Decoupling link training between video source and video sink in extended environment

Abstract

In some embodiments, a system for providing DisplayPort communication over an extended medium is provided. The system includes an upstream-facing port device (UFP device) and a downstream-facing port device (DFP device). The UFP device is configured to perform link training with a DisplayPort source device using a first DisplayPort configuration data (DPCD). The DFP device is configured to perform link training with the DisplayPort sink device using a second DPCD that is different from the first DPCD. The UFP device is configured to extract video data from DisplayPort data received from the DisplayPort source device and transmit the video data to the DFP device. The DFP device is configured to receive the video data, generate DisplayPort data as specified by the second DPCD, and transmit the generated DisplayPort data as specified by the second DPCD to the DisplayPort sink device.

Description

[0001] Cross-reference to related applications

[0002] This application claims the benefit of provisional application number 63 / 057152, filed on July 27, 2020, the entire disclosure of which is incorporated herein by reference for all purposes. Background Technology

[0003] DisplayPort communication is described in detail in at least VESA's "VESA DisplayPort Standard, Version 1.4," published on March 1, 2016. This document (the contents of which are known to those skilled in the art) is incorporated herein by reference in its entirety, together with any previous versions or related documents mentioned therein (collectively, the "DisplayPort Specification"), for all purposes. The DisplayPort Specification describes the physical and logical techniques for communication between a DisplayPort source device that generates video (and in some embodiments, audio) and a DisplayPort destination device that presents video (and in some embodiments, audio). The DisplayPort Specification also describes topologies in which one or more branch devices (similar to repeaters, splitters, or hubs) exist between the DisplayPort source device and the DisplayPort destination device.

[0004] The DisplayPort specification includes limitations on the cable length connecting DisplayPort source and destination devices, as well as other specific requirements regarding the physical construction of the cable. For example, full-bandwidth transmission over passive cable is limited to a cable length of three meters. Furthermore, the DisplayPort specification describes direct communication between DisplayPort source and destination devices, but does not permit any manipulation of the video or audio content between them. The DisplayPort specification also assumes a direct link between a given DisplayPort source and destination device, and therefore assumes the use of a single communication format between them.

[0005] The desired devices and technologies are those that allow DisplayPort source and sink devices, which otherwise conform to the DisplayPort specification, to communicate over extended media, regardless of the DisplayPort specification's distance limitations and media requirements. Summary of the Invention

[0006] This overview is provided to introduce, in a simplified form, a series of concepts that will be further described in the detailed embodiments described below. This overview is not intended to identify key features of the claimed subject matter, nor is it intended to help determine the scope of the claimed subject matter.

[0007] In some embodiments, a system is provided for providing DisplayPort communication via an extended medium. The system includes an extended medium; an upstream-facing port device (UFP device); and a downstream-facing port device (DFP device). The UFP device is communicatively coupled to a DisplayPort source device and the extended medium. The DFP device is communicatively coupled to a DisplayPort sink device and the extended medium. The UFP device is configured to perform link training with the DisplayPort source device using first DisplayPort configuration data (DPCD), wherein the first DPCD is associated with the DisplayPort source device; receive DisplayPort data from the DisplayPort source device as specified by the first DPCD; extract video data from the DisplayPort data received from the DisplayPort source device; and transmit the video data to the DFP device via the extended medium. The DFP device is configured to perform link training with the DisplayPort destination device using a second DisplayPort configuration data (DPCD), wherein the second DPCD is associated with the DisplayPort destination device; receive video data from the UFP device; generate DisplayPort data as specified by the second DPCD, wherein the generated DisplayPort data includes the video data; and transmit the generated DisplayPort data as specified by the second DPCD to the DisplayPort destination device. The first DPCD is different from the second DPCD.

[0008] In some embodiments, a downstream-facing port device (DFP device) is provided. The DFP device includes a first interface, a second interface, and logic. The first interface is configured to be communicatively coupled to an extension medium. The second interface is configured to be communicatively coupled to a DisplayPort sink device. The logic, in response to actions performed by the DFP device, causes the DFP device to perform the following actions: perform link training with the DisplayPort sink device using first DisplayPort configuration data (DPCD), wherein the first DPCD is associated with the DisplayPort sink device; receive video data via the first interface, wherein the video data is extracted from DisplayPort data received from an upstream-facing port device (UFP device) using a link trained using second DisplayPort configuration data (DPCD); generate DisplayPort data as specified by the first DPCD, wherein the generated DisplayPort data includes the video data; and transmit DisplayPort data as specified by the first DPCD to the DisplayPort sink device. The first DPCD is different from the second DPCD.

