Re: [PATCH 16/39] drm/imx: dc: lb: Pass struct dc_lb_subdev_match_data via OF match data

[Frank Li <Frank.li@nxp.com>]

On Sat, Oct 11, 2025 at 06:51:31PM +0200, Marek Vasut wrote:
> Introduce struct dc_lb_subdev_match_data which describes the differences
> between i.MX8QXP and i.MX95, which in this case link ID mapping as well
> as address space offsets, and pass it as OF match data into the driver, so
> the driver can use the match data to correctly select pixel data routing.
> This is a preparatory patch for i.MX95 addition. No functional change.
>
> Signed-off-by: Marek Vasut <marek.vasut@mailbox.org>
> ---
> Cc: Abel Vesa <abelvesa@kernel.org>
> Cc: Conor Dooley <conor+dt@kernel.org>
> Cc: Fabio Estevam <festevam@gmail.com>
> Cc: Krzysztof Kozlowski <krzk+dt@kernel.org>
> Cc: Laurent Pinchart <Laurent.pinchart@ideasonboard.com>
> Cc: Liu Ying <victor.liu@nxp.com>
> Cc: Lucas Stach <l.stach@pengutronix.de>
> Cc: Peng Fan <peng.fan@nxp.com>
> Cc: Pengutronix Kernel Team <kernel@pengutronix.de>
> Cc: Rob Herring <robh@kernel.org>
> Cc: Shawn Guo <shawnguo@kernel.org>
> Cc: Thomas Zimmermann <tzimmermann@suse.de>
> Cc: devicetree@vger.kernel.org
> Cc: dri-devel@lists.freedesktop.org
> Cc: imx@lists.linux.dev
> Cc: linux-arm-kernel@lists.infradead.org
> Cc: linux-clk@vger.kernel.org
> ---
>  drivers/gpu/drm/imx/dc/dc-lb.c | 42 ++++++++++++++++++++++++++--------
>  drivers/gpu/drm/imx/dc/dc-pe.h |  3 +++
>  2 files changed, 35 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/gpu/drm/imx/dc/dc-lb.c b/drivers/gpu/drm/imx/dc/dc-lb.c
> index 619353456743c..ba9183b244ab3 100644
> --- a/drivers/gpu/drm/imx/dc/dc-lb.c
> +++ b/drivers/gpu/drm/imx/dc/dc-lb.c
> @@ -56,6 +56,14 @@
>  #define  YPOS_MASK				GENMASK(31, 16)
>  #define  YPOS(x)				FIELD_PREP(YPOS_MASK, (x))
>
> +struct dc_lb_subdev_match_data {
> +	const enum dc_link_id		*pri_sels;
> +	const enum dc_link_id		*sec_sels;
> +	const enum dc_link_id		first_lb;
> +	unsigned int			last_cf;
> +	const struct dc_subdev_info	*info;
> +};
> +
>  enum dc_lb_blend_func {
>  	DC_LAYERBLEND_BLEND_ZERO,
>  	DC_LAYERBLEND_BLEND_ONE,
> @@ -119,7 +127,7 @@ static const struct regmap_config dc_lb_cfg_regmap_config = {
>  	.max_register = POSITION,
>  };
>
> -static const enum dc_link_id prim_sels[] = {
> +static const enum dc_link_id prim_sels_imx8qxp[] = {
>  	/* common options */
>  	LINK_ID_NONE,
>  	LINK_ID_CONSTFRAME0,
> @@ -137,12 +145,22 @@ static const enum dc_link_id prim_sels[] = {
>  	LINK_ID_LAYERBLEND1_MX8QXP,
>  	LINK_ID_LAYERBLEND2_MX8QXP,
>  	LINK_ID_LAYERBLEND3_MX8QXP,
> +	LINK_ID_LAST
>  };
>
> -static const enum dc_link_id sec_sels[] = {
> +static const enum dc_link_id sec_sels_imx8qxp[] = {
>  	LINK_ID_NONE,
>  	LINK_ID_FETCHWARP2,
>  	LINK_ID_FETCHLAYER0,
> +	LINK_ID_LAST
> +};
> +
> +static const struct dc_lb_subdev_match_data dc_lb_match_data_imx8qxp = {
> +	.pri_sels = prim_sels_imx8qxp,
> +	.sec_sels = sec_sels_imx8qxp,
