linux-kernel - [PATCH v6 2/2] Documentation/gpu: Add Synaptics tiling formats documentation

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20230322082910.115371-3-randy.li@synaptics.com>
Date:   Wed, 22 Mar 2023 16:29:10 +0800
From:   Hsia-Jun Li <randy.li@...aptics.com>
To:     dri-devel@...ts.freedesktop.org
Cc:     ayaka@...lik.info, maarten.lankhorst@...ux.intel.com,
        mripard@...nel.org, tzimmermann@...e.de, airlied@...il.com,
        daniel@...ll.ch, linux-kernel@...r.kernel.org, tfiga@...omium.org,
        nicolas@...fresne.ca, laurent.pinchart@...asonboard.com,
        ribalda@...omium.org, Hsia-Jun Li <randy.li@...aptics.com>
Subject: [PATCH v6 2/2] Documentation/gpu: Add Synaptics tiling formats documentation

From: Randy Li <ayaka@...lik.info>

Signed-off-by: Randy Li <ayaka@...lik.info>
Signed-off-by: Hsia-Jun(Randy) Li <randy.li@...aptics.com>
---
 Documentation/gpu/synaptics.rst | 81 +++++++++++++++++++++++++++++++++
 1 file changed, 81 insertions(+)
 create mode 100644 Documentation/gpu/synaptics.rst

diff --git a/Documentation/gpu/synaptics.rst b/Documentation/gpu/synaptics.rst
new file mode 100644
index 000000000000..4185ca536bf1
--- /dev/null
+++ b/Documentation/gpu/synaptics.rst
@@ -0,0 +1,81 @@
+.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
+
+================
+Synaptics Tiling
+================
+
+The tiling pixel formats in Synpatics Video Smart platform have
+many variants. Tiles could form the group of tiles, pixels within
+the group (nearest) width and height are stored into tile.
+Meanwhile, the tile in a group may not follow dimension layout,
+tile could form a small group of tiles, then that (sub)group
+of tiles would form a bigger group. We won't describe the dimension
+layout inside the group of tiles here. The layout of the group
+of tiles is fixed with the group width and height parameters
+in the same generation of the platform.
+
+Compression
+===========
+The proprietary lossless image compression protocol in Synaptics
+could minimizes the amount of data transferred (less memory bandwidth
+consumption) between devices. It would usually apply to the tiling
+pixel format.
+
+Each component would request an extra page aligned length buffer
+for storing the compression meta data. Also a 32 bytes parameters
+set would come with a compression meta data buffer.
+
+The component here corresponds to a signal type (i.e. Luma, chroma).
+They could be encoded into one or multiple metadata planes, but
+their compression parameters still would be individual.
+
+Pixel format modifiers
+======================
+Addition alignment requirement for stride and size of a memory plane
+could apply beyond what has been mentioned below. Remember always
+negotiating with all the devices in pipeline before allocation.
+
+.. flat-table:: Synpatics Image Format Modifiers
+
+	* - Identifier
+	  - Fourcc
+	  - Details
+
+	* - DRM_FORMAT_MOD_SYNA_V4H1
+	  - DRM_FORMAT_NV12
+	  - The plain uncompressed 8 bits tile format. It sounds similar to
+	Intel's Y-tile. but it won't take any pixel from the next X direction
+	in a tile group. The line stride and image height must be aligned to
+	a multiple of 16. The height of chrominance plane would plus 8.
+
+	* - DRM_FORMAT_MOD_SYNA_V4H3P8
+	  - DRM_FORMAT_NV15
+	  - The plain uncompressed 10 bits tile format. It stores pixel in 2D
+	3x4 tiles with a 8bits padding to each of tile. Then a tile is in a
+	128 bits cache line.
+
+	* - DRM_FORMAT_MOD_SYNA_V4H1_64L4_COMPRESSED
+	  - DRM_FORMAT_NV12
+	  - Group of tiles and compressed variant of ``DRM_FORMAT_MOD_SYNA_V4H1``.
+    A group of tiles would contain 64x4 pixels, where a tile has 1x4
+    pixel.
+
+	* - DRM_FORMAT_MOD_SYNA_V4H3P8_64L4_COMPRESSED
+	  - DRM_FORMAT_NV15
+	  - Group of tiles and compressed variant of ``DRM_FORMAT_MOD_SYNA_V4H3P8``.
+     A group of tiles would contains 48x4 pixels, where a tile has 3x4 pixels
+     and a 8 bits padding in the end of a tile. A group of tiles would
+     be 256 bytes.
+
+	* - ``DRM_FORMAT_MOD_SYNA_V4H1_128L128_COMPRESSED``
+	  - DRM_FORMAT_NV12
+	  - Group of tiles and compressed variant of ``DRM_FORMAT_MOD_SYNA_V4H1``.
+    A group of tiles would contain 128x32 pixels, where a tile has 1x4
+    pixel.
+
+	* - ``DRM_FORMAT_MOD_SYNA_V4H3P8_128L128_COMPRESSED``
+	  - DRM_FORMAT_NV15
+	  - Group of tiles and compressed variant of ``DRM_FORMAT_MOD_SYNA_V4H3P8``.
+     A group of tiles would contains 96x128 pixels, where a tile has 3x4 pixels
+     and a 8 bits padding in the end of a tile. A group of tiles would
+     be 16 KiB.
-- 
2.17.1