Re: [PATCH v4 10/13] media: imx8mq-mipi-csi2: Add support for i.MX8QXP

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Frank,

Thank you for the patch.

On Tue, Apr 08, 2025 at 05:53:08PM -0400, Frank Li wrote:
> Add support for i.MX8QXP, which has a dedicated control and status register
> (CSR) space. Enable obtaining the second register space and initializing
> PHY and link settings accordingly.
> 
> Signed-off-by: Frank Li <Frank.Li@nxp.com>
> ---
> change from v3 to v4
> - remove reset_delay
> - sort register field defination
> - fix error messag in dev_err_probe
> - fix comments
> - use true for 1
> - regmap_clear_bits(state->phy_gpr, CSI2SS_CTRL_CLK_RESET, CSI2SS_CTRL_CLK_RESET_EN);
> in imx8qxp_gpr_disable()
> - use regmap_write to clean register at imx8qxp_gpr_enable()
> - remove reduntant CSI2SS_PLM_CTRL_POLARITY
> - rename register DATA_TYPE to DATA_TYPE_DISABLE_BF
> 
> change from v2 to v3
> - use dedicate csr reg to control phy and link settings.
> 
> Change from v1 to v2
> - change 8QM go 8QXP, 8QM will failback to 8QXP to keep consisense with
> phy drivers
> ---
>  drivers/media/platform/nxp/imx8mq-mipi-csi2.c | 111 ++++++++++++++++++++++++++
>  1 file changed, 111 insertions(+)
> 
> diff --git a/drivers/media/platform/nxp/imx8mq-mipi-csi2.c b/drivers/media/platform/nxp/imx8mq-mipi-csi2.c
> index 59ec7107b4508..c6eb6dd0d9e5a 100644
> --- a/drivers/media/platform/nxp/imx8mq-mipi-csi2.c
> +++ b/drivers/media/platform/nxp/imx8mq-mipi-csi2.c
> @@ -5,6 +5,7 @@
>   * Copyright (C) 2021 Purism SPC
>   */
>  
> +#include <linux/bitfield.h>
>  #include <linux/clk.h>
>  #include <linux/clk-provider.h>
>  #include <linux/delay.h>
> @@ -88,6 +89,7 @@ static const char * const imx8mq_mipi_csi_clk_id[CSI2_NUM_CLKS] = {
>  struct imx8mq_plat_data {
>  	int (*enable)(struct csi_state *state, u32 hs_settle);
>  	void (*disable)(struct csi_state *state);
> +	bool use_reg_csr;
>  };
>  
>  /*
> @@ -167,6 +169,95 @@ static const struct imx8mq_plat_data imx8mq_data = {
>  	.enable = imx8mq_gpr_enable,
>  };
>  
> +/* -----------------------------------------------------------------------------
> + * i.MX8QXP
> + */
> +
> +#define CSI2SS_PL_CLK_INTERVAL_US		100
> +#define CSI2SS_PL_CLK_TIMEOUT_US		100000
> +
> +#define CSI2SS_PLM_CTRL				0x0
> +#define CSI2SS_PLM_CTRL_ENABLE_PL		BIT(0)
> +#define CSI2SS_PLM_CTRL_VSYNC_OVERRIDE		BIT(9)
> +#define CSI2SS_PLM_CTRL_HSYNC_OVERRIDE		BIT(10)
> +#define CSI2SS_PLM_CTRL_VALID_OVERRIDE		BIT(11)
> +#define CSI2SS_PLM_CTRL_POLARITY_HIGH		BIT(12)
> +#define CSI2SS_PLM_CTRL_PL_CLK_RUN		BIT(31)
> +
> +#define CSI2SS_PHY_CTRL				0x4
> +#define CSI2SS_PHY_CTRL_RX_ENABLE		BIT(0)
> +#define CSI2SS_PHY_CTRL_AUTO_PD_EN		BIT(1)
> +#define CSI2SS_PHY_CTRL_DDRCLK_EN		BIT(2)
> +#define CSI2SS_PHY_CTRL_CONT_CLK_MODE		BIT(3)
> +#define CSI2SS_PHY_CTRL_RX_HS_SETTLE_MASK	GENMASK(9, 4)
> +#define CSI2SS_PHY_CTRL_RTERM_SEL		BIT(21)
> +#define CSI2SS_PHY_CTRL_PD			BIT(22)
> +
> +#define CSI2SS_DATA_TYPE_DISABLE_BF		0x38
> +#define CSI2SS_DATA_TYPE_DISABLE_BF_MASK	GENMASK(23, 0)
> +
> +#define CSI2SS_CTRL_CLK_RESET			0x44
> +#define CSI2SS_CTRL_CLK_RESET_EN		BIT(0)
> +
> +static int imx8qxp_gpr_enable(struct csi_state *state, u32 hs_settle)
> +{
> +	int ret;
> +	u32 val;
> +
> +	/* Clear format */
> +	regmap_clear_bits(state->phy_gpr,
> +			  CSI2SS_DATA_TYPE_DISABLE_BF, CSI2SS_DATA_TYPE_DISABLE_BF_MASK);

	regmap_clear_bits(state->phy_gpr, CSI2SS_DATA_TYPE_DISABLE_BF,
			  CSI2SS_DATA_TYPE_DISABLE_BF_MASK);

> +
> +	regmap_write(state->phy_gpr, CSI2SS_PLM_CTRL, 0x0);
> +	regmap_write(state->phy_gpr, CSI2SS_PHY_CTRL, 0x0);

This write to CSI2SS_PHY_CTRL is overridden by the next line. Is it
needed ?