[0009] In some embodiments, a non-transitory computer-readable medium is provided having computer-executable instructions stored thereon. These instructions, in response to execution by the downstream-facing port device (DFP device), cause the DFP device to perform actions including: performing link training with the DisplayPort sink device using first DisplayPort configuration data (DPCD), wherein the first DPCD is associated with the DisplayPort sink device; receiving video data from an extended interface, wherein the video data is extracted from DisplayPort data received from an upstream-facing port device (UFP device) using a link trained by using second DisplayPort configuration data (DPCD); generating DisplayPort data as specified by the first DPCD, wherein the generated DisplayPort data includes the video data; and transmitting DisplayPort data as specified by the first DPCD to the DisplayPort sink device. The first DPCD is different from the second DPCD. Attached Figure Description

[0010] The foregoing aspects and many incidental features of the invention will be more readily recognized and better understood by referring to the following detailed description in conjunction with the accompanying drawings, in which:

[0011] Figure 1A and Figure 1BThese are block diagrams illustrating non-limiting example embodiments of upstream-facing port devices (UFP devices) and downstream-facing port devices (DFP devices) according to various aspects of this disclosure.

[0012] Figure 2 This is a block diagram illustrating a non-limiting example embodiment of an upstream video engine according to various aspects of this disclosure.

[0013] Figure 3 This is a block diagram illustrating a non-limiting example embodiment of a downstream video engine according to various aspects of this disclosure.

[0014] Figure 4 This is a block diagram illustrating a non-limiting example embodiment of an extended interface engine according to various aspects of this disclosure.

[0015] Figure 5A and Figure 5B This is a flowchart illustrating a non-limiting example embodiment of a method for establishing DisplayPort communication via an extended medium according to various aspects of this disclosure. Detailed Implementation

[0016] In some embodiments disclosed herein, extension devices, such as upstream-facing port devices (UFP devices) and downstream-facing port devices (DFP devices), are connected via an extension medium such as a network. The UFP device forms a DisplayPort connection with a DisplayPort source device, and the DFP device forms a DisplayPort connection with a DisplayPort destination device. When the UFP device and DFP device are paired, DisplayPort video and / or audio information from the DisplayPort source device coupled to the UFP device can be presented by the DisplayPort destination device coupled to the DFP device. In some embodiments disclosed herein, the UFP device can use a first DisplayPort configuration data (DPCD) associated with the DisplayPort source device to train the DisplayPort link between the UFP device and the DisplayPort source device, and the DFP device can use a different second DPCD associated with the DisplayPort destination device to train the DisplayPort link between the DFP device and the DisplayPort destination device. The UFP device can extract video data from DisplayPort data received from the DisplayPort source device according to the first DPCD and transmit the video data to the DFP device via the extension medium. The DFP device can then receive video data via an extended medium, create DisplayPort data including the video data according to the second DPCD, and transmit the DisplayPort data to the DisplayPort destination device according to the second DPCD. The first DPCD may differ from the second DPCD in one or more aspects.

[0017] Figure 1A and Figure 1B These are block diagrams illustrating non-limiting example embodiments of upstream-facing port devices (UFP devices) and downstream-facing port devices (DFP devices) according to various aspects of this disclosure. Figure 1A The image shows a DisplayPort source device (DP source device 102), an upstream-facing port device (UFP device) 104, and an extension medium 106. The DP source device 102 can be any type of device capable of transmitting DisplayPort information, including but not limited to desktop computing devices, laptop computing devices, tablet computing devices, rack-mounted computing devices, external graphics cards, video processing systems, etc.

[0018] DP source device 102 includes a host interface 112 that is communicatively coupled to an upstream-facing port 120 of UFP device 104. In some embodiments, host interface 112 and upstream-facing port 120 may include a DisplayPort connector. In some embodiments, host interface 112 and upstream-facing port 120 may include connectors defined by another standard for communication via DisplayPort, including but not limited to USB Type-C connectors and / or DockPort connectors. The connection between DP source device 102 and UFP device 104 via host interface 112 and upstream-facing port 120 may include cables and other hardware as described in (or compatible with) the DisplayPort specification and known to those skilled in the art.

