[0/2] Add DSS support for TI AM62A7 SoC

This patch series adds a new compatible for the Display SubSystem (DSS)
controller on TI's AM62A7 SoC. It further adds the required support, for
the same, in the tidss driver.

The DSS controller is similar to the recently added AM625 DSS, with the
key difference being the absence of VP1 output on the SoC. The VP1 in
AM62A7 DSS is tied off and cannot be used, unlike in AM625, where the
VP1 was connected to 2 OLDI TXes. The video pipeline that corresponds to
VP1 still exists and can be used to overlay planes on the VP2's primary
plane. This can be done using the overlay managers inside the SoC.
Moreover, DSS VP2 can output Full-HD RGB888 DPI video signals.

I have tested these patches on AM62A7 SK-EVM, which converts DPI signals
to HDMI on the platform using the Sil9022A HDMI transmitter. All the
patches, required to enable display on AM62A7-SK, can be found on my
github fork[0] in the branch "next_am62a".

Regards
Aradhya

[0]: https://github.com/aradhya07/linux-ab/tree/next_am62a


Aradhya Bhatia (2):
  dt-bindings: display: ti: Add support for am62a7 dss
  drivers/tidss: Add support for AM62A7 DSS

 .../bindings/display/ti/ti,am65x-dss.yaml     | 14 +++++
 drivers/gpu/drm/tidss/tidss_dispc.c           | 53 +++++++++++++++++++
 drivers/gpu/drm/tidss/tidss_dispc.h           |  2 +
 drivers/gpu/drm/tidss/tidss_drv.c             |  1 +
 4 files changed, 70 insertions(+)


