Patent Grant
11314310
Embodiments described herein generally relate to refreshing display panels and particularly to refreshing images displayed on panels with partial and full frame updates.
Display panels include memory that stores, for each pixel, the color to be displayed. Pixel memory retention times are on the order of tens to hundreds of milliseconds. However, an image may remain on the screen for viewing over an extended viewing period on the order of tens or hundreds of seconds, if not minutes. Thus, the pixel memory is periodically refreshed at what is known as a refresh rate.
Modern display panels typically include frame buffers, which are integrated into the display panel and provide memory retention to allow for the panel to “self-refresh.” Self-refresh techniques provide a significant boost to energy efficiency of display devices.
The present disclosure is generally directed to optimizing display device self-refresh modes based on full frame idle images, new full frame updates and partial frame updates. Self-refresh techniques can provide for savings in power consumption, particularly when dealing with full frame idle images. However, display image updates are not always full images and often, the image update intervals are not synchronized with frame update intervals. For example, a user's interaction with a display system is arbitrary and not often synchronized with frame update intervals. Thus, display panels are required to continuously monitor for image (both full and partial) updates, which can erode the power reduction benefits of these self-refresh techniques.
Provided herein are systems, display panel and source circuitry, and techniques to provide notification to display modules of the transitions between full frame idle images, new full frame updates and partial frame updates. This disclosure provides advantages over prior techniques in that power optimizations (e.g., power management of unused display electronics and/or circuitry, reducing refresh rate in the display module, etc.) can be implemented without relying on control from image source circuitry. This provides a latent advantage in that suppliers can independently test features (e.g., refresh rate changes, etc.) and therefore make product line decisions without being tightly coupled with image source circuitry suppliers.
Various embodiments may comprise one or more elements. An element may comprise any structure arranged to perform certain operations. Each element may be implemented as hardware, software, or any combination thereof, as desired for a given set of design parameters or performance constraints. Although an embodiment may be described with a limited number of elements in a certain topology by way of example, the embodiment may include more or less elements in alternate topologies as desired for a given implementation. It is worthy to note that any reference to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. The appearances of the phrases “in one embodiment,” “in some embodiments,” and “in various embodiments” in various places in the specification are not necessarily all referring to the same embodiment.
The platform 10 may have a processing unit 12, which can be a conventional processor, a graphics processing unit (GPU) or a combination of conventional processor and GPU. Platform 10 further includes a transmitter 14. Processor 12 and transmitter 14 may constitutes a display engine. Platform 10 may be provided as a System-on-Chip (SoC), such as may be integrated into a display system device (e.g., mobile phone, laptop, portable media device, etc.). In general, platform 10 sends images for display by panel 10 via display interface 16. For example, platform 10 can send, via transmitter 14 and display interface 16, information elements including indications of pixel data (e.g., color, locations, etc.) generated by GPU 12 to panel 18. Such information elements (or “frames”) often sent at intervals corresponding to a frame rate of panel 18. This is described in greater detail below.
Panel 18 may include a receiver 20, panel registers 22, panel buffers 24, timer 26, display controller 28 and display electronics 30. In general, panel 18 can receive frames (e.g., from platform) at receiver 20 via display interface 16. Receiver 20 can provide the frames to display controller 28, which in turn, provides the frames for display on display electronics 28. Receiver 20 and/or display electronics may have access to panel registers 22, which may store indications of settings for panel 18 (e.g., refresh rate, etc.). Timer 24 can be coupled to receiver 20 and/or display controller 28 and can operate to provide an expiration of a frame refresh interval, or expiation of a period where the display interface 16 link is shut down to conserve power, for example, when the panel 18 is operating in a self-refresh mode, sometimes referred to as panel self-refresh (PSR).
Panel buffer 24 provides memory storage for frames received via display interface 16. Display controller 28 can operate to shut down portions of panel (e.g., receiver, or the like) during periods of PSR and can refresh display electronics from indications of the frame stored in panel buffers 24.
