL_REG_1, 0x2008);
> +	ndelay(150);
> +	cdns_phy_reg_write(cdns_phy, TX_ANA_CTRL_REG_1, 0x2018);
> +	ndelay(150);
> +	cdns_phy_reg_write(cdns_phy, TX_ANA_CTRL_REG_1, 0xa018);
> +	ndelay(150);
> +	cdns_phy_reg_write(cdns_phy, TX_ANA_CTRL_REG_2, 0x030c);
> +	ndelay(150);
> +	cdns_phy_reg_write(cdns_phy, TX_ANA_CTRL_REG_5, 0x0000);
> +	ndelay(150);
> +	cdns_phy_reg_write(cdns_phy, TX_ANA_CTRL_REG_4, 0x1001);
> +	ndelay(150);
> +	cdns_phy_reg_write(cdns_phy, TX_ANA_CTRL_REG_1, 0xa098);
> +	ndelay(150);
> +	cdns_phy_reg_write(cdns_phy, TX_ANA_CTRL_REG_1, 0xa198);
> +	ndelay(150);
> +	cdns_phy_reg_write(cdns_phy, TX_ANA_CTRL_REG_2, 0x030d);
> +	ndelay(150);
> +	cdns_phy_reg_write(cdns_phy, TX_ANA_CTRL_REG_2, 0x030f);
> +}
> +
> +/* PMA common configuration for 27MHz */
> +static void hdptx_dp_phy_pma_cmn_cfg_27mhz(struct cdns_hdptx_dp_phy *cdns_phy)
> +{
> +	u32 num_lanes = cdns_phy->num_lanes;
> +	u16 val;
> +	int k;
> +
> +	val = cdns_phy_reg_read(cdns_phy, PHY_PMA_CMN_CTRL1);
> +	val &= 0xfff7;
> +	val |= 0x0008;

magic numbers? also pls use FIELD_PRE() to set bitfields

> +	cdns_phy_reg_write(cdns_phy, PHY_PMA_CMN_CTRL1, val);
> +
> +	/* Startup state machine registers */
> +	cdns_phy_reg_write(cdns_phy, CMN_SSM_BIAS_TMR, 0x0087);
> +	cdns_phy_reg_write(cdns_phy, CMN_PLLSM0_PLLEN_TMR, 0x001b);
> +	cdns_phy_reg_write(cdns_phy, CMN_PLLSM0_PLLPRE_TMR, 0x0036);
> +	cdns_phy_reg_write(cdns_phy, CMN_PLLSM0_PLLVREF_TMR, 0x001b);
> +	cdns_phy_reg_write(cdns_phy, CMN_PLLSM0_PLLLOCK_TMR, 0x006c);
> +
> +	/* Current calibration registers */
> +	cdns_phy_reg_write(cdns_phy, CMN_ICAL_INIT_TMR, 0x0044);
> +	cdns_phy_reg_write(cdns_phy, CMN_ICAL_ITER_TMR, 0x0006);
> +	cdns_phy_reg_write(cdns_phy, CMN_ICAL_ADJ_INIT_TMR, 0x0022);
> +	cdns_phy_reg_write(cdns_phy, CMN_ICAL_ADJ_ITER_TMR, 0x0006);
> +
> +	/* Resistor calibration registers */
> +	cdns_phy_reg_write(cdns_phy, CMN_TXPUCAL_INIT_TMR, 0x0022);
> +	cdns_phy_reg_write(cdns_phy, CMN_TXPUCAL_ITER_TMR, 0x0006);
> +	cdns_phy_reg_write(cdns_phy, CMN_TXPU_ADJ_INIT_TMR, 0x0022);
> +	cdns_phy_reg_write(cdns_phy, CMN_TXPU_ADJ_ITER_TMR, 0x0006);
> +	cdns_phy_reg_write(cdns_phy, CMN_TXPDCAL_INIT_TMR, 0x0022);
> +	cdns_phy_reg_write(cdns_phy, CMN_TXPDCAL_ITER_TMR, 0x0006);
> +	cdns_phy_reg_write(cdns_phy, CMN_TXPD_ADJ_INIT_TMR, 0x0022);
> +	cdns_phy_reg_write(cdns_phy, CMN_TXPD_ADJ_ITER_TMR, 0x0006);
> +	cdns_phy_reg_write(cdns_phy, CMN_RXCAL_INIT_TMR, 0x0022);
> +	cdns_phy_reg_write(cdns_phy, CMN_RXCAL_ITER_TMR, 0x0006);
> +	cdns_phy_reg_write(cdns_phy, CMN_RX_ADJ_INIT_TMR, 0x0022);
> +	cdns_phy_reg_write(cdns_phy, CMN_RX_ADJ_ITER_TMR, 0x0006);
> +
> +	for (k = 0; k < num_lanes; k = k + 1) {
> +		/* Power state machine registers */
> +		cdns_phy_reg_write(cdns_phy, XCVR_PSM_CAL_TMR  | (k << 9), 0x016d);