base-commit: 47762f08697484cf0c2f2904b8c52375ed26c8cb

On 18-Aug-23 18:47, Aradhya Bhatia wrote:
> Add support for the DSS controller on TI's AM62A7 SoC in the tidss
> driver.
> 
> This contrller has 2 video pipelines that can render 2 video planes on
> over a screen, using the overlay managers. The output of the DSS comes
> from video port 2 (VP2) in the form of RGB88 DPI signals, while the VP1
> is tied off inside the SoC.
> 
> Signed-off-by: Aradhya Bhatia <a-bhatia1@ti.com>
> ---
>  drivers/gpu/drm/tidss/tidss_dispc.c | 53 +++++++++++++++++++++++++++++
>  drivers/gpu/drm/tidss/tidss_dispc.h |  2 ++
>  drivers/gpu/drm/tidss/tidss_drv.c   |  1 +
>  3 files changed, 56 insertions(+)
> 
> diff --git a/drivers/gpu/drm/tidss/tidss_dispc.c b/drivers/gpu/drm/tidss/tidss_dispc.c
> index 9d9dee7abaef..0e2d55d9a0d7 100644
> --- a/drivers/gpu/drm/tidss/tidss_dispc.c
> +++ b/drivers/gpu/drm/tidss/tidss_dispc.c
> @@ -322,6 +322,54 @@ const struct dispc_features dispc_am625_feats = {
>  	.vid_order = { 1, 0 },
>  };
>  
> +const struct dispc_features dispc_am62a7_feats = {
> +	.max_pclk_khz = {
> +		[DISPC_VP_DPI] = 165000,
> +	},
> +
> +	.scaling = {
> +		.in_width_max_5tap_rgb = 1280,
> +		.in_width_max_3tap_rgb = 2560,
> +		.in_width_max_5tap_yuv = 2560,
> +		.in_width_max_3tap_yuv = 4096,
> +		.upscale_limit = 16,
> +		.downscale_limit_5tap = 4,
> +		.downscale_limit_3tap = 2,
> +		/*
> +		 * The max supported pixel inc value is 255. The value
> +		 * of pixel inc is calculated like this: 1+(xinc-1)*bpp.
> +		 * The maximum bpp of all formats supported by the HW
> +		 * is 8. So the maximum supported xinc value is 32,
> +		 * because 1+(32-1)*8 < 255 < 1+(33-1)*4.
> +		 */
> +		.xinc_max = 32,
> +	},
> +
> +	.subrev = DISPC_AM62A7,
> +
> +	.common = "common",
> +	.common_regs = tidss_am65x_common_regs,
> +
> +	.num_vps = 2,
> +	.vp_name = { "vp1", "vp2" },
> +	.ovr_name = { "ovr1", "ovr2" },
> +	.vpclk_name =  { "vp1", "vp2" },
> +	.vp_bus_type = { DISPC_VP_INTERNAL, DISPC_VP_DPI },
> +
> +	.vp_feat = { .color = {
> +			.has_ctm = true,
> +			.gamma_size = 256,
> +			.gamma_type = TIDSS_GAMMA_8BIT,
> +		},
> +	},
> +
> +	.num_planes = 2,
> +	/* note: vid is plane_id 0 and vidl1 is plane_id 1 */
> +	.vid_name = { "vid", "vidl1" },
> +	.vid_lite = { false, true, },
> +	.vid_order = { 1, 0 },
> +};
> +
>  static const u16 *dispc_common_regmap;
>  
>  struct dss_vp_data {
> @@ -823,6 +871,7 @@ dispc_irq_t dispc_read_and_clear_irqstatus(struct dispc_device *dispc)
>  	switch (dispc->feat->subrev) {
>  	case DISPC_K2G:
>  		return dispc_k2g_read_and_clear_irqstatus(dispc);
> +	case DISPC_AM62A7:
>  	case DISPC_AM625:
>  	case DISPC_AM65X:
>  	case DISPC_J721E:
> @@ -839,6 +888,7 @@ void dispc_set_irqenable(struct dispc_device *dispc, dispc_irq_t mask)
>  	case DISPC_K2G:
>  		dispc_k2g_set_irqenable(dispc, mask);
>  		break;
> +	case DISPC_AM62A7:
>  	case DISPC_AM625:
>  	case DISPC_AM65X:
>  	case DISPC_J721E:
> @@ -1330,6 +1380,7 @@ void dispc_ovr_set_plane(struct dispc_device *dispc, u32 hw_plane,
>  		dispc_k2g_ovr_set_plane(dispc, hw_plane, hw_videoport,
>  					x, y, layer);
>  		break;
> +	case DISPC_AM62A7:
>  	case DISPC_AM625:
>  	case DISPC_AM65X:
>  		dispc_am65x_ovr_set_plane(dispc, hw_plane, hw_videoport,
> @@ -2249,6 +2300,7 @@ static void dispc_plane_init(struct dispc_device *dispc)
>  	case DISPC_K2G:
>  		dispc_k2g_plane_init(dispc);
>  		break;
> +	case DISPC_AM62A7:
>  	case DISPC_AM625:
>  	case DISPC_AM65X:
>  	case DISPC_J721E:
> @@ -2356,6 +2408,7 @@ static void dispc_vp_write_gamma_table(struct dispc_device *dispc,
>  	case DISPC_K2G:
>  		dispc_k2g_vp_write_gamma_table(dispc, hw_videoport);
>  		break;
> +	case DISPC_AM62A7:
>  	case DISPC_AM625:
>  	case DISPC_AM65X:
>  		dispc_am65x_vp_write_gamma_table(dispc, hw_videoport);
> diff --git a/drivers/gpu/drm/tidss/tidss_dispc.h b/drivers/gpu/drm/tidss/tidss_dispc.h
> index 33ac5ad7a423..2aa1c814ea2a 100644
> --- a/drivers/gpu/drm/tidss/tidss_dispc.h
> +++ b/drivers/gpu/drm/tidss/tidss_dispc.h
> @@ -59,6 +59,7 @@ enum dispc_vp_bus_type {
>  
>  enum dispc_dss_subrevision {
>  	DISPC_K2G,
> +	DISPC_AM62A7,
>  	DISPC_AM625,
>  	DISPC_AM65X,
>  	DISPC_J721E,
> @@ -88,6 +89,7 @@ struct dispc_features {

Made an oopsie and missed sorting 'DISPC_AM62A7' in above instances. It
should be under DISPC_AM625. Please ignore this patch / series. Will
send a v2. Apologies for the noise.

Regards
Aradhya

>  
>  extern const struct dispc_features dispc_k2g_feats;
>  extern const struct dispc_features dispc_am625_feats;
> +extern const struct dispc_features dispc_am62a7_feats;
>  extern const struct dispc_features dispc_am65x_feats;
>  extern const struct dispc_features dispc_j721e_feats;
>  
> diff --git a/drivers/gpu/drm/tidss/tidss_drv.c b/drivers/gpu/drm/tidss/tidss_drv.c
> index 4d063eb9cd0b..edf69d020544 100644
> --- a/drivers/gpu/drm/tidss/tidss_drv.c
> +++ b/drivers/gpu/drm/tidss/tidss_drv.c
> @@ -231,6 +231,7 @@ static void tidss_shutdown(struct platform_device *pdev)
>  static const struct of_device_id tidss_of_table[] = {
>  	{ .compatible = "ti,k2g-dss", .data = &dispc_k2g_feats, },
>  	{ .compatible = "ti,am625-dss", .data = &dispc_am625_feats, },
> +	{ .compatible = "ti,am62a7-dss", .data = &dispc_am62a7_feats, },
>  	{ .compatible = "ti,am65x-dss", .data = &dispc_am65x_feats, },
>  	{ .compatible = "ti,j721e-dss", .data = &dispc_j721e_feats, },
>  	{ }