> +
> +	regmap_write(state->phy_gpr, CSI2SS_PHY_CTRL,
> +		     FIELD_PREP(CSI2SS_PHY_CTRL_RX_HS_SETTLE_MASK, hs_settle) |
> +		     CSI2SS_PHY_CTRL_RX_ENABLE | CSI2SS_PHY_CTRL_DDRCLK_EN |
> +		     CSI2SS_PHY_CTRL_CONT_CLK_MODE | CSI2SS_PHY_CTRL_PD |
> +		     CSI2SS_PHY_CTRL_RTERM_SEL | CSI2SS_PHY_CTRL_AUTO_PD_EN);
> +
> +	ret = regmap_read_poll_timeout(state->phy_gpr, CSI2SS_PLM_CTRL,
> +				       val, !(val & CSI2SS_PLM_CTRL_PL_CLK_RUN),
> +				       CSI2SS_PL_CLK_INTERVAL_US,
> +				       CSI2SS_PL_CLK_TIMEOUT_US);
> +
> +	if (ret) {
> +		dev_err(state->dev, "Timeout waiting for Pixel-Link clock");

Missing \n at end of string.

> +		return ret;
> +	}
> +
> +	/* Enable Pixel link Master */
> +	regmap_set_bits(state->phy_gpr, CSI2SS_PLM_CTRL,
> +			CSI2SS_PLM_CTRL_ENABLE_PL | CSI2SS_PLM_CTRL_VALID_OVERRIDE);
> +
> +	/* PHY Enable */
> +	regmap_clear_bits(state->phy_gpr, CSI2SS_PHY_CTRL,
> +			  CSI2SS_PHY_CTRL_PD | CSI2SS_PLM_CTRL_POLARITY_HIGH);
> +
> +	/* Release Reset */
> +	regmap_set_bits(state->phy_gpr, CSI2SS_CTRL_CLK_RESET, CSI2SS_CTRL_CLK_RESET_EN);
> +
> +	return ret;
> +}
> +
> +static void imx8qxp_gpr_disable(struct csi_state *state)
> +{
> +	/* Disable Pixel Link */
> +	regmap_write(state->phy_gpr, CSI2SS_PLM_CTRL, 0x0);
> +
> +	/* Disable PHY */
> +	regmap_write(state->phy_gpr, CSI2SS_PHY_CTRL, 0x0);
> +
> +	regmap_clear_bits(state->phy_gpr, CSI2SS_CTRL_CLK_RESET, CSI2SS_CTRL_CLK_RESET_EN);

	regmap_clear_bits(state->phy_gpr, CSI2SS_CTRL_CLK_RESET,
			  CSI2SS_CTRL_CLK_RESET_EN);

With those small issues addressed,

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

> +};
> +
> +static const struct imx8mq_plat_data imx8qxp_data = {
> +	.enable = imx8qxp_gpr_enable,
> +	.disable = imx8qxp_gpr_disable,
> +	.use_reg_csr = true,
> +};
> +
>  static const struct csi2_pix_format imx8mq_mipi_csi_formats[] = {
>  	/* RAW (Bayer and greyscale) formats. */
>  	{
> @@ -865,6 +956,25 @@ static int imx8mq_mipi_csi_parse_dt(struct csi_state *state)
>  		return PTR_ERR(state->rst);
>  	}
>  
> +	if (state->pdata->use_reg_csr) {
> +		const struct regmap_config regmap_config = {
> +			.reg_bits = 32,
> +			.val_bits = 32,
> +			.reg_stride = 4,
> +		};
> +		void __iomem *base;
> +
> +		base = devm_platform_ioremap_resource(to_platform_device(dev), 1);
> +		if (IS_ERR(base))
> +			return dev_err_probe(dev, IS_ERR(base), "Missing CSR register\n");
> +
> +		state->phy_gpr = devm_regmap_init_mmio(dev, base, &regmap_config);
> +		if (IS_ERR(state->phy_gpr))
> +			return dev_err_probe(dev, PTR_ERR(state->phy_gpr),
> +					     "Failed to init CSI MMIO regmap\n");
> +		return 0;
> +	}
> +
>  	ret = of_property_read_u32_array(np, "fsl,mipi-phy-gpr", out_val,
>  					 ARRAY_SIZE(out_val));
>  	if (ret) {
> @@ -984,6 +1094,7 @@ static void imx8mq_mipi_csi_remove(struct platform_device *pdev)
>  
>  static const struct of_device_id imx8mq_mipi_csi_of_match[] = {
>  	{ .compatible = "fsl,imx8mq-mipi-csi2", .data = &imx8mq_data },
> +	{ .compatible = "fsl,imx8qxp-mipi-csi2", .data = &imx8qxp_data },
>  	{ /* sentinel */ },
>  };
>  MODULE_DEVICE_TABLE(of, imx8mq_mipi_csi_of_match);

-- 
Regards,

Laurent Pinchart