1dae86bb6SJammy Huang.. SPDX-License-Identifier: GPL-2.0 2dae86bb6SJammy Huang 3dae86bb6SJammy Huang.. include:: <isonum.txt> 4dae86bb6SJammy Huang 5dae86bb6SJammy HuangASPEED video driver 6dae86bb6SJammy Huang=================== 7dae86bb6SJammy Huang 8dae86bb6SJammy HuangASPEED Video Engine found on AST2400/2500/2600 SoC supports high performance 9dae86bb6SJammy Huangvideo compressions with a wide range of video quality and compression ratio 10dae86bb6SJammy Huangoptions. The adopted compressing algorithm is a modified JPEG algorithm. 11dae86bb6SJammy Huang 12dae86bb6SJammy HuangThere are 2 types of compressions in this IP. 13dae86bb6SJammy Huang 14dae86bb6SJammy Huang* JPEG JFIF standard mode: for single frame and management compression 15dae86bb6SJammy Huang* ASPEED proprietary mode: for multi-frame and differential compression. 16dae86bb6SJammy Huang Support 2-pass (high quality) video compression scheme (Patent pending by 17dae86bb6SJammy Huang ASPEED). Provide visually lossless video compression quality or to reduce 18dae86bb6SJammy Huang the network average loading under intranet KVM applications. 19dae86bb6SJammy Huang 20dae86bb6SJammy HuangVIDIOC_S_FMT can be used to choose which format you want. V4L2_PIX_FMT_JPEG 21dae86bb6SJammy Huangstands for JPEG JFIF standard mode; V4L2_PIX_FMT_AJPG stands for ASPEED 22dae86bb6SJammy Huangproprietary mode. 23dae86bb6SJammy Huang 24dae86bb6SJammy HuangMore details on the ASPEED video hardware operations can be found in 25dae86bb6SJammy Huang*chapter 6.2.16 KVM Video Driver* of SDK_User_Guide which available on 26*c3fc8067SJammy Huang`github <https://github.com/AspeedTech-BMC/openbmc/releases/>`__. 27dae86bb6SJammy Huang 28dae86bb6SJammy HuangThe ASPEED video driver implements the following driver-specific control: 29dae86bb6SJammy Huang 30dae86bb6SJammy Huang``V4L2_CID_ASPEED_HQ_MODE`` 31dae86bb6SJammy Huang--------------------------- 32dae86bb6SJammy Huang Enable/Disable ASPEED's High quality mode. This is a private control 33dae86bb6SJammy Huang that can be used to enable high quality for aspeed proprietary mode. 34dae86bb6SJammy Huang 35dae86bb6SJammy Huang.. flat-table:: 36dae86bb6SJammy Huang :header-rows: 0 37dae86bb6SJammy Huang :stub-columns: 0 38dae86bb6SJammy Huang :widths: 1 4 39dae86bb6SJammy Huang 40dae86bb6SJammy Huang * - ``(0)`` 41dae86bb6SJammy Huang - ASPEED HQ mode is disabled. 42dae86bb6SJammy Huang * - ``(1)`` 43dae86bb6SJammy Huang - ASPEED HQ mode is enabled. 44dae86bb6SJammy Huang 45dae86bb6SJammy Huang``V4L2_CID_ASPEED_HQ_JPEG_QUALITY`` 46dae86bb6SJammy Huang----------------------------------- 47dae86bb6SJammy Huang Define the quality of ASPEED's High quality mode. This is a private control 48dae86bb6SJammy Huang that can be used to decide compression quality if High quality mode enabled 49dae86bb6SJammy Huang . Higher the value, better the quality and bigger the size. 50dae86bb6SJammy Huang 51dae86bb6SJammy Huang.. flat-table:: 52dae86bb6SJammy Huang :header-rows: 0 53dae86bb6SJammy Huang :stub-columns: 0 54dae86bb6SJammy Huang :widths: 1 4 55dae86bb6SJammy Huang 56dae86bb6SJammy Huang * - ``(1)`` 57dae86bb6SJammy Huang - minimum 58dae86bb6SJammy Huang * - ``(12)`` 59dae86bb6SJammy Huang - maximum 60dae86bb6SJammy Huang * - ``(1)`` 61dae86bb6SJammy Huang - step 62dae86bb6SJammy Huang * - ``(1)`` 63dae86bb6SJammy Huang - default 64dae86bb6SJammy Huang 65dae86bb6SJammy Huang**Copyright** |copy| 2022 ASPEED Technology Inc. 66