Re: [PATCH v3 6/7] drm/meson: overlay: setup overlay for Amlogic FBC Memory Saving mode

From: Neil Armstrong
Date: Tue Mar 24 2020 - 10:24:22 EST


On 24/03/2020 15:20, Neil Armstrong wrote:
> Setup the Amlogic FBC decoder for the VD1 video overlay plane to use
> a different superblock size for the Memory Saving mode.
>
> Signed-off-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
> ---
> drivers/gpu/drm/meson/meson_overlay.c | 14 ++++++++++++--
> include/uapi/drm/drm_fourcc.h | 16 +++++++++++++++-
> 2 files changed, 27 insertions(+), 3 deletions(-)
>

[...]

> --- a/include/uapi/drm/drm_fourcc.h
> +++ b/include/uapi/drm/drm_fourcc.h
> @@ -840,6 +840,19 @@ extern "C" {
> */
> #define DRM_FORMAT_MOD_AMLOGIC_FBC_LAYOUT_BASIC (1ULL << 0)
>
> +/*
> + * Amlogic FBC Scatter Memory layout
> + *
> + * Indicates the header contains IOMMU references to the compressed
> + * frames content to optimize memory access and layout.
> + *
> + * In this mode, only the header memory address is needed, thus the
> + * content memory organization is tied to the current producer
> + * execution and cannot be saved/dumped neither transferrable between
> + * Amlogic SoCs supporting this modifier.
> + */
> +#define DRM_FORMAT_MOD_AMLOGIC_FBC_LAYOUT_SCATTER (2ULL << 0)
> +
> /*
> * Amlogic FBC Layout Options
> */
> @@ -852,7 +865,8 @@ extern "C" {
> * memory.
> *
> * This mode reduces body layout to 3072 bytes per 64x32 superblock with
> - * the basic layout.
> + * the basic layout and 3200 bytes per 64x32 superblock combined with
> + * the scatter layout.
> */
> #define DRM_FORMAT_MOD_AMLOGIC_FBC_MEM_SAVING (1ULL << 8)
>
>

Oops a commit got lost in the process... this change should be independent.

Neil