1.. SPDX-License-Identifier: GPL-2.0 2 3========================================= 4Rockchip Camera Interface (CIF) 5========================================= 6 7Introduction 8============ 9 10The Rockchip Camera Interface (CIF) is featured in many Rockchip SoCs in 11different variants. 12The different variants are combinations of common building blocks, such as 13 14* INTERFACE blocks of different types, namely 15 16 * the Digital Video Port (DVP, a parallel data interface) 17 * the interface block for the MIPI CSI-2 receiver 18 19* CROP units 20 21* MIPI CSI-2 receiver (not available on all variants): This unit is referred 22 to as MIPI CSI HOST in the Rockchip documentation. 23 Technically, it is a separate hardware block, but it is strongly coupled to 24 the CIF and therefore included here. 25 26* MUX units (not available on all variants) that pass the video data to an 27 image signal processor (ISP) 28 29* SCALE units (not available on all variants) 30 31* DMA engines that transfer video data into system memory using a 32 double-buffering mechanism called ping-pong mode 33 34* Support for four streams per INTERFACE block (not available on all 35 variants), e.g., for MIPI CSI-2 Virtual Channels (VCs) 36 37This document describes the different variants of the CIF, their hardware 38layout, as well as their representation in the media controller centric rkcif 39device driver, which is located under drivers/media/platform/rockchip/rkcif. 40 41Variants 42======== 43 44Rockchip PX30 Video Input Processor (VIP) 45----------------------------------------- 46 47The PX30 Video Input Processor (VIP) features a digital video port that accepts 48parallel video data or BT.656. 49Since these protocols do not feature multiple streams, the VIP has one DMA 50engine that transfers the input video data into system memory. 51 52The rkcif driver represents this hardware variant by exposing one V4L2 subdevice 53(the DVP INTERFACE/CROP block) and one V4L2 device (the DVP DMA engine). 54 55Rockchip RK3568 Video Capture (VICAP) 56------------------------------------- 57 58The RK3568 Video Capture (VICAP) unit features a digital video port and a MIPI 59CSI-2 receiver that can receive video data independently. 60The DVP accepts parallel video data, BT.656 and BT.1120. 61Since the BT.1120 protocol may feature more than one stream, the RK3568 VICAP 62DVP features four DMA engines that can capture different streams. 63Similarly, the RK3568 VICAP MIPI CSI-2 receiver features four DMA engines to 64handle different Virtual Channels (VCs). 65 66The rkcif driver represents this hardware variant by exposing up the following 67V4L2 subdevices: 68 69* rkcif-dvp0: INTERFACE/CROP block for the DVP 70 71and the following video devices: 72 73* rkcif-dvp0-id0: The support for multiple streams on the DVP is not yet 74 implemented, as it is hard to find test hardware. Thus, this video device 75 represents the first DMA engine of the RK3568 DVP. 76 77.. kernel-figure:: rkcif-rk3568-vicap.dot 78 :alt: Topology of the RK3568 Video Capture (VICAP) unit 79 :align: center 80 81Rockchip RK3588 Video Capture (VICAP) 82------------------------------------- 83 84The RK3588 Video Capture (VICAP) unit features a digital video port and six 85MIPI CSI-2 capture interfaces that can receive video data independently. 86The DVP accepts parallel video data, BT.656 and BT.1120. 87Since the BT.1120 protocol may feature more than one stream, the RK3588 VICAP 88DVP features four DMA engines that can capture different streams. 89Similarly, the RK3588 VICAP MIPI CSI-2 receivers feature four DMA engines each 90to handle different Virtual Channels (VCs). 91 92The rkcif driver represents this hardware variant by exposing the following 93V4L2 subdevices: 94 95* dw-mipi-csi2rx fdd30000.csi: MIPI CSI-2 receiver connected to MIPI DPHY0 96* dw-mipi-csi2rx fdd50000.csi: MIPI CSI-2 receiver connected to MIPI DPHY1 97* rkcif-mipi2: INTERFACE/CROP block for the MIPI CSI-2 receiver connected to 98 MIPI DPHY0 99* rkcif-mipi4: INTERFACE/CROP block for the MIPI CSI-2 receiver connected to 100 MIPI DPHY1 101 102and the following video devices: 103 104* rkcif-mipi2-id{0,1,2,3}: The DMA engines connected to the rkcif-mipi2 105 INTERFACE/CROP block. 106* rkcif-mipi4-id{0,1,2,3}: The DMA engines connected to the rkcif-mipi4 107 INTERFACE/CROP block. 108 109.. kernel-figure:: rkcif-rk3588-vicap.dot 110 :alt: Topology of the RK3588 Video Capture (VICAP) unit 111 :align: center 112