Search results
Results from the WOW.Com Content Network
SMM is a special-purpose operating mode provided for handling system-wide functions like power management, system hardware control, or proprietary OEM designed code. It is intended for use only by system firmware (BIOS or UEFI), not by applications software or general-purpose systems software. The main benefit of SMM is that it offers a ...
In the cycle stealing mode, the DMA controller obtains access to the system bus the same way as in burst mode, using BR (Bus Request) and BG signals, which are the two signals controlling the interface between the CPU and the DMA controller. However, in cycle stealing mode, after one unit of data transfer, the control of the system bus is ...
Higher performance hardware such as graphics cards use DMA to access memory directly; in a virtual environment all memory addresses are re-mapped by the virtual machine software, which causes DMA devices to fail. The IOMMU handles this re-mapping, allowing the native device drivers to be used in a guest operating system.
Driver Verifier is a tool included in Microsoft Windows that replaces the default operating system subroutines with ones that are specifically developed to catch device driver bugs. [1] Once enabled, it monitors and stresses drivers to detect illegal function calls or actions that may be causing system corruption.
Some operating systems, notably Windows Vista, Windows 7, Windows 8, Windows 8.1 and Windows 10, do not configure themselves to load the AHCI driver upon boot if the SATA controller was not in AHCI mode at the time the operating system was installed. Although this is an easily rectifiable condition, it remains an ongoing issue with the AHCI ...
Memory-mapped I/O is preferred in IA-32 and x86-64 based architectures because the instructions that perform port-based I/O are limited to one register: EAX, AX, and AL are the only registers that data can be moved into or out of, and either a byte-sized immediate value in the instruction or a value in register DX determines which port is the source or destination port of the transfer.
The GART allows the graphics card direct memory access (DMA) to the host system memory, through which buffers of textures, polygon meshes and other data are loaded. AMD later reused the same mechanism for I/O virtualization with other peripherals including disk controllers and network adapters .
WDM is the driver model used since the advent of Windows 98, whereas KMDF is the driver framework Microsoft advocates and uses for Windows 2000 and beyond. In general, since more features like power management and plug and play are handled by the KMDF framework, a KMDF driver is less complicated and has less code than an equivalent WDM driver.