During operation, the transmitter 14 and receiver 20 can be arranged to coordinate PSR and/or shutting down display interface 16. As provided herein, such coordination can include coordinating frame updates between the source (e.g., platform 10) and the sink (e.g., panel 18).
The frame update schedule 200 depicts typical streaming of frames from a source (e.g., platform 10) to a sink (e.g., panel 18) without panel self-refresh.
Schedule 300, like schedule 200, includes VB intervals 210 disposed between frames 220. However, as depicted, schedule 300 includes a PSR interval 330 and a retraining interval 340. In general, schedule 300 can provide a full frame update for frame 220-2. Panel 18 can store frame N+1 for PSR interval. For example, panel buffers 24 can store frame N+1, which display controller 28 can use to refresh display electronics 30 during PSR interval 330. Additionally, schedule 300 includes a partial PSR interval PSR 330′. PSR 330′ could correspond to a selective update process, for example, to update partial frame N′.
Panel 18 can be arranged to resynchronize with platform 10 during retraining intervals 340. Said differently, receiver 20 and/or display controller 28 can be powered up and remain in full frame update mode for a selected number of frames (e.g., as specified in panel registers 22, or the like) before resuming with power management functions such as PSR 330 or PSR_2330′. Furthermore, receiver and/or display controller 28 can be arranged to power down for a selected number of frames (e.g., as specified in panel registered 22, or the like) during PSR 300 or PSR_2330′.
Platform 10 can provide a regular, or single frame update, at block 420. Subsequently, platform 10 can request or initiate PSR at block 430. Specifically, at block 430, the platform can indicate to the panel that stable frame data is expected. In response, the panel 18 can enter PSR at block 440. For example, the panel 18 can shut down the link 16 and/or other electronics within the panel, such as, for example, the receiver 20. It is important to note, that the PSR is enabled in response to the platform indicating stable frame data is expected. This is different than conventional system where the panel determines that stable frames have been received and enters PSR.
At block 450, the panel 18 can exit PSR and retrain the link 16. In some examples, the panel 18 can stay in PSR for a selected number of frames (e.g., 2 frames in this example). Upon exiting from PSR, panel 18 may be required to remain in full, or regular, frame update mode for a selected number of frames. This number of frames can be specified, for example, within panel registers, or the like.
In general, the platform 10 can indicate to the panel 18 that no frame updates (full, partial, etc.) are expected using any of a variety of techniques. In response, the panel 18 can enter PSR and apply power management functions (e.g., clock gating components within the panel 18, applying selective refresh rate reduction, etc.).
With some examples, the platform 10 can indicate to the panel 18 that no frame updates are expected via a sideband interconnect or side band interface. For example, in many applications link 16 may include side band channels that couple platform 10 and panel 18. Platform 10 could send an indication (e.g., a control signal, an information element, or the like) via this side band channel. As a specific example, platform 10 can indicate to panel via a level-sensitive or edge-sensitive side band channel in link 16 that no frame updates are expected.
In some examples, the platform 10 can indicate to the panel 18 that no frame updates are expected via an existing configuration channel within link 16. For example, display port links include an AUX channel, which the platform 10 could use to indicate (e.g., via a control signal, via an information element, or the like) to the panel 18 that no frame updates are expected.
With some examples, the platform 10 can indicate to the panel 18 that no frame updates are expected by tagging an indicator onto a packet sent between the platform 10 and the panel 18 via link 16. For example, platform 10 may append a selected character or symbol onto a packet at each frame boundary to indicate to the panel 18 whether future frame updates are expected. In response, panel 18 may determine whether to enter PSR as discussed herein. As a specific example, platform 10 can employ the secondary data packet mechanism provided by the Embedded Display Port (eDP) Standard v 1.4, published in February 2015 and promulgated by the Video Electronics Standards Association (VESA) to indicate to the panel that no frame updates are expected.