[0019] As shown, the UFP device 104 includes an upstream processor 118. In some embodiments, the upstream processor 118 may be implemented using a field-programmable gate array (FPGA), an application-specific integrated circuit (ASIC), a microcontroller, and / or any other suitable type of computing device or integrated circuit. The upstream processor 118 may be configured to provide an upstream video engine 116, an upstream AUX engine 114, and a DP destination emulation engine 110.

[0020] Typically, as used in this article, the term "engine" refers to logic implemented in hardware or that can be written in languages ​​such as C, C++, C#, COBOL, or JAVA. TM Software engines are written in programming languages ​​such as PHP, Perl, HTML, CSS, JavaScript, VBScript, ASPX, and Go. Engines implemented in hardware can be designed using Hardware Description Languages ​​(HDLs). Software engines can be compiled into executable programs or written in interpreted programming languages. An engine can be invoked from other engines or from itself. Generally, the engine described herein refers to a logical module that can be merged with other engines or divided into multiple sub-engines. Engines can be stored on any type of computer-readable medium or computer storage device and can be stored on and executed by one or more general-purpose computers, resulting in a dedicated computer configured to provide the engine or application. Engines can also be implemented using floating-point gate arrays (FPGAs), application-specific integrated circuits (ASICs), microcontrollers, or any other suitable type of integrated circuit computing device.

[0021] In some embodiments, the upstream video engine 116 is configured to receive one or more DisplayPort channels from an upstream-facing port 120. The upstream video engine 116 is configured to recover video and / or audio signals from the DisplayPort channels and provide such video and / or audio signals to the expansion interface 108. In some embodiments, the upstream video engine 116 may configurably perform further processing on the video and / or audio before providing it to the expansion interface 108, including but not limited to changing the bit rate of the information, encrypting the information, upsampling or downsampling the information, and / or any other type of processing. In some embodiments, the upstream video engine 116 is also configured to selectively provide a hot-plug detection (HPD) signal to the DP source device 102 via the upstream-facing port 120. The upstream video engine 116 may selectively provide the HPD signal based on instructions received from the upstream AUX engine 114, the DP sink emulation engine 110, or other components of the UFP device 104. Figure 2 Further illustration and description of exemplary embodiments of the upstream video engine 116 are provided in the accompanying text.

[0022] In some embodiments, the upstream AUX engine 114 is configured to manage AUX channel communication with the DP source device 102 and control the selective presentation of HPD signals by the upstream video engine 116. The upstream AUX engine 114 and the upstream video engine 116 can also be configured to perform link training with the DP source device 102. One of the technical challenges of extending DisplayPort communication across the extension medium 106 is that when the DP source device 102 is connected to the upstream-facing port 120, the UFP device 104 may be unaware of the presence, configuration, or capabilities of the DFP device 124 or the DP destination device 122. Furthermore, the UFP device 104 may want to establish a DisplayPort link with the DP source device 102 using the highest bandwidth supported between the DP source device 102 and the UFP device 104, regardless of the capabilities of the DP destination device 122. Therefore, to overcome these challenges, the upstream AUX engine 114 manipulates information transmitted via the AUX channel and HPD signals.

[0023] Another technical challenge arising when implementing a connection via extension medium 106 is that once link training is performed with DP source device 102, the DisplayPort link between DP source device 102 and UFP device 104 should remain active regardless of whether UFP device 104 is paired with DFP device 124, and regardless of the status of the DisplayPort link between DFP device 124 and DP destination device 122. Therefore, in some embodiments, DP destination emulation engine 110 is configured to provide information to upstream video engine 116 instead of the information typically generated by DP destination device 122 in response to signals provided by DP source device 102, to keep the link active. In this way, UFP device 104 can train and maintain the DisplayPort link with DP source device 102, and DP source device 102 will not detect any changes even if communication between UFP device 104 and DFP device 124 or between DFP device 124 and DP destination device 122 is unstable or not yet established. The following provides further details on some example technologies used by the upstream AUX engine 114, the upstream video engine 116, and the DP destination emulation engine 110 to provide this functionality.