> +	.first_lb = LINK_ID_LAYERBLEND0_MX8QXP,
> +	.last_cf = 5,
> +	.info = dc_lb_info_imx8qxp,
>  };
>
>  enum dc_link_id dc_lb_get_link_id(struct dc_lb *lb)
> @@ -152,11 +170,10 @@ enum dc_link_id dc_lb_get_link_id(struct dc_lb *lb)
>
>  void dc_lb_pec_dynamic_prim_sel(struct dc_lb *lb, enum dc_link_id prim)
>  {
> -	int fixed_sels_num = ARRAY_SIZE(prim_sels) - 4;
>  	int i;
>
> -	for (i = 0; i < fixed_sels_num + lb->id; i++) {
> -		if (prim_sels[i] == prim) {
> +	for (i = 0; i < lb->last_cf + lb->id; i++) {
> +		if (lb->pri_sels[i] == prim) {
>  			regmap_write_bits(lb->reg_pec, PIXENGCFG_DYNAMIC,
>  					  PIXENGCFG_DYNAMIC_PRIM_SEL_MASK,
>  					  PIXENGCFG_DYNAMIC_PRIM_SEL(prim));
> @@ -169,10 +186,10 @@ void dc_lb_pec_dynamic_prim_sel(struct dc_lb *lb, enum dc_link_id prim)
>
>  void dc_lb_pec_dynamic_sec_sel(struct dc_lb *lb, enum dc_link_id sec)
>  {
> -	int i;
> +	int i = 0;
>
> -	for (i = 0; i < ARRAY_SIZE(sec_sels); i++) {
> -		if (sec_sels[i] == sec) {
> +	while (lb->sec_sels[i] != LINK_ID_LAST) {
> +		if (lb->sec_sels[i++] == sec) {
>  			regmap_write_bits(lb->reg_pec, PIXENGCFG_DYNAMIC,
>  					  PIXENGCFG_DYNAMIC_SEC_SEL_MASK,
>  					  PIXENGCFG_DYNAMIC_SEC_SEL(sec));
> @@ -245,6 +262,8 @@ void dc_lb_init(struct dc_lb *lb)
>
>  static int dc_lb_bind(struct device *dev, struct device *master, void *data)
>  {
> +	const struct dc_lb_subdev_match_data *dc_lb_match_data = device_get_match_data(dev);
> +	const struct dc_subdev_info *dc_lb_info = dc_lb_match_data->info;
>  	struct platform_device *pdev = to_platform_device(dev);
>  	struct dc_drm_device *dc_drm = data;
>  	struct resource *res_pec;
> @@ -281,7 +300,10 @@ static int dc_lb_bind(struct device *dev, struct device *master, void *data)
>  	}
>
>  	lb->dev = dev;
> -	lb->link = LINK_ID_LAYERBLEND0_MX8QXP + lb->id;
> +	lb->link = dc_lb_match_data->first_lb + lb->id;
> +	lb->pri_sels = dc_lb_match_data->pri_sels;
> +	lb->sec_sels = dc_lb_match_data->sec_sels;
> +	lb->last_cf = dc_lb_match_data->last_cf;
>
>  	dc_drm->lb[lb->id] = lb;
>
> @@ -310,7 +332,7 @@ static void dc_lb_remove(struct platform_device *pdev)
>  }
>
>  static const struct of_device_id dc_lb_dt_ids[] = {
> -	{ .compatible = "fsl,imx8qxp-dc-layerblend" },
> +	{ .compatible = "fsl,imx8qxp-dc-layerblend", .data = &dc_lb_match_data_imx8qxp },
>  	{ /* sentinel */ }
>  };
>  MODULE_DEVICE_TABLE(of, dc_lb_dt_ids);
> diff --git a/drivers/gpu/drm/imx/dc/dc-pe.h b/drivers/gpu/drm/imx/dc/dc-pe.h
> index 7928f947b0cef..492d193127bc1 100644
> --- a/drivers/gpu/drm/imx/dc/dc-pe.h
> +++ b/drivers/gpu/drm/imx/dc/dc-pe.h
> @@ -65,6 +65,9 @@ struct dc_lb {
>  	struct regmap *reg_cfg;
>  	int id;
>  	enum dc_link_id link;
> +	const enum dc_link_id *pri_sels;
> +	const enum dc_link_id *sec_sels;
> +	unsigned int last_cf;

Direct use pointer to dc_lb_subdev_match_data to avoid copy data to here.

Frank
>  };
>
>  struct dc_pe {
> --
> 2.51.0
>