At block 520 “denote a full or partial frame update” a full or partial frame update can be denoted. For example, platform 10 can denote a full frame update to panel 18 where the new content includes an entirely new frame. Similarly, platform 10 can denote a partial frame update to panel 18 where the new content includes partial frame updates. At decision block 525 “idle duration threshold reached?” platform 10 can determine whether an idle duration threshold has been reached. Said differently, platform 10 can determine whether no new content (e.g., based on decision block 515) has been received in a selected period of time (e.g., 1 frame, 2 frames, 3 frames, 4 frames, etc.).
From block 520, logic flow 500 can continue to decision block 535. At decision block 535 “threshold to maintain sync satisfied?” platform 10 can determine whether a sync maintenance threshold has been reached. For example, in some implementations (e.g., as indicated in
From decision block 535, logic flow 500 can return to either block 510 or decision block 515. For example, logic flow 500 can continue from decision block 535 to block 510 based on a determination that the sync maintenance threshold has not been reached. Conversely, logic flow 500 can continue from decision block 535 to decision block 515 based on a determination that the sync maintenance threshold has been reached.
From decision block 525, logic flow 500 can either return to decision block 515 or continue to block 530. For example, logic flow 500 can continue from decision block 525 to block 530 based on a determination that idle duration threshold has been met. Conversely, logic flow 500 can proceed from decision block 525 to decision block 515 based on a determination that the idle duration threshold has not been met.
At block 530 “denote no new or partial frame updates” platform 10 can indicate that no new or partial frame updates are expected. For example, platform 10 can send an indication to panel 18 (e.g., via a sideband channel, via an out of band channel, via an in-band channel, via appending a character to a frame, or the like) that no new frame updates are expected.
Continuing to block 540 “wait for new content or idle link threshold expiration” platform 10 can wait for new content or an idle link threshold to expire. For example, platform 10 can determine at block 540 that new content (e.g., full frame or partial frame update) has been received. Additionally, at block 540, platform 10 can determine that an idle link threshold duration has expired. For example, in some embodiments, the platform 10 and the panel 18 may be arranged to coordinate an idle link period (e.g., 2 frames, 3 frames, 4 frames, or the like) in which once the platform 10 send an indication that no frame updates are expected, the platform 10 will send a new update at the expiration of this known idle link threshold. As such, coordination between the platform 10 and the panel 18 as to when updates will be sent once PSR has been initiated can be achieved. This idle link threshold can be programmed at initialization, for example, within panel registers 22, or the like.
Continuing from block 540 to block 550 “send a full frame to the panel” the platform 10 can send a full frame update to the panel 18. Continuing to decision block 555 “duration for timing resync reached?” the platform 10 can determine whether a timing resynchronization duration has been reached. For example, in some implementations, the platform 10 and panel 18 need to exchange a set number of full frames to resynchronize timing between controllers. At decision block 555, platform 10 can determine whether this period has been reached. From decision block 555, logic flow 500 can return to either block 550 or block 510. For example, logic flow 500 can continue from decision block 555 to block 510 based on a determination that the duration for timing resync has been reached. Conversely, logic flow 500 can continue from decision block 555 to block 550 based on a determination that the duration for timing resync has not been reached.
Examples of a computer readable or machine readable storage medium may include any tangible media capable of storing electronic data, including volatile memory or non-volatile memory, removable or non-removable memory, erasable or non-erasable memory, writeable or re-writeable memory, and so forth. Examples of computer executable instructions may include any suitable type of code, such as source code, compiled code, interpreted code, executable code, static code, dynamic code, object-oriented code, visual code, and the like. The examples are not limited in this context.
As depicted, I/O device 3006, RAM 3008, and ROM 3010 are coupled to processor 3002 by way of chipset 3004. Chipset 3004 may be coupled to processor 3002 by a bus 3012. Accordingly, bus 3012 may include multiple lines.
