Re: [PATCH v7 10/22] drm/rockchip: vop2: Fix YUV444 output

[Nicolas Frattaroli <nicolas.frattaroli@collabora.com>]

On Thursday, 22 January 2026 09:28:54 Central European Standard Time Andy Yan wrote:
> 
> Hello Nicolas，
> 
> At 2026-01-21 22:45:17, "Nicolas Frattaroli" <nicolas.frattaroli@collabora.com> wrote:
> >YUV444 (aka YCbCr444) output isn't working quite right on RK3588. The
> >resulting image on the display, while identifying itself as YUV444, has
> >some components swapped, even after adding the necessary DRM formats to
> >the conversion functions.
> >
> >Judging by downstream, this is because YUV444 also needs an rb swap
> >performed in the AFBC case.
> >
> >Add the DRM formats to the appropriate switch statements, and add a
> >function for checking whether an rb swap needs to be performed in the
> >AFBC case.
> >
> >Fixes: 604be85547ce ("drm/rockchip: Add VOP2 driver")
> >Signed-off-by: Nicolas Frattaroli <nicolas.frattaroli@collabora.com>
> >---
> > drivers/gpu/drm/rockchip/rockchip_drm_vop2.c | 19 +++++++++++++++++++
> > 1 file changed, 19 insertions(+)
> >
> >diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c b/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c
> >index ec3b4fde10db..469c63dd97d5 100644
> >--- a/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c
> >+++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c
> >@@ -176,6 +176,7 @@ static enum vop2_data_format vop2_convert_format(u32 format)
> > 	case DRM_FORMAT_ARGB2101010:
> > 	case DRM_FORMAT_XBGR2101010:
> > 	case DRM_FORMAT_ABGR2101010:
> >+	case DRM_FORMAT_VUY101010:
> > 		return VOP2_FMT_XRGB101010;
> > 	case DRM_FORMAT_XRGB8888:
> > 	case DRM_FORMAT_ARGB8888:
> >@@ -184,6 +185,7 @@ static enum vop2_data_format vop2_convert_format(u32 format)
> > 		return VOP2_FMT_ARGB8888;
> > 	case DRM_FORMAT_RGB888:
> > 	case DRM_FORMAT_BGR888:
> >+	case DRM_FORMAT_VUY888:
> > 		return VOP2_FMT_RGB888;
> > 	case DRM_FORMAT_RGB565:
> > 	case DRM_FORMAT_BGR565:
> >@@ -225,6 +227,7 @@ static enum vop2_afbc_format vop2_convert_afbc_format(u32 format)
> > 	case DRM_FORMAT_ARGB2101010:
> > 	case DRM_FORMAT_XBGR2101010:
> > 	case DRM_FORMAT_ABGR2101010:
> >+	case DRM_FORMAT_VUY101010:
> > 		return VOP2_AFBC_FMT_ARGB2101010;
> > 	case DRM_FORMAT_XRGB8888:
> > 	case DRM_FORMAT_ARGB8888:
> >@@ -233,6 +236,7 @@ static enum vop2_afbc_format vop2_convert_afbc_format(u32 format)
> > 		return VOP2_AFBC_FMT_ARGB8888;
> > 	case DRM_FORMAT_RGB888:
> > 	case DRM_FORMAT_BGR888:
> >+	case DRM_FORMAT_VUY888:
> 
> How did you test this format? It seems tools like modetest don’t support testing this pattern.
> 

Hi Andy,

using the rest of this series, which implements the "color format"
DRM property, and the corresponding weston MR that makes use of it[1].

I create a ~/.config/weston.ini with the following contents:

    [output]
    name=HDMI-A-1
    color-format=yuv444

This will make Weston try to set the output format to 10-bit YUV444. To
limit it to 8-bit, you can add `max-bpc=8`. The monitor's EDID needs to
report YUV444 support, otherwise that Weston version won't let you set
this property.

Link: https://gitlab.freedesktop.org/wayland/weston/-/merge_requests/1859 [1]

Kind regards,
Nicolas Frattaroli

> 
> 
> > 		return VOP2_AFBC_FMT_RGB888;
> > 	case DRM_FORMAT_RGB565:
> > 	case DRM_FORMAT_BGR565:
> >@@ -270,6 +274,19 @@ static bool vop2_win_rb_swap(u32 format)
> > 	}
> > }
> > 
> >+static bool vop2_afbc_rb_swap(u32 format)
> >+{
> >+	switch (format) {
> >+	case DRM_FORMAT_NV24:
> >+	case DRM_FORMAT_NV30:
> >+	case DRM_FORMAT_VUY888:
> >+	case DRM_FORMAT_VUY101010:
> >+		return true;
> >+	default:
> >+		return false;
> >+	}
> >+}
> >+
> > static bool vop2_afbc_uv_swap(u32 format)
> > {
> > 	switch (format) {
> >@@ -1291,6 +1308,7 @@ static void vop2_plane_atomic_update(struct drm_plane *plane,
> > 		 /* It's for head stride, each head size is 16 byte */
> > 		stride = ALIGN(stride, block_w) / block_w * 16;
> > 
> >+		rb_swap = vop2_afbc_rb_swap(fb->format->format);
> > 		uv_swap = vop2_afbc_uv_swap(fb->format->format);
> > 		/*
> > 		 * This is a workaround for crazy IC design, Cluster
> >@@ -1308,6 +1326,7 @@ static void vop2_plane_atomic_update(struct drm_plane *plane,
> > 			vop2_win_write(win, VOP2_WIN_AFBC_ENABLE, 1);
> > 		vop2_win_write(win, VOP2_WIN_AFBC_FORMAT, afbc_format);
> > 		vop2_win_write(win, VOP2_WIN_AFBC_UV_SWAP, uv_swap);
> >+		vop2_win_write(win, VOP2_WIN_AFBC_RB_SWAP, rb_swap);
> > 		/*
> > 		 * On rk3566/8, this bit is auto gating enable,
> > 		 * but this function is not work well so we need
> >
>