[0024] In some embodiments, upstream video engine 116 and upstream AUX engine 114 transmit video / audio and AUX information to DFP device 124 via expansion interface 108 through expansion medium 106. In some embodiments, the expansion medium 106 and communication thereon may include any suitable networking technology, such as Ethernet, Bluetooth, WiFi, WiMAX, the Internet, serial communication, etc., and any suitable communication medium, such as via physical cable, via wireless spectrum, via fiber optic cable, etc. In some embodiments, UFP device 104 and DFP device 124 may be closer to each other than the maximum distance specified in the DisplayPort specification, but may still communicate via expansion medium 106. In some embodiments, expansion interface 108 is configured to provide physical layer connectivity and logic that allows communication via expansion medium 106. Figure 4 Further description and illustration of exemplary embodiments of the extended interface 108 are provided in the accompanying text.

[0025] exist Figure 1BThe image shows a DisplayPort sink device (DP sink device 122), a downstream-facing port device (DFP device 124), and an extension medium 106. The DP sink device 122 can be any type of device capable of acting as a DisplayPort sink as described in the DisplayPort specification. Some non-limiting examples of the DP sink device 122 include liquid crystal display (LCD) monitors, projectors, large-format screens, video processing systems, and so on. The DP sink device 122 includes a sink interface 126 that is communicatively coupled to the downstream-facing port 132 of the DFP device 124 using a cable or other connector. Similar to the connection between the DP source device 102 and the UFP device 104, the cable connecting the DFP device 124 and the DP destination device 122 (as well as the downstream-facing port 132 and the destination interface 126) may include standard DisplayPort sockets, plugs, conductors, etc. as described in the DisplayPort specification and known to those skilled in the art, or other types of sockets, plugs, conductors, etc. (including but not limited to USB-C connectors and DockPort connectors) capable of transmitting DisplayPort information.

[0026] In some embodiments, the DFP device 124 includes a downstream processor 128. Like the upstream processor 118, the downstream processor 128 and / or its components may be implemented using an FPGA, ASIC, microcontroller, and / or any other suitable type of computing device or integrated circuit. In some embodiments, the downstream processor 128 provides a downstream video engine 134 and a downstream AUX engine 130.

[0027] In some embodiments, the downstream video engine 134 is configured to receive video and / or audio signals from the expansion interface 136 and generate one or more DisplayPort channels based on these video and / or audio signals. The downstream video engine 134 is configured to provide DisplayPort channels to the DP destination device 122 via a downstream-facing port 132. The downstream video engine 134 may also be configured to receive and detect HPD signals transmitted by the DP destination device 122 via the destination interface 126. Figure 3 Further illustration and description of exemplary embodiments of the downstream video engine 134 are provided in the accompanying text.

[0028] In some embodiments, the downstream AUX engine 130 is configured to manage AUX channel communication with the DP destination device 122. This may include determining the capabilities of the DP destination device 122 to determine the maximum possible bandwidth or other connection quality. The downstream AUX engine 130 and the downstream video engine 134 may also be configured to perform link training with the DP destination device 122. In some embodiments, link training may be performed by the downstream AUX engine 130 and the downstream video engine 134 to establish a link with the highest possible bandwidth between the DFP device 124 and the DP destination device 122 based on the capabilities reported by the DP destination device 122. Further details are provided below regarding some example techniques used by the downstream AUX engine 130 and the downstream video engine 134 to provide this functionality.

[0029] In some embodiments, downstream video engine 134 and downstream AUX engine 130 communicate with upstream video engine 116 and upstream AUX engine 114 via expansion medium 106 using expansion interface 136. Expansion medium 106 has been described above, and expansion interface 136 is also similar to... Figure 1A The extended interface 108 shown is operated in reverse. Figure 4 Further description and illustration of exemplary embodiments of the extended interface 136 are provided in the accompanying text.

[0030] Figure 2 This is a block diagram illustrating a non-limiting example embodiment of an upstream video engine according to various aspects of this disclosure. As shown, the upstream video engine 116 includes a SERDES engine 202, a decoding engine 204, and a descrambling engine 206. The SERDES engine 202, or serializer / deserializer engine, is configured to deserialize parallel data streams that have been received in serial format via an upstream-facing port 120. The received data streams may include one or more scrambled and encoded video data streams. The received signals may also include AUX channel data, audio data, and / or other types of data.