Processor 3002 may be a central processing unit comprising one or more processor cores and may include any number of processors having any number of processor cores. The processor 3002 may include any type of processing unit, such as, for example, CPU, multi-processing unit, a reduced instruction set computer (RISC), a processor that has a pipeline, a complex instruction set computer (CISC), digital signal processor (DSP), and so forth. In some embodiments, processor 3002 may be multiple separate processors located on separate integrated circuit chips. In some embodiments processor 3002 may be a processor having integrated graphics, while in other embodiments processor 3002 may be a graphics core or cores.
Some embodiments may be described using the expression “one embodiment” or “an embodiment” along with their derivatives. These terms mean that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. The appearances of the phrase “in one embodiment” in various places in the specification are not necessarily all referring to the same embodiment. Further, some embodiments may be described using the expression “coupled” and “connected” along with their derivatives. These terms are not necessarily intended as synonyms for each other. For example, some embodiments may be described using the terms “connected” and/or “coupled” to indicate that two or more elements are in direct physical or electrical contact with each other. The term “coupled,” however, may also mean that two or more elements are not in direct contact with each other, but yet still co-operate or interact with each other. Furthermore, aspects or elements from different embodiments may be combined.
It is emphasized that the Abstract of the Disclosure is provided to allow a reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. In addition, in the foregoing Detailed Description, it can be seen that various features are grouped together in a single embodiment for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed embodiments require more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive subject matter lies in less than all features of a single disclosed embodiment. Thus the following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separate embodiment. In the appended claims, the terms “including” and “in which” are used as the Plain-English equivalents of the respective terms “comprising” and “wherein,” respectively. Moreover, the terms “first,” “second,” “third,” and so forth, are used merely as labels, and are not intended to impose numerical requirements on their objects.
What has been described above includes examples of the disclosed architecture. It is, of course, not possible to describe every conceivable combination of components and/or methodologies, but one of ordinary skill in the art may recognize that many further combinations and permutations are possible. Accordingly, the novel architecture is intended to embrace all such alterations, modifications and variations that fall within the spirit and scope of the appended claims. The detailed disclosure now turns to providing examples that pertain to further embodiments. The examples provided below are not intended to be limiting.
An apparatus, comprising: a transmitter to send a frame to a panel via a display interconnect; and a processor coupled to the transmitter, the processor to: determine to initiate power management functions within the panel; and cause the transmitter to send an indication to the panel to cause the panel to initiate power management functions.
The apparatus of example 1, the processor to: determine whether a full or a partial frame update is to be sent to the panel; determine to initiate power management functions within the panel based on a determination that a full or a partial frame update is not to be sent to the panel.
The apparatus of example 2, the processor to: determine whether an idle duration threshold has been met; and determine to initiate power management functions within the panel based on a determination that an idle duration threshold has been met.
The apparatus of example 1, the transmitter coupled to the panel via a sideband channel, the transmitter to send a control signal to the panel via the sideband channel, the control signal to cause the panel to initiate power management functions.
The apparatus of example 1, the transmitter to send a control signal to the panel via an auxiliary channel within the display interconnect, the control signal to cause the panel to initiate power management functions.
The apparatus of example 1, the processor to append a character onto a frame to be sent, by the transmitter, to the panel, the character to indicate to the panel to initiate power management functions.
The apparatus of example 6, the processor to append the character onto the frame in accordance with the secondary data packet mechanism provided by the Embedded Display Port (eDP) Standard v 1.4, published in February 2015 and promulgated by the Video Electronics Standards Association (VESA).
The apparatus of example 1, comprising a display interface coupled to the transmitter, the display interface to couple to the display interconnect.
The apparatus of example 8, the display interface comprising a display port interface or an embedded display port interface.
A method comprising: determining, by a processor in a platform coupled to a panel via a display interconnect, to initiate power management functions within a panel; and sending, from the transmitter, an indication to the panel to cause the panel to initiate power management functions.
The method of example 10, comprising: determining whether a full or a partial frame update is to be sent to the panel; determining to initiate power management functions within the panel based on a determination that a full or a partial frame update is not to be sent to the panel.