> +		cdns_phy_reg_write(cdns_phy, XCVR_PSM_A0IN_TMR | (k << 9), 0x016d);
> +		/* Transceiver control and diagnostic registers */
> +		cdns_phy_reg_write(cdns_phy, XCVR_DIAG_LANE_FCM_EN_MGN_TMR | (k << 9), 0x00a2);
> +		cdns_phy_reg_write(cdns_phy, TX_DIAG_BGREF_PREDRV_DELAY | (k << 9), 0x0097);
> +		/* Transmitter receiver detect registers */
> +		cdns_phy_reg_write(cdns_phy, TX_RCVDET_EN_TMR | (k << 9), 0x0a8c);
> +		cdns_phy_reg_write(cdns_phy, TX_RCVDET_ST_TMR | (k << 9), 0x0036);
> +	}
> +
> +	cdns_phy_reg_write(cdns_phy, TX_DIAG_ACYA_0, 1);
> +	cdns_phy_reg_write(cdns_phy, TX_DIAG_ACYA_1, 1);
> +	cdns_phy_reg_write(cdns_phy, TX_DIAG_ACYA_2, 1);
> +	cdns_phy_reg_write(cdns_phy, TX_DIAG_ACYA_3, 1);
> +}
> +
> +static void hdptx_dp_phy_pma_cmn_pll0_27mhz(struct cdns_hdptx_dp_phy *cdns_phy)
> +{
> +	u32 num_lanes = cdns_phy->num_lanes;
> +	u32 link_rate = cdns_phy->link_rate;
> +	u16 val;
> +	int index, i, k;
> +
> +	/* DP PLL data rate 0/1 clock divider value */
> +	val = cdns_phy_reg_read(cdns_phy, PHY_HDP_CLK_CTL);
> +	val &= 0x00ff;
> +	if (link_rate <= RATE_2_7)
> +		val |= 0x2400;
> +	else
> +		val |= 0x1200;

more magic?

> +	cdns_phy_reg_write(cdns_phy, PHY_HDP_CLK_CTL, val);
> +
> +	/* High speed clock 0/1 div */
> +	val = cdns_phy_reg_read(cdns_phy, CMN_DIAG_HSCLK_SEL);
> +	val &= 0xffcc;

and here

> +	if (link_rate <= RATE_2_7)
> +		val |= 0x0011;
> +	cdns_phy_reg_write(cdns_phy, CMN_DIAG_HSCLK_SEL, val);
> +
> +	for (k = 0; k < num_lanes; k++) {
> +		val = cdns_phy_reg_read(cdns_phy, (XCVR_DIAG_HSCLK_SEL | (k << 9)));
> +		val = val & 0xcfff;
> +		if (link_rate <= RATE_2_7)
> +			val |= 0x1000;
> +		cdns_phy_reg_write(cdns_phy, (XCVR_DIAG_HSCLK_SEL | (k << 9)), val);
> +	}
> +
> +	/* DP PHY PLL 27MHz configuration */
> +	index = link_rate_index(link_rate);
> +	for (i = 0; i < ARRAY_SIZE(phy_pll_27m_cfg); i++)
> +		cdns_phy_reg_write(cdns_phy, phy_pll_27m_cfg[i].addr,
> +				   phy_pll_27m_cfg[i].val[index]);
> +
> +	/* Transceiver control and diagnostic registers */
> +	for (k = 0; k < num_lanes; k++) {
> +		val = cdns_phy_reg_read(cdns_phy, (XCVR_DIAG_PLLDRC_CTRL | (k << 9)));
> +		val = val & 0x8fff;
> +		if (link_rate <= RATE_2_7)
> +			val |= 0x2000;
> +		else
> +			val |= 0x1000;
> +		cdns_phy_reg_write(cdns_phy, (XCVR_DIAG_PLLDRC_CTRL | (k << 9)), val);
> +	}
> +
> +	for (k = 0; k < num_lanes; k = k + 1) {
> +		/* Power state machine registers */
> +		cdns_phy_reg_write(cdns_phy, (XCVR_PSM_RCTRL | (k << 9)), 0xbefc);
> +		cdns_phy_reg_write(cdns_phy, (TX_PSC_A0 | (k << 9)), 0x6799);
> +		cdns_phy_reg_write(cdns_phy, (TX_PSC_A1 | (k << 9)), 0x6798);
> +		cdns_phy_reg_write(cdns_phy, (TX_PSC_A2 | (k << 9)), 0x0098);
> +		cdns_phy_reg_write(cdns_phy, (TX_PSC_A3 | (k << 9)), 0x0098);
> +		/* Receiver calibration power state definition register */