[0031] Decoding engine 204 is configured to decode the encoded signal received from SERDES engine 202. The decoding algorithm to be used can be specified via AUX channel communication, allowing decoding engine 204 to be configured to use a decoding technique matching the incoming data. Some non-limiting examples of encoding formats include 8b / 10b encoding, Display Stream Compression (DSC) encoding, and so on. Descrambling engine 206 is configured to descramble the decoded video signal generated by decoding engine 204. Techniques for descrambling are described in the DisplayPort specification. The output of descrambling engine 206 (and therefore upstream video engine 116) is a video signal suitable for presentation by a video rendering device or suitable for further video processing. H.264 streaming is a non-limiting example of the output, but other suitable video formats can be used. In some embodiments, the output of upstream video engine 116 may also include audio information and / or AUX channel information.

[0032] In some embodiments, the components displayed by the upstream video engine 116 may be combined with each other, or individual components may be divided into multiple components. Some other example components suitable for use with the upstream video engine 116 are described in the description of components used to provide the main link in the DisplayPort specification.

[0033] Figure 3 This is a block diagram illustrating a non-limiting example embodiment of a downstream video engine according to various aspects of this disclosure. In some embodiments, the downstream video engine 134 provides functionality opposite to that of the upstream video engine 116. That is, the downstream video engine 134 can receive video and audio signals suitable for presentation and can transmit DisplayPort data. As shown, the downstream video engine 134 includes a scrambling engine 302, an encoding engine 304, and a SERDES engine 306. The scrambling engine 302 receives video and / or audio signals and scrambles these signals using any suitable techniques, including but not limited to those described in the DisplayPort specification. The encoding engine 304 receives the scrambled video and / or audio signals from the scrambling engine 302 and encodes these signals using any suitable techniques, including but not limited to 8b / 10b encoding, DSC encoding, etc. The SERDES engine 306 then combines the multiple scrambled and encoded data streams into a single serialized signal for transmission. Similar to the components of the upstream video engine 116, the components of the downstream video engine 134 can be combined or separated, and both their functions and structures are similar to the main link described in the DisplayPort specification.

[0034] Figure 4This is a block diagram illustrating a non-limiting example embodiment of an extended interface engine according to various aspects of this disclosure. When on a UFP device 104, the primary purpose of the extended interface engine 400 is to transmit video, audio, and / or AUX signals in an extended format via extended medium 106. When on a DFP device 124, the primary purpose of the extended interface engine 400 is to receive extended format information from extended medium 106 and convert it back to the original video, audio, and / or AUX signals. The extended interface engine 400 can also transmit information bidirectionally and can be used for connection handshakes between UFP device 104 and DFP device 124.

[0035] As shown, the extended interface engine 400 includes a multiplexing engine 402, a framing engine 404, a media access control engine (MAC engine 406), a 10 Gigabit media-independent interface engine (XGMII engine 408), an XGMII extender sublayer engine (XGXS engine 410), and a SERDES engine 412. Obtaining, implementing, and / or integrating each of these components to form the extended interface engine 400 is within the knowledge of those skilled in the art and therefore not described in detail. The extended interface engine 400, as shown, is configured to use Gigabit Ethernet as the extended medium 106. In some embodiments, the extended medium 106 may be used, and therefore components of the extended interface engine 400 will be selected as appropriate for use with different extended media.

[0036] Figure 5A and Figure 5B This is a flowchart illustrating a non-limiting example embodiment of a method for providing DisplayPort communication via an extended medium according to various aspects of this disclosure. In method 500, UFP device 104 and DFP device 124 train separate links with DP source device 102 and DP destination device 122, respectively. These links can be configured according to mismatched DisplayPort configuration data (DPCD), and UFP device 104 and DFP device 124 can compensate for the mismatch. For clarity of description, the following description of method 500 describes an embodiment in which the DisplayPort data processed includes video data but excludes audio data. However, this should not be considered a limitation: in some embodiments, method 500 can be used to process DisplayPort data that includes both video and audio data, or DisplayPort data that includes only audio data, or DisplayPort data that includes data streams other than or supplementing video and / or audio data.

