Patent Application
20080104126
This invention relates generally to mobile devices, and more particularly to a reduced power system and methods for sharing data between multiple processors in a mobile device.
As mobile devices become more advanced by providing multimedia features, such as audio and video playback, the tendency of such systems is to require additional power to efficiently operate the mobile device. However, even though users desire that the capabilities of advanced mobile devices increase, at the same time they require that such devices be more energy efficient and provide longer battery life. Additionally, it is not desired that the size of the mobile device increase to allow a larger battery, instead, users desire smaller devices with longer battery lifetime.
Advanced mobile devices require additional power since the tasks required for the mobile device to operate are generally divided among several different types of processors, including a multimedia accelerator and a baseband processor or application processor. Power consumption is also further increased when the mobile device incorporates a storage device which the multiple processors need to access efficiently. The main problem in such systems is that the several processors generally cannot share file systems and storage devices efficiently. However, there are several known methods of providing file sharing capabilities among multiple processors, but each having limitations.
A first known method utilizes a file system running on an application processor, but with the storage device being directly coupled to a multimedia processor, as shown in
A second known method utilizes a file system running on an application processor and with a storage device being also directly coupled to an application processor, as shown in
A third known method utilizes a file system running on a multimedia processor and a storage device is also connected to the multimedia processor as shown in
As described above, systems and methods to provide efficient file sharing between multimedia processors and application processors do not exist. Current designs available to provide this functionality suffer from two main drawbacks: (1) power consumption is higher, since the two systems must operate at the same time during file sharing, and (2) data must be often transferred from a first processor to second processor, only to have to transfer the data back to the first processor, thereby increasing not only power consumption, but port bandwidth requirements. Therefore, a method or system for sharing multimedia data processing on a mobile device that allows data on a storage device coupled to a processor or a file system of a processor to be shared among multiple processors, including a multimedia processor, while minimizing power consumption is lacking in the marketplace.
Embodiments in accordance with the present invention can provide a pass-thru multimedia processor system and methods that provide for file sharing between the multimedia processor and an application or baseband processor configured to optimize battery life of a mobile device.
In a first embodiment, a multimedia processor system for a mobile device can include a central processing unit (CPU), a system bus port accessible by the CPU, a virtual file system (VFS) accessible by the CPU where the VFS is synchronized with a remote file system of a remote application processor coupled to the system bus port, at least one storage device port accessible by the CPU, and at least one storage device pass-thru port coupled to the at least one storage device port by a pass-thru controller managed by the CPU, where the CPU instructs the pass-thru controller to disable access of the at least one pass-thru port to the at least one storage device port. The multimedia processor can be further configured to be active only during multimedia events and dormant during other events on the mobile device. The multimedia processor can also be configured to automatically enable the pass-thru ports when the CPU is dormant. The multimedia processor can also be further configured to be able to process an incoming multimedia stream and record the stream directly to a mass storage device without intervention from the applications processor.
In a second embodiment of the invention, a method for processing data with a multimedia processor with a pass-thru architecture can include the steps of disabling at least one pass-thru port by instructing a data pass-thru controller to decouple at least one storage device port from at least one external pass-thru port, accessing at least one data source connected to at least one storage device port, retrieving data from at least one data source (where at least a portion of the retrieved data comprises multimedia data), storing the data in a virtual file system of the multimedia processor (where the virtual file system of the multimedia processor is synchronized with a remote file system of a remote applications processor), and processing the data stored in the virtual file system. The method can further include the steps of processing data while the applications processor is dormant. The method can also include recording multimedia data from a data source onto a mass storage device. The method can further include buffering data for an applications processor and reviving an applications processor when buffered data needs to be processed. The method can also include allowing the applications processor to access a data source not currently being used by the multimedia processor.