> +		val = cdns_phy_reg_read(cdns_phy, RX_PSC_CAL | (k << 9));
> +		val &= 0xffbb;
> +		cdns_phy_reg_write(cdns_phy, (RX_PSC_CAL | (k << 9)), val);
> +		val = cdns_phy_reg_read(cdns_phy, RX_PSC_A0 | (k << 9));
> +		val &= 0xffbb;
> +		cdns_phy_reg_write(cdns_phy, (RX_PSC_A0 | (k << 9)), val);
> +	}
> +}
> +
> +static void hdptx_dp_phy_ref_clock_type(struct cdns_hdptx_dp_phy *cdns_phy)
> +{
> +	u32 val;
> +
> +	val = cdns_phy_reg_read(cdns_phy, PHY_PMA_CMN_CTRL1);
> +	val &= 0xff8f;
> +	/*
> +	 * single ended reference clock (val |= 0x0030);
> +	 * differential clock  (val |= 0x0000);
> +	 *
> +	 * for differential clock on the refclk_p and
> +	 * refclk_m off chip pins: CMN_DIAG_ACYA[8]=1'b1
> +	 * cdns_phy_reg_write(cdns_phy, CMN_DIAG_ACYA, 0x0100);
> +	 */
> +	val |= 0x0030;
> +	cdns_phy_reg_write(cdns_phy, PHY_PMA_CMN_CTRL1, val);
> +}
> +
> +static int hdptx_dp_phy_power_up(struct cdns_hdptx_dp_phy *cdns_phy)
> +{
> +	u32 val, i;
> +
> +	/* Enable HDP PLL’s for high speed clocks */
> +	val = cdns_phy_reg_read(cdns_phy, PHY_HDP_CLK_CTL);
> +	val |= (1 << 0);
> +	cdns_phy_reg_write(cdns_phy, PHY_HDP_CLK_CTL, val);
> +	/* Wait for PLL ready ACK */
> +	for (i = 0; i < 10; i++) {
> +		val = cdns_phy_reg_read(cdns_phy, PHY_HDP_CLK_CTL);
> +		if (val & (1 << 1))
> +			break;
> +		msleep(20);
> +	}
> +	if (i == 10) {
> +		dev_err(cdns_phy->dev, "Wait PLL Ack failed\n");
> +		return -1;
> +	}
> +
> +	/* Enable HDP PLL’s data rate and full rate clocks out of PMA. */
> +	val = cdns_phy_reg_read(cdns_phy, PHY_HDP_CLK_CTL);
> +	val |= (1 << 2);
> +	cdns_phy_reg_write(cdns_phy, PHY_HDP_CLK_CTL, val);
> +	/* Wait for PLL clock enable ACK */
> +	for (i = 0; i < 10; i++) {
> +		val = cdns_phy_reg_read(cdns_phy, PHY_HDP_CLK_CTL);
> +		if (val & (1 << 3))
> +			break;
> +		msleep(20);
> +	}
> +	if (i == 10) {
> +		dev_err(cdns_phy->dev, "Wait PLL clock enable ACk failed\n");
> +		return -1;
> +	}
> +
> +	/* Configure PHY in A2 Mode */
> +	cdns_phy_reg_write(cdns_phy, PHY_HDP_MODE_CTRL, 0x0004);
> +	/* Wait for Power State A2 Ack */
> +	for (i = 0; i < 10; i++) {
> +		val = cdns_phy_reg_read(cdns_phy, PHY_HDP_MODE_CTRL);
> +		if (val & (1 << 6))
> +			break;
> +		msleep(20);
> +	}
> +	if (i == 10) {
> +		dev_err(cdns_phy->dev, "Wait A2 Ack failed\n");
> +		return -1;
> +	}
> +
> +	/* Configure PHY in A0 mode (PHY must be in the A0 power
> +	 * state in order to transmit data)
> +	 */
> +	cdns_phy_reg_write(cdns_phy, PHY_HDP_MODE_CTRL, 0x0101);
> +
> +	/* Wait for Power State A0 Ack */
> +	for (i = 0; i < 10; i++) {
> +		val = cdns_phy_reg_read(cdns_phy, PHY_HDP_MODE_CTRL);
> +		if (val & (1 << 4))
> +			break;
> +		msleep(20);
> +	}
> +	if (i == 10) {
> +		dev_err(cdns_phy->dev, "Wait A0 Ack failed\n");
> +		return -1;
> +	}
> +
> +	cdns_phy->power_up = true;
> +
> +	return 0;