[0037] From the start box, method 500 proceeds to box 502, in which a physical connection is made between the DP source device 102 and the UFP device 104. As described above, the physical connection between the DP source device 102 and the UFP device 104 can be formed by attaching a DisplayPort-compliant cable between the host interface 112 and the upstream-facing port 120.

[0038] At box 504, the DP sink emulation engine 110 of UFP device 104 performs link training with DP source device 102 using the first DisplayPort configuration data (DPCD) associated with DP source device 102. Upstream video engine 116 and upstream AUX engine 114 may also participate in the link training process. In some embodiments, the DP sink emulation engine 110 may generate EDID messages, DPCD messages, and / or DisplayID messages to be transmitted by upstream AUX engine 114 to emulate the presence of a DisplayPort sink. Otherwise, link training between DP source device 102 and UFP device 104 may occur substantially as described in the DisplayPort specification. The first DPCD may specify one or more of the following values: DPCD version, maximum link rate value, maximum channel count value, post-link training adjustment value, TPS3 support value, enhanced frame limit value, maximum downspreading value, TPS4 support value, and / or other values ​​described in Section 2.9.3.2 of the DisplayPort specification.

[0039] In some embodiments, the DP sink emulation engine 110 uses DPCD to train the link between the DP source device 102 and the UFP device 104 to have the highest possible quality supported by the DP source device 102, the UFP device 104, the extension medium 106, or a combination thereof. In some embodiments, the DP sink emulation engine 110 can train the link to the maximum bandwidth, bit depth, refresh rate, resolution, and / or timing supported by the DP source device 102.

[0040] At box 506, a physical connection is made between DP sink device 122 and DFP device 124. Similar to the physical connection between DP source device 102 and UFP device 104, the physical connection between DP sink device 122 and DFP device 124 can be formed as described above by attaching a DisplayPort-compliant cable between downstream port 132 and sink interface 126.

[0041] At block 508, the downstream video engine 134 of DFP device 124 uses a second DPCD associated with DP destination device 122 to perform link training with DP destination device 122. In some embodiments, the downstream AUX engine 130 may also participate in the link training process. In some embodiments, the downstream video engine 134 may request EDID, DPCD, and / or DisplayID information from DP destination device 122, and may train the link between DFP device 124 and DP destination device 122 with the maximum bandwidth, maximum resolution, maximum bit depth, maximum refresh rate, and / or fastest timing supported by DP destination device 122, physical connection, DFP device 124, extension medium 106, and / or a combination thereof. Similar to the first DPCD, the second DPCD may specify one or more of the following values: DPCD version, maximum link rate value, maximum channel count value, post-link training adjustment value, TPS3 support value, enhanced frame limit value, maximum downspreading value, TPS4 support value, and / or other values ​​described in Section 2.9.3.2 of the DisplayPort specification.

[0042] In some embodiments, one or more of the following may differ between the first DPCD and the second DPCD: DPCD version, maximum link rate value, maximum channel count value, post-link training adjustment value, enhanced frame limit value, and / or maximum downspreading value. Video data extracted by the UFP device 104 and DisplayPort data including video data generated by the DFP device 124 can be used to compensate for the differences between the first DPCD and the second DPCD.

[0043] At box 510, UFP device 104 begins receiving DisplayPort data from DP source device 102 as specified by the first DPCD. The DisplayPort data includes video data generated by DP source device 102 with bandwidth / timing negotiated during link training between UFP device 104 and DP source device 102.

[0044] Method 500 then proceeds to the continuation terminal (“Terminal A”). From Terminal A ( Figure 5BMethod 500 proceeds to block 512, in which UFP device 104 extracts video data from DisplayPort data received from DP source device 102. In some embodiments, upstream video engine 116 of UFP device 104 receives DisplayPort data from DP source device 102 via SERDES engine 202. SERDES engine 202 provides the deserialized DisplayPort data to decoding engine 204, which decodes the DisplayPort data. The decoded DisplayPort data is provided to descrambling engine 206, which descrambles the decoded DisplayPort data to obtain video data.

