摘要:
An video decoder system, such as for use with MPEG video compression, uses a previous B-frame as an additional prediction source for the current B-frame, along with the past and future reference frames as defined by the MPEG specification. In one embodiment a given macroblock within a current B-frame "N" reuses pixel values from the previous B-frame "N-1" if they are "similar enough" to the anticipated pixels which would otherwise need to be computed. For a given macroblock, motion vectors for both B-frames are compared: if they differ by less than a similarity threshold value, then the pixel values from the previous B-frame are reused without further computation. The similarity threshold may be adaptively adjusted to reduce the computational burden of video decompression, while affording a gradual degradation of picture quality, rather than wholesale skipping of entire frames.
摘要:
A video decompression system utilizes multiple independent input buffers so that input/output operations and processing take place concurrently, nearly continuously and at a rate that is substantially equal to a selected maximum access rate of the storage device. Consequently, the data rate of the video decompression system is optimized with respect to the rate of data accessing. The video decompression system adaptively sets input buffer parameters as a function, for example, of processor capabilities, bitstream characteristics, drive latency and access time, and file I/O overhead.
摘要:
In accordance with some embodiments, a protected execution environment may be defined for a graphics processing unit. This framework not only protects the workloads from malware running on the graphics processing unit but also protects those workloads from malware running on the central processing unit. In addition, the trust framework may facilitate proof of secure execution by measuring the code and data structures used to execute the workload. If a part of the trusted computing base of this framework or protected execution environment is compromised, that part can be patched remotely and the patching can be proven remotely throughout attestation in some embodiments.
摘要:
In one embodiment, a processor can enforce a blacklist and validate, according to a multi-phase lockstep integrity protocol, a device coupled to the processor. Such enforcement may prevent the device from accessing one or more resources of a system prior to the validation. The blacklist may include a list of devices that have not been validated according to the multi-phase lockstep integrity protocol. Other embodiments are described and claimed.
摘要:
In one embodiment, a processor can enforce a blacklist and validate, according to a multi-phase lockstep integrity protocol, a device coupled to the processor. Such enforcement may prevent the device from accessing one or more resources of a system prior to the validation. The blacklist may include a list of devices that have not been validated according to the multi-phase lockstep integrity protocol. Other embodiments are described and claimed.
摘要:
In one embodiment, an input/output (I/O) memory management unit (IOMMU) comprises at least one memory and control logic coupled to the memory. The memory is configured to store translation data corresponding to one or more I/O translation tables stored in a memory system of a computer system that includes the IOMMU. The control logic is configured to translate an I/O device-generated memory request using the translation data. The translation data includes a type field indicating one or more attributes of the translation, and the control logic is configured to control the translation responsive to the type field.
摘要:
In an embodiment, an input/output (I/O) memory management unit (IOMMU) comprises at least one memory configured to store translation data; and control logic coupled to the memory and configured to translate an I/O device-generated memory request using the translation data. The translation data corresponds to one or more device table entries in a device table stored in a memory system of a computer system that includes the IOMMU, wherein the device table entry for a given request is selected by an identifier corresponding to the I/O device that generates the request. The translation data further corresponds to one or more I/O page tables, wherein the selected device table entry for the given request includes a pointer to a set of I/O page tables to be used to translate the given request.
摘要:
In one embodiment, a system comprises one or more input/output (I/O) devices; an I/O memory management unit (IOMMU) coupled to receive memory requests sourced by the I/O devices and configured to provide address translation for the memory requests; and a virtual machine monitor (VMM) configured to manage one or more virtual machines on the system, wherein the VMM is configured to virtualize the IOMMU, providing one or more virtual IOMMUs for use by one or more virtual machines.
摘要翻译:在一个实施例中,系统包括一个或多个输入/输出(I / O)设备; I / O存储器管理单元(IOMMU),其耦合以接收由所述I / O设备提供的存储器请求,并被配置为提供所述存储器请求的地址转换; 以及被配置为管理所述系统上的一个或多个虚拟机的虚拟机监视器(VMM),其中所述VMM被配置为虚拟化所述IOMMU,提供一个或多个虚拟IOMMU供一个或多个虚拟机使用。
摘要:
The present invention provides a method and apparatus for securing portions of a memory. The method includes identifying information for protection and indicating at least one physical address of a memory that houses the information as at least one of read and write disabled. The method includes receiving a request from a program to access the information. The method further includes accessing the information in response to determining that the program has the authority to access the information. The apparatus includes a memory comprising a privileged code. The privileged code is capable of receiving a request to protect selected information and indicating at least one physical address of a memory housing the information as at least one of read and write disabled. The privileged code is capable of receiving a request from a program to access the information. The privileged code is further capable of accessing the information in response to determining that the program has the authority to access the information.
摘要:
A computer system includes a main processor and a security control processor that is coupled to the main processor and configured to control and monitor an operational state of the main processor. To ensure the computer system may be trusted, the security control processor may be configured to hold the main processor in a slave mode during initialization of the security control processor such that the main processor is not operable to fetch and execute instructions from an instruction source external to the main processor, for example. In addition, the security control processor may be configured to initialize the operational state of the main processor to a predetermined state by transferring to the main processor via a control interface one or more instructions and to cause the main processor to execute the one or more instructions while the main processor is held in the slave mode.