> +}
> +
> +static void hdptx_dp_phy_power_down(struct cdns_hdptx_dp_phy *cdns_phy)
> +{
> +	u16 val;
> +	int i;
> +
> +	if (!cdns_phy->power_up)
> +		return;
> +
> +	/* Place the PHY lanes in the A3 power state. */
> +	cdns_phy_reg_write(cdns_phy, PHY_HDP_MODE_CTRL, 0x8);
> +	/* Wait for Power State A3 Ack */
> +	for (i = 0; i < 10; i++) {
> +		val = cdns_phy_reg_read(cdns_phy, PHY_HDP_MODE_CTRL);
> +		if (val & (1 << 7))
> +			break;
> +		msleep(20);
> +	}
> +	if (i == 10) {
> +		dev_err(cdns_phy->dev, "Wait A3 Ack failed\n");
> +		return;
> +	}
> +
> +	/* Disable HDP PLL’s data rate and full rate clocks out of PMA. */
> +	val = cdns_phy_reg_read(cdns_phy, PHY_HDP_CLK_CTL);
> +	val &= ~(1 << 2);
> +	cdns_phy_reg_write(cdns_phy, PHY_HDP_CLK_CTL, val);
> +	/* Wait for PLL clock gate ACK */
> +	for (i = 0; i < 10; i++) {
> +		val = cdns_phy_reg_read(cdns_phy, PHY_HDP_CLK_CTL);
> +		if (!(val & (1 << 3)))
> +			break;
> +		msleep(20);
> +	}
> +	if (i == 10) {
> +		dev_err(cdns_phy->dev, "Wait PLL clock gate Ack failed\n");
> +		return;
> +	}
> +
> +	/* Disable HDP PLL’s for high speed clocks */
> +	val = cdns_phy_reg_read(cdns_phy, PHY_HDP_CLK_CTL);
> +	val &= ~(1 << 0);
> +	cdns_phy_reg_write(cdns_phy, PHY_HDP_CLK_CTL, val);
> +	/* Wait for PLL disable ACK */
> +	for (i = 0; i < 10; i++) {
> +		val = cdns_phy_reg_read(cdns_phy, PHY_HDP_CLK_CTL);
> +		if (!(val & (1 << 1)))
> +			break;
> +		msleep(20);
> +	}
> +	if (i == 10) {
> +		dev_err(cdns_phy->dev, "Wait PLL disable Ack failed\n");
> +		return;
> +	}
> +}
> +
> +static int cdns_hdptx_dp_phy_on(struct phy *phy)
> +{
> +	struct cdns_hdptx_dp_phy *cdns_phy = phy_get_drvdata(phy);
> +
> +	return hdptx_dp_phy_power_up(cdns_phy);
> +}
> +
> +static int cdns_hdptx_dp_phy_off(struct phy *phy)
> +{
> +	struct cdns_hdptx_dp_phy *cdns_phy = phy_get_drvdata(phy);
> +
> +	hdptx_dp_phy_power_down(cdns_phy);
> +
> +	return 0;
> +}
> +
> +static int cdns_hdptx_dp_phy_init(struct phy *phy)
> +{
> +	struct cdns_hdptx_dp_phy *cdns_phy = phy_get_drvdata(phy);
> +	int ret;
> +
> +	hdptx_dp_phy_ref_clock_type(cdns_phy);
> +
> +	/* PHY power up */
> +	ret = hdptx_dp_phy_power_up(cdns_phy);
> +	if (ret < 0)
> +		return ret;
> +
> +	hdptx_dp_aux_cfg(cdns_phy);
> +
> +	return ret;
> +}
> +
> +static int cdns_hdptx_dp_configure(struct phy *phy,
> +				   union phy_configure_opts *opts)
> +{
> +	struct cdns_hdptx_dp_phy *cdns_phy = phy_get_drvdata(phy);
> +	int ret;
> +
> +	cdns_phy->link_rate = opts->dp.link_rate;
> +	cdns_phy->num_lanes = opts->dp.lanes;
> +
> +	if (cdns_phy->link_rate > MAX_LINK_RATE) {
> +		dev_err(cdns_phy->dev, "Link Rate(%d) Not supported\n", cdns_phy->link_rate);
> +		return false;
> +	}
> +
> +	/* Disable phy clock if PHY in power up state */
> +	hdptx_dp_phy_power_down(cdns_phy);
> +