[0045] At block 514, UFP device 104 transmits video data to DFP device 124 via extension medium 106. In some embodiments, upstream video engine 116 provides video data to extension interface engine 400, which passes the video data through multiplexing engine 402, framing engine 404, MAC engine 406, XGMII engine 408, XGXS engine 410, and SERDES engine 412 to prepare the video data for transmission via extension medium 106.

[0046] At block 516, DFP device 124 receives video data via an extended medium. In some embodiments, the extended interface engine 400 of DFP device 124 receives the data and processes it via SERDES engine 412, XGXS engine 410, XGMII engine 408, MAC engine 406, framing engine 404, and multiplexing engine 402 to reconstruct video data from the data transmitted across the extended medium 106.

[0047] At block 518, DFP device 124 generates DisplayPort data including video data as specified by the second DPCD. In some embodiments, the scrambling engine 302, encoding engine 304, and SERDES engine 306 of the downstream video engine 134 are used to generate DisplayPort data including video data and having the number of channels, resolution, bit depth, refresh rate, timing, and any other characteristics of a second bandwidth link trained between DP sink device 122 and DFP device 124. At block 520, DFP device 124 transmits DisplayPort data as specified by the second DPCD to DP sink device 122.

[0048] As shown, method 500 then proceeds to the end box and terminates. Although shown as ending at this point for clarity, DP source device 102 typically continues to transmit DisplayPort data to UFP device 104, which continues to extract video data and transmit it to DFP device 124, and DFP device 124 continues to generate DisplayPort data including the video data and transmit it to DP destination device 122.

[0049] In some embodiments, the link between DP source device 102 and UFP device 104, the link between DFP device 124 and DP destination device 122, or both, may be retrained to different bandwidths at some point during data transmission. In such embodiments, the operation of UFP device 104 and DFP device 124 should continue seamlessly because the first and second bandwidths do not need to match at any time. At most, if the link between DFP device 124 and DP destination device 122 is retrained to a third bandwidth, DFP device 124 will generate more DisplayPort data at the third bandwidth instead of the second bandwidth, and DP source device 102 and UFP device 104 will not require any reconfiguration or link retraining.

[0050] Although illustrative embodiments have been shown and described, it will be appreciated that various changes may be made therein without departing from the spirit and scope of the invention.

Claims

1. A system for providing DisplayPort communication via an extended medium, the system comprising: Extended media; Upstream-facing port device (UFP device) that is communicatively coupled to the DisplayPort source device and the extension medium; as well as Downstream-facing port device (DFP device) that is communicatively coupled to the DisplayPort sink device and the extension medium; The UFP device is configured as follows: Link training is performed using the first DisplayPort configuration data (DPCD) associated with the DisplayPort source device. Receive DisplayPort data as specified by the first DPCD from the DisplayPort source device; Extract video data from DisplayPort data received from the DisplayPort source device; and The video data is transmitted to the DFP device via the extended medium; and The DFP device is configured as follows: Link training is performed using a second DisplayPort configuration data (DPCD) associated with the DisplayPort destination device. Receive the video data from the UFP device; Generate DisplayPort data as specified by the second DPCD, wherein the generated DisplayPort data includes the video data; and The generated DisplayPort data, as specified by the second DPCD, is transmitted to the DisplayPort destination device. The first DPCD is different from the second DPCD.

2. The system as claimed in claim 1, wherein, The first DPCD specifies a first maximum channel count value, and the second DPCD specifies a second maximum channel count value that is different from the first maximum channel count value.

3. The system as described in claim 1, wherein, The first DPCD specifies a first TPS3 supported value, and the second DPCD specifies a second TPS3 supported value that is different from the first TPS3 supported value, or Wherein, the first DPCD specifies a first TPS4 supported value, and wherein the second DPCD specifies a second TPS4 supported value that is different from the first TPS4 supported value.

4. The system as claimed in claim 1, wherein, The first DPCD specifies a first DPCD version, and the second DPCD specifies a second DPCD version that is different from the first DPCD version.

5. The system as claimed in claim 1, wherein, The first DPCD specifies a first maximum link rate value, and the second DPCD specifies a second maximum link rate value that is different from the first maximum link rate value.

6. The system of claim 1, wherein, The first DPCD specifies the adjustment value after training the first link, and the second DPCD specifies the adjustment value after training the second link, which is different from the adjustment value after training the first link.

