ec5722adb8
There have suggestions to bake pitch alignment, address alignment, contiguous memory or other placement (hidden VRAM, GTT/BAR, etc) constraints into modifiers. Last time this was brought up it seemed like the consensus was to not allow this. Document this in drm_fourcc.h. There are several reasons for this. - Encoding all of these constraints in the modifiers would explode the search space pretty quickly (we only have 64 bits to work with). - Modifiers need to be unambiguous: a buffer can only have a single modifier. - Modifier users aren't expected to parse modifiers (except drivers). v2: add paragraph about aliases (Daniel) v3: fix unrelated changes sent with the patch v4: disambiguate users between driver and higher-level programs (Brian, Daniel) v5: fix AFBC example (Brian, Daniel) v6: remove duplicated paragraph (Daniel) Signed-off-by: Simon Ser <contact@emersion.fr> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Reviewed-by: Brian Starkey <brian.starkey@arm.com> Cc: Daniel Stone <daniel@fooishbar.org> Cc: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl> Cc: Dave Airlie <airlied@gmail.com> Cc: Marek Olšák <maraeo@gmail.com> Cc: Alex Deucher <alexdeucher@gmail.com> Cc: Neil Armstrong <narmstrong@baylibre.com> Cc: Michel Dänzer <michel@daenzer.net> Link: https://patchwork.freedesktop.org/patch/msgid/MGwgeXojKNdNXjCxuMhRlwcJM4vdYph_WJcMeGPPGMcRKtHV41XAXlh2tCc-pPJZCAhS3gwbWMWTd8f03NBA2ZYKfr0QxLhcPivpopr5c6M=@emersion.fr |
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| .. | ||
| amdgpu_drm.h | ||
| armada_drm.h | ||
| drm.h | ||
| drm_fourcc.h | ||
| drm_mode.h | ||
| drm_sarea.h | ||
| etnaviv_drm.h | ||
| exynos_drm.h | ||
| i810_drm.h | ||
| i915_drm.h | ||
| lima_drm.h | ||
| mga_drm.h | ||
| msm_drm.h | ||
| nouveau_drm.h | ||
| omap_drm.h | ||
| panfrost_drm.h | ||
| qxl_drm.h | ||
| r128_drm.h | ||
| radeon_drm.h | ||
| savage_drm.h | ||
| sis_drm.h | ||
| tegra_drm.h | ||
| v3d_drm.h | ||
| vc4_drm.h | ||
| vgem_drm.h | ||
| via_drm.h | ||
| virtgpu_drm.h | ||
| vmwgfx_drm.h | ||