> -----Original Message-----
> From: Govindapillai, Vinod <[email protected]>
> Sent: Monday, October 27, 2025 7:10 PM
> To: [email protected]; [email protected]
> Cc: Govindapillai, Vinod <[email protected]>; Sousa, Gustavo
> <[email protected]>; Nikula, Jani <[email protected]>; Syrjala,
> Ville
> <[email protected]>; Shankar, Uma <[email protected]>
> Subject: [PATCH v2 1/4] drm/i915/xe3p_lpd: Extend FBC support to UINT16
> formats
>
> From: Sai Teja Pottumuttu <[email protected]>
>
> Starting Xe3p_LPD, FBC is supported on UINT16 formats as well. Also
> UINT16 being a 64bpp format, will use cpp of 8 for cfb stride and thus size
> calculations.
>
> v2: simplify getting the cpp per format (Ville)
> simplify the pixel format is valid for xe3p_lp (Vinod)
Looks Good to me.
Reviewed-by: Uma Shankar <[email protected]>
> Cc: Shekhar Chauhan <[email protected]>
> BSpec: 68881, 68904, 69560
> Signed-off-by: Sai Teja Pottumuttu <[email protected]>
> Signed-off-by: Gustavo Sousa <[email protected]>
> Signed-off-by: Vinod Govindapillai <[email protected]>
> ---
> drivers/gpu/drm/i915/display/intel_fbc.c | 33 ++++++++++++++++++++----
> 1 file changed, 28 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_fbc.c
> b/drivers/gpu/drm/i915/display/intel_fbc.c
> index 10ef3136dadc..83dcf62e4ebe 100644
> --- a/drivers/gpu/drm/i915/display/intel_fbc.c
> +++ b/drivers/gpu/drm/i915/display/intel_fbc.c
> @@ -141,15 +141,18 @@ static unsigned int intel_fbc_plane_stride(const struct
> intel_plane_state *plane
> return stride;
> }
>
> -static unsigned int intel_fbc_cfb_cpp(void)
> +static unsigned int intel_fbc_cfb_cpp(const struct intel_plane_state
> +*plane_state)
> {
> - return 4; /* FBC always 4 bytes per pixel */
> + const struct drm_framebuffer *fb = plane_state->hw.fb;
> + unsigned int cpp = fb->format->cpp[0];
> +
> + return max(cpp, 4);
> }
>
> /* plane stride based cfb stride in bytes, assuming 1:1 compression limit */
> static
> unsigned int intel_fbc_plane_cfb_stride(const struct intel_plane_state
> *plane_state) {
> - unsigned int cpp = intel_fbc_cfb_cpp();
> + unsigned int cpp = intel_fbc_cfb_cpp(plane_state);
>
> return intel_fbc_plane_stride(plane_state) * cpp; } @@ -203,7 +206,7
> @@ static unsigned int intel_fbc_cfb_stride(const struct intel_plane_state
> *plane_s
> struct intel_display *display =
> to_intel_display(plane_state->uapi.plane-
> >dev);
> unsigned int stride = intel_fbc_plane_cfb_stride(plane_state);
> unsigned int width = drm_rect_width(&plane_state->uapi.src) >> 16;
> - unsigned int cpp = intel_fbc_cfb_cpp();
> + unsigned int cpp = intel_fbc_cfb_cpp(plane_state);
>
> return _intel_fbc_cfb_stride(display, cpp, width, stride); } @@
> -1081,11
> +1084,31 @@ static bool lnl_fbc_pixel_format_is_valid(const struct
> intel_plane_state *plane_
> }
> }
>
> +static bool xe3p_lpd_fbc_pixel_format_is_valid(const struct
> +intel_plane_state *plane_state) {
> + const struct drm_framebuffer *fb = plane_state->hw.fb;
> +
> + if (lnl_fbc_pixel_format_is_valid(plane_state))
> + return true;
> +
> + switch (fb->format->format) {
> + case DRM_FORMAT_XRGB16161616:
> + case DRM_FORMAT_XBGR16161616:
> + case DRM_FORMAT_ARGB16161616:
> + case DRM_FORMAT_ABGR16161616:
> + return true;
> + default:
> + return false;
> + }
> +}
> +
> static bool pixel_format_is_valid(const struct intel_plane_state
> *plane_state) {
> struct intel_display *display =
> to_intel_display(plane_state->uapi.plane-
> >dev);
>
> - if (DISPLAY_VER(display) >= 20)
> + if (DISPLAY_VER(display) >= 35)
> + return xe3p_lpd_fbc_pixel_format_is_valid(plane_state);
> + else if (DISPLAY_VER(display) >= 20)
> return lnl_fbc_pixel_format_is_valid(plane_state);
> else if (DISPLAY_VER(display) >= 5 || display->platform.g4x)
> return g4x_fbc_pixel_format_is_valid(plane_state);
> --
> 2.43.0