In a third embodiment of the present invention, a method for externally retrieving data from a data source coupled to a multimedia processor with a pass-thru architecture can include the steps of coupling at least one pass-thru port of a multimedia processor to at least one storage device port of a remote processor (where at least one pass-thru port is coupled to at least one storage device port of the multimedia processor), accessing a data source connected to at least one storage device port of the multimedia processor, retrieving data from the data source, and transferring the retrieved data to a remote file system of the remote processor (where the virtual file system of the multimedia processor is synchronized with a remote file system of a remote applications processor). The method can further include the step of enabling at least one pass-thru port where at least one pass-thru port is coupled to at least to at least one storage device port of the multimedia processor by a pass-thru controller managed by the multimedia processor. The method can also include automatically enabling a pass-thru port when the multimedia processor is dormant.
Embodiments in accordance with the invention disclosed herein provide a method and a system for sharing of a file system between a multimedia processor or accelerator and a baseband processor or application processor in a mobile device. Additionally embodiments herein provide for lower power consumption in a multiple processor system and increased bandwidth due to lower amounts of data transferred between a multimedia processor and an application processor. Additionally, the embodiments herein address digital TV processing requirements for a multimedia processor or digital signal processing (DSP) processor at the same time an application processor controls and runs digital TV operation, DVB-H stack control, and electronic service guides. The embodiments in accordance with the invention further address optimal performance for video playback, video recording, digital TV, still image capture, and DVR (Digital Video Recording) features on a mobile device.
In light of the foregoing description, it should also be recognized that embodiments in accordance with the present invention can be realized in numerous configurations contemplated to be within the scope and spirit of the claims. Additionally, the description above is intended by way of example only and is not intended to limit the present invention in any way, except as set forth in the following claims.
With reference now to the figures,
The MMP 100 further comprises a central processing unit (CPU) 105, a virtual file system (VFS) 110, and a plurality of ports. The plurality of ports includes at least one system bus port 120, a pass-thru storage device (PT/IO port) port 140, and a storage device (MM/IO port) port 130. In the various embodiments, the MM/IO port 130 can be coupled to a storage device or other data source. The VFS 110, the system bus port 120, and the MM/IO port 130 are all coupled to the CPU 105. The PT/IO port 140 is coupled to the MM/IO port 130 as well, via a pass-thru (PT) controller 150 managed by the CPU 105. The PT controller 150 provides the CPU 105 with the ability to signal the PT controller 150 to activate or deactivate the PT/IO port 140, thus preventing access of the data through the PT/IO port. In some embodiment, the PT/IO port 140 is normally active without any intervention from the CPU 105, thus allowing access of an associated data source to be active even if the CPU 105 is placed in a dormant state.
In the system 400 illustrated in
The AP 200 is further adapted with at least one storage device (AP/IO port) port 230. In the various embodiments, the AP/IO port 230 and the PT/IO port 140 are coupled to the same I/O bus 310, thus allowing the AP 200 access to a storage device coupled to the MM/IO port 130 via the PT/IO port 140 coupled to the PT controller 150.
In operation, the MMP 100 works in two modes. In a first mode, the MMP 100 is required to access and process multimedia data from a data source or storage device 170 coupled to the MM/IO port 130. Prior to accessing the data, the CPU 105 signals the PT controller 150 to deactivate the PT/IO port 140. The CPU 105 can then copy the data to the VFS 110, which automatically updates the AP file system through the system bus 300, if necessary. In this mode, while the MMP 100 processes the multimedia data, the AP 200 is normally inactive. In the various embodiments, the AP 200 could be further adapted to enter a low power or dormant mode, thus reducing power consumption during use of the mobile device. In the various embodiments, the AP 200 is normally utilized to control some of the functions of the mobile device. For example, in a mobile phone, the AP 200 would be used to handle incoming and outgoing calls, connecting to the network, and other functions unrelated to the output or other processing of multimedia data. In this example, it is unnecessary to maintain the AP 200 operating at full power; rather the AP 200 can be configured to operate in a low power mode in which power is only used for the synchronization of the file system 210 with the VFS 110 of the MMP 100.
In a second mode of operation of the MMP 100, a pass-thru mode, the AP 200 can access data in the data source 170 coupled to the MM/IO port 130. In the various embodiments, the AP/IO port 230 can directly access the data source 170 coupled to the MM/IO port 130 through the PT/IO port 140. In such embodiments, the AP 200 can access the data source 170, as if the AP 200 were directly coupled to the data source 170. The AP 200 can then copy the data to the AP file system 210, which automatically updates the VFS 110 through the system bus 300, if necessary. In this mode, while the AP 200 processes the data retrieved, the MMP 100 is normally inactive.