7. The system as claimed in claim 1, wherein, The first DPCD specifies a first enhanced frame upper limit value, and the second DPCD specifies a second enhanced frame upper limit value that is different from the first enhanced frame upper limit value.

8. The system as claimed in claim 1, wherein, The first DPCD specifies a first maximum downspreading value, and the second DPCD specifies a second maximum downspreading value that is different from the first maximum downspreading value.

9. The system as claimed in claim 1, wherein, The UFP device includes an upstream-facing USB-C port, and the UFP device is communicatively coupled to the DisplayPort source device via the upstream-facing USB-C port.

10. The system of claim 1, wherein, The UFP device includes a DisplayPort socket, and wherein the UFP device is communicatively coupled to the DisplayPort source device via the DisplayPort socket.

11. The system of claim 1, wherein, The DFP device includes a downstream-facing USB-C port, and wherein the DFP device is communicatively coupled to the DisplayPort receiver device via the downstream-facing USB-C port.

12. The system of claim 1, wherein, The DFP device includes a DisplayPort socket, and wherein the DFP device is communicatively coupled to the DisplayPort receiver device via the DisplayPort socket.

13. The system of claim 1, wherein, Extracting video data from DisplayPort data received from the DisplayPort source device includes: The UFP device decodes and descrambles the encoded scrambled video from the DisplayPort data.

14. The system of claim 1, wherein, Generating DisplayPort data, including the video data, as specified by the second DPCD, includes: The DFP device encodes and scrambles the video data to generate the DisplayPort data.

15. The system of claim 1, further comprising: A first cable that communicatively couples the UFP device to the DisplayPort source device; as well as A second cable that communicatively couples the DFP device to the DisplayPort receiver device; Both the first cable and the second cable support communication conforming to at least one DisplayPort standard.

16. A downstream-facing port device (DFP device), comprising: A first interface, configured to be communicatively coupled to an extension medium; A second interface, configured to be communicatively coupled to a DisplayPort receiver device; as well as The response is executed by the DFP device, causing the DFP device to perform actions including the following: Link training is performed using the first DisplayPort configuration data (DPCD) and the DisplayPort destination device, wherein the first DPCD is associated with the DisplayPort destination device; Video data is received via the first interface, wherein the video data is extracted from DisplayPort data received from an upstream port device (UFP device) via a link trained using second DisplayPort configuration data (DPCD); Generate DisplayPort data as specified by the first DPCD, wherein the generated DisplayPort data includes the video data; and The DisplayPort data, as specified by the first DPCD, is transmitted to the DisplayPort destination device. The first DPCD is different from the second DPCD.

17. The downstream-facing port device as described in claim 16, wherein, The first DPCD and the second DPCD specify one or more different configuration settings, wherein the one or more different configuration settings include one or more of the following: DPCD version; Maximum link rate value; Maximum channel count value; Adjustment values ​​after link training; TPS3 supported values, Increase the frame rate cap; Maximum downward spread spectrum value; and TPS4 supported values.

18. The downstream-facing port device as described in claim 16, wherein, The second interface includes at least one of a downstream-facing USB Type-C port and a DisplayPort socket.

19. A non-transitory computer-readable medium storing computer-executable instructions that, in response to execution by a downstream-facing port device (DFP device), cause the DFP device to perform actions including: Link training is performed using the first DisplayPort configuration data (DPCD) and the DisplayPort destination device, where, The first DPCD is associated with the DisplayPort receiver device; Video data is received from the extended interface, wherein the video data is extracted from DisplayPort data received from the upstream port device (UFP device) via a link trained using the second DisplayPort configuration data (DPCD); Generate DisplayPort data as specified by the first DPCD, wherein the generated DisplayPort data includes the video data; and The DisplayPort data, as specified by the first DPCD, is transmitted to the DisplayPort destination device. The first DPCD is different from the second DPCD.

20. The non-transitory computer-readable medium of claim 19, wherein, The first DPCD and the second DPCD specify one or more different configuration settings, wherein the one or more different configuration settings include one or more of the following: DPCD version; Maximum link rate value; Maximum channel count value; Adjustment values ​​after link training; TPS3 supported values; Increase the frame rate cap; Maximum downward spread spectrum value; and TPS4 supported values.

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