The method of example 11, comprising: determining whether an idle duration threshold has been met; and determining to initiate power management functions within the panel based on a determination that an idle duration threshold has been met.
The method of example 10, the transmitter coupled to the panel via a sideband channel, the method comprising sending, by the transmitter, a control signal to the panel via the sideband channel, the control signal to cause the panel to initiate power management functions.
The method of example 10, comprising sending, by the transmitter, a control signal to the panel via an auxiliary channel within the display interconnect, the control signal to cause the panel to initiate power management functions.
The method of example 10, comprising appending, by the processor, a character onto a frame to be sent by the transmitter to the panel, the character to indicate to the panel to initiate power management functions.
The method of example 15, comprising appending the character onto the frame in accordance with the secondary data packet mechanism provided by the Embedded Display Port (eDP) Standard v 1.4, published in February 2015 and promulgated by the Video Electronics Standards Association (VESA).
The method of example 10, the display interconnect comprising a display port interconnect or an embedded display port interconnect.
At least one machine-readable storage medium comprising instructions that when executed by a processor at a platform coupled to a panel via a display interconnect, cause the processor to: determine to initiate power management functions within a panel; and cause a transmitter to send to the panel, via the display interconnect, an indication to the panel to cause the panel to initiate power management functions.
The at least one machine-readable storage medium of example 18, comprising instructions that further cause the processor to: determine whether a full or a partial frame update is to be sent to the panel; determine to initiate power management functions within the panel based on a determination that a full or a partial frame update is not to be sent to the panel.
The at least one machine-readable storage medium of example 19, comprising instructions that further cause the processor to: determine whether an idle duration threshold has been met; and determine to initiate power management functions within the panel based on a determination that an idle duration threshold has been met.
The at least one machine-readable storage medium of example 18, comprising instructions that further cause the processor to cause the transmitter to send a control signal to the panel via a sideband channel, the control signal to cause the panel to initiate power management functions, the transmitter coupled to the panel via the sideband channel.
The at least one machine-readable storage medium of example 18, comprising instructions that further cause the processor to cause the transmitter to send a control signal to the panel via an auxiliary channel within the display interconnect, the control signal to cause the panel to initiate power management functions.
The at least one machine-readable storage medium of example 18, comprising instructions that further cause the processor to append a character onto a frame to be sent by the transmitter to the panel, the character to indicate to the panel to initiate power management functions.
The at least one machine-readable storage medium of example 23, comprising instructions that further cause the processor to append the character onto the frame in accordance with the secondary data packet mechanism provided by the Embedded Display Port (eDP) Standard v 1.4, published in February 2015 and promulgated by the Video Electronics Standards Association (VESA).
The at least one machine-readable storage medium of example 18, the display interconnect comprising a display port interconnect or an embedded display port interconnect.
An apparatus, comprising: a receiver, at a panel, to receive a frame from a platform via a display interconnect; and a processor coupled to the receiver, the processor to: receive a control signal, from the platform, including an indication to initiate power management functions at the panel; and cause power management functions to be initiated.
The apparatus of example 26, the receiver coupled to the platform via a sideband channel, the receiver to receive the control signal via the sideband channel.
The apparatus of example 26, the receiver to receive the control signal via an auxiliary channel within the display interconnect.
The apparatus of example 26, the control signal comprising a frame including a character appended onto the frame, the character to indicate to the panel to initiate power management functions.
The apparatus of example 29, the character appended onto the frame in accordance with the secondary data packet mechanism provided by the Embedded Display Port (eDP) Standard v 1.4, published in February 2015 and promulgated by the Video Electronics Standards Association (VESA).
The apparatus of example 26, comprising a display interface coupled to the receiver, the display interface to couple to the display interconnect.
The apparatus of example 31, the display interface comprising a display port interface or an embedded display port interface.
A method comprising: receiving a control signal, from the platform, including an indication to initiate power management functions at the panel; and causing power management functions to be initiated.
The method of example 33, the receiver coupled to the platform via a sideband channel, the method comprising receiving the control signal via the sideband channel.