In the various embodiments, the MMP 100 could be further adapted to enter a low power or dormant mode, thus reducing power consumption during use of the mobile device. In the various embodiments, the MMP 100 is normally utilized to control processing of multimedia data. For example, in a mobile phone, the MMP 100 would be used to handle playback and recording of audio/visual data being received over a mobile network or a digital TV tuner, not to control other functions of the mobile device. In such an example, it is unnecessary to maintain the MMP 100 operating at full power; rather the MMP 100 can be configured with a low power mode in which power is only used for the synchronization of the file system 210 with the VFS 110 of the MMP 100.
In either mode of operation, because the synchronization of the VFS 110 with the file system 210 is configured to require only minimal power usage by the AP 200 and the MMP 100, this is an improvement over the prior art as shown in
The use of such modes can also improve performance when dealing with more than one storage device or data source, as shown in the system 500 of
For example, in a DVB-H digital TV mode of operation for a mobile device, a DVB-H modulator or a DVB-H demodulator/tuner chip combo 180 could be coupled to the second MM/IO port 135. For this mode, the DVB-H baseband may be monitoring several MPEG2 transport stream program IDs (PID) at any given time. For example one PID may be related with the electronic service guide, a different one with a particular TV channel. On the typical handset using the prior art, such as the system in
In the various embodiments, the invention allows the DVB-H MPEG2 transport stream Program ID (PID) with the channel data in H.264 or MPEG4 and audio data to be processed by the MMP 100 without any intervention from the AP 200. As discussed before, the AP 200 will be prevented from accessing the MM/IO port during the time the MMP 100 is accessing this particular program ID. However, the AP 200 can have access to any PID trough the pass-thru mode when not in DVB-H broadcasting TV mode. Therefore, the DVB-H MPEG2 transport stream PID with the electronic service guide data can be read by AP 200 during the pass-thru mode.
However during broadcast mode, the AP 200 processor can operate in a low power mode when the MMP 100 is processing video from the DVB-H stream (180) or other data source. In some embodiments when operating in a DVB-H or mobile broadcast mode, the MMP 100 can also monitor for IP packets needed by the AP 200. As the IP packets arrive, the MMP 100 will buffer them and wakeup the AP 200 only when needed. In other words, the AP 200 can instruct the MMP 100 as to which IP packets the AP 200 needs to be alerted to and if MMP 100 needs to buffer these IP packets. This buffer option allows the AP 200 to remain in dormant state longer, yet not miss any communications. For example, instead of having to wakeup every 2 seconds, by buffering on the MMP 100, the AP 200 may only need to wake up every 3-4 seconds increasing battery life on mobile TV operation.
In the various embodiments, since the AP 200 is in a low power mode, this allows the mobile device operate with the lowest power requirements possible during digital TV playback and/or recording. Additionally, since both the digital TV and storage facilities are available to the MMP 100 without interference by the AP 200, this enables use of digital video recording (DVR) features on the mobile device, in which a broadcast channel is recorded automatically on a mass storage device while synchronizing of the VFS 110 operates at the lowest possible power. However, the AP 200 will still have access to other programs ID when program data is not being received in a particular slot.
Referring to
In light of the foregoing description, it should be recognized that embodiments in accordance with the present invention can be realized in hardware, software, or a combination of hardware and software. A network or system according to the present invention can be realized in a centralized fashion in one computer system or processor, or in a distributed fashion where different elements are spread across several interconnected computer systems or processors (such as a microprocessor and a DSP). Any kind of computer system, or other apparatus adapted for carrying out the functions described herein, is suited. A typical combination of hardware and software could be a general purpose computer system with a computer program that, when being loaded and executed, controls the computer system such that it carries out the functions described herein.
In light of the foregoing description, it should also be recognized that embodiments in accordance with the present invention can be realized in numerous configurations contemplated to be within the scope and spirit of the claims. Additionally, the description above is intended by way of example only and is not intended to limit the present invention in any way, except as set forth in the following claims.
