摘要:
A hardware platform includes a nonvolatile storage device that can store system firmware as well as code for the primary operating system for the hardware platform. The hardware platform includes a controller that determines the hardware platform lacks functional firmware to boot the primary operating system from the storage device. The controller accesses a firmware image from an external interface that interfaces a device external to the hardware platform, where the external device is a firmware image source. The controller provisions the firmware from the external device to the storage device and initiates a boot sequence from the provisioned firmware.
摘要:
Disclosed in some examples are devices, methods, and machine-readable mediums for reliable control of IR LEDs. In some examples, a microcontroller running firmware controls whether the LED is activated or not by use of a disable signal. The microcontroller enables or disables the operation of the LED based upon a user's proximity to the LED, a watchdog timer, and a confirmation that only trusted software is executing.
摘要:
Systems and techniques for privacy protected input-output port control are described herein. In an example, an indication may be obtained that a protected port is disabled. A set of application attributes stored in a secure memory location may be compared to a set of attested application attributes to create a verification flag. At least one port attribute of the protected port may be obtained based on the verification flag. The protected port may be enabled using the at least one port attribute. Other examples, for controlling an input-output port using computer firmware and trusted execution techniques are further disclosed.
摘要:
A package with a processing device and integrated cryptographic firmware is described. The package includes a processing device including a processing module to execute a system management mode and a non-volatile memory storing cryptographic firmware to execute one or more cryptographic functions in the system management mode.
摘要:
A platform may use a central processing unit to run an operating system. Independently of the operating system, in the central processing unit, a hardware controller, such as a manageability engine, may be used to control which window is on the top of the Z-order and thereby control which window is displayed to the user. As a result, in some embodiments, the hardware controller can prevent an interloper or malware from interjecting an illegitimate window over a legitimate window that the user actually desired to access. In addition, a hardware indicator may be provided to assure the user when an accessed website is legitimate.
摘要:
An apparatus including a protocol watcher adapted for use with a bus, a state machine adapted to detect known bug signatures on the bus, and a perturber adapted to intervene on the bus to prevent occurrence of bugs having those signatures. A system utilizing such includes a bus, a first agent coupled to the bus, a second agent coupled to the bus for communicating to the first agent according to a bus protocol, and the bus patcher coupled to the bus for monitoring a communication from the second agent to the first agent to identify an event which would cause an error in the apparatus, and for modifying the communication such that the event is avoided. Any of the protocol watcher, state machine, and/or perturber may be programmable.
摘要:
A method and apparatus of performing bus transactions on the bus of the computer system. The present invention includes a method and apparatus for permitting out-of-order replies in a pipelined bus system. The out-of-order responses include the sending of tokens between both the requesting agents and the responding agents in the computer system without the use of dedicated token buses.
摘要:
In a computer system having a plurality of processors, an apparatus and method for maintaining processor ordering associated with read and write operations of these processors. When data from a producer processor is initially retired, it is stored in a FIFO buffer internal to that processor. If that processor subsequently wishes access to that data, the data is retrieved from and stored back to the FIFO. The data temporarily stored in the FIFO is used to update a main memory shared by the plurality of processors. This update function occurs only after the data has been globally observed in order to guarantee that if any other processor in the system reads data from the main memory, it will obtain an updated version of that data. This ensures that the processor ordering is maintained with respect to the multiple processors residing within the computer system.
摘要:
A protocol and related apparatus for snoop stretching in a computer system having at least one requesting agent for issuing bus transaction requests and at least one snooping agent for monitoring transaction requests and issuing bus signals onto an external bus. The bus transactions are timed by a bus clock signal having a plurality of cycles. To indicate snoop stretching, during a first cycle a first snooping agent asserts both a HIT# bus signal and a HITM# bus signal together to indicate that the first snooping agent must delay assertion of valid snoop results for a predetermined snoop period. During a later cycle, to indicate the end of the snoop stretch, the first snooping agent deasserts the assertion of both the HIT# and HITM# signals together and asserts its valid snoop results. The HIT# and HITM# signals alone each represent valid snoop results. If the first snooping agent must continue delaying assertion of valid snoop results, then it reasserts both the HIT# and HITM# bus signals together for the predetermined snoop period. If a second snooping agent is ready to assert its valid snoop results, it will do so while the first snooping agent causes a snoop stretch, and will reassert its valid snoop results up to and including the cycle that the first snooping agent deasserts it snoop stretch and asserts its own valid snoop results.
摘要:
Requests to memory issued by an agent on a bus are satisfied while maintaining cache consistency. The requesting agent may issue a request to another agent, or the memory unit, by placing the request on the bus. Each agent on the bus snoops the bus to determine whether the issued request can be satisfied by accessing its cache. An agent which can satisfy the request using its cache, i.e., the snooping agent, issues a signal to the requesting agent indicating so. The snooping agent places the cache line which corresponds to the request onto the bus, which is retrieved by the requesting agent. In the event of a read request, the memory unit also retrieves the cache line data from the bus and stores the cache line in main memory. In the event of a write request, the requesting agent transfers write data over the bus along with the request. This write data is retrieved by both the memory unit, which temporarily stores the data, and the snooping agent. Subsequently, the snooping agent transfers the entire cache line over the bus. The memory unit retrieves this cache line, merges it with the write data previously stored, and writes the merged cache line to memory.