The method of example 33, comprising receiving the control signal via an auxiliary channel within the display interconnect.
The method of example 33, the control signal comprising a frame including a character appended onto the frame, the character to indicate to the panel to initiate power management functions.
The method of example 36, the character appended onto the frame in accordance with the secondary data packet mechanism provided by the Embedded Display Port (eDP) Standard v 1.4, published in February 2015 and promulgated by the Video Electronics Standards Association (VESA).
The method of example 33, the display interface comprising a display port interface or an embedded display port interface.
At least one machine-readable storage medium comprising instructions that when executed by a processor at a panel coupled to a platform via a display interconnect, cause the processor to: receive a control signal, from the platform, including an indication to initiate power management functions at the panel; and cause power management functions to be initiated.
The at least one machine-readable storage medium of example 39, the receiver coupled to the platform via a sideband channel, the at least medium comprising instructions that further cause the processor to receive the control signal via the sideband channel.
The at least one machine-readable storage medium of example 39, comprising instructions that further cause the processor to receive the control signal via an auxiliary channel within the display interconnect.
The at least one machine-readable storage medium of example 39, the control signal comprising a frame including a character appended onto the frame, the character to indicate to the panel to initiate power management functions.
The at least one machine-readable storage medium of example 42, the character appended onto the frame in accordance with the secondary data packet mechanism provided by the Embedded Display Port (eDP) Standard v 1.4, published in February 2015 and promulgated by the Video Electronics Standards Association (VESA).
The at least one machine-readable storage medium of example 39, the display interface comprising a display port interface or an embedded display port interface.
An apparatus comprising: means, in a platform coupled to a panel via a display interconnect, to determine to initiate power management functions within a panel; and means to send, from the transmitter, an indication to the panel to cause the panel to initiate power management functions.
The apparatus of example 45, comprising: means to determine whether a full or a partial frame update is to be sent to the panel; means to determine to initiate power management functions within the panel based on a determination that a full or a partial frame update is not to be sent to the panel.
The apparatus of example 46, comprising: means to determine whether an idle duration threshold has been met; and means to determine to initiate power management functions within the panel based on a determination that an idle duration threshold has been met.
The apparatus of example 45, the panel coupled to the platform via a sideband channel, the apparatus comprising means to send a control signal to the panel via the sideband channel, the control signal to cause the panel to initiate power management functions.
The apparatus of example 45, comprising means to send a control signal to the panel via an auxiliary channel within the display interconnect, the control signal to cause the panel to initiate power management functions.
The apparatus of example 45, comprising means to append a character onto a frame to be sent by the transmitter to the panel, the character to indicate to the panel to initiate power management functions.
The apparatus of example 50, comprising means to append the character onto the frame in accordance with the secondary data packet mechanism provided by the Embedded Display Port (eDP) Standard v 1.4, published in February 2015 and promulgated by the Video Electronics Standards Association (VESA).
The apparatus of example 45, the display interconnect comprising a display port interconnect or an embedded display port interconnect.
An apparatus comprising: means, at a panel, to receive a control signal from a platform, the control signal including an indication to initiate power management functions at the panel; and means to cause power management functions to be initiated.
The apparatus of example 53, the panel coupled to the platform via a sideband channel, the apparatus comprising means to receive the control signal via the sideband channel.
The apparatus of example 53, comprising means to receive the control signal via an auxiliary channel within the display interconnect.
The apparatus of example 53, the control signal comprising a frame including a character appended onto the frame, the character to indicate to the panel to initiate power management functions.
The apparatus of example 36, the character appended onto the frame in accordance with the secondary data packet mechanism provided by the Embedded Display Port (eDP) Standard v 1.4, published in February 2015 and promulgated by the Video Electronics Standards Association (VESA).
The apparatus of example 33, the display interface comprising a display port interface or an embedded display port interface.
A system comprising: the apparatus of any one of examples 1 to 10; and the apparatus of any one of examples 26 to 32.
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