> +	if (cdns_phy->ref_clk_rate == REF_CLK_27MHZ) {
> +		hdptx_dp_phy_pma_cmn_cfg_27mhz(cdns_phy);
> +		hdptx_dp_phy_pma_cmn_pll0_27mhz(cdns_phy);
> +	} else {
> +		dev_err(cdns_phy->dev, "Not support ref clock rate\n");
> +	}
> +
> +	/* PHY power up */
> +	ret = hdptx_dp_phy_power_up(cdns_phy);
> +
> +	return ret;
> +}
> +
> +static const struct phy_ops cdns_hdptx_dp_phy_ops = {
> +	.init = cdns_hdptx_dp_phy_init,
> +	.configure = cdns_hdptx_dp_configure,
> +	.power_on = cdns_hdptx_dp_phy_on,
> +	.power_off = cdns_hdptx_dp_phy_off,
> +	.owner = THIS_MODULE,
> +};
> +
> +static int cdns_hdptx_dp_phy_probe(struct platform_device *pdev)
> +{
> +	struct cdns_hdptx_dp_phy *cdns_phy;
> +	struct device *dev = &pdev->dev;
> +	struct device_node *node = dev->of_node;
> +	struct phy_provider *phy_provider;
> +	struct resource *res;
> +	struct phy *phy;
> +	int ret;
> +
> +	cdns_phy = devm_kzalloc(dev, sizeof(*cdns_phy), GFP_KERNEL);
> +	if (!cdns_phy)
> +		return -ENOMEM;
> +
> +	dev_set_drvdata(dev, cdns_phy);
> +	cdns_phy->dev = dev;
> +	mutex_init(&cdns_phy->mbox_mutex);
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	if (!res)
> +		return -ENODEV;
> +	cdns_phy->regs = devm_ioremap(dev, res->start, resource_size(res));
> +	if (IS_ERR(cdns_phy->regs))
> +		return PTR_ERR(cdns_phy->regs);
> +
> +	phy = devm_phy_create(dev, node, &cdns_hdptx_dp_phy_ops);
> +	if (IS_ERR(phy))
> +		return PTR_ERR(phy);
> +
> +	phy->attrs.mode = PHY_MODE_DP;
> +	cdns_phy->phy = phy;
> +	phy_set_drvdata(phy, cdns_phy);
> +
> +	ret = hdptx_dp_clk_enable(cdns_phy);
> +	if (ret) {
> +		dev_err(dev, "Init clk fail\n");
> +		return -EINVAL;
> +	}
> +
> +	phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
> +	if (IS_ERR(phy_provider)) {
> +		ret = PTR_ERR(phy_provider);
> +		goto clk_disable;
> +	}
> +
> +	return 0;
> +
> +clk_disable:
> +	hdptx_dp_clk_disable(cdns_phy);
> +
> +	return -EINVAL;
> +}
> +
> +static int cdns_hdptx_dp_phy_remove(struct platform_device *pdev)
> +{
> +	struct cdns_hdptx_dp_phy *cdns_phy = platform_get_drvdata(pdev);
> +
> +	hdptx_dp_clk_disable(cdns_phy);
> +
> +	return 0;
> +}
> +
> +static const struct of_device_id cdns_hdptx_dp_phy_of_match[] = {
> +	{.compatible = "fsl,imx8mq-dp-phy" },
> +	{ /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, cdns_hdptx_dp_phy_of_match);
> +
> +static struct platform_driver cdns_hdptx_dp_phy_driver = {
> +	.probe = cdns_hdptx_dp_phy_probe,
> +	.remove = cdns_hdptx_dp_phy_remove,
> +	.driver = {
> +		.name	= "cdns-hdptx-dp-phy",
> +		.of_match_table	= cdns_hdptx_dp_phy_of_match,
> +	}
> +};
> +module_platform_driver(cdns_hdptx_dp_phy_driver);
> +
> +MODULE_AUTHOR("Sandor Yu <sandor.yu@nxp.com>");
> +MODULE_DESCRIPTION("Cadence HDP-TX DisplayPort PHY driver");
> +MODULE_LICENSE("GPL");
> -- 
> 2.34.1

-- 
~Vinod