Patent · US Expired

Method and apparatus to permit the boot of a shared memory buffer architecture employing an arbitrary operating system

US5790849A · kind A · utility

30Cited by
4References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 22, 1995
Grant dateAug 4, 1998
Priority date
Expiry dateDec 22, 2015

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F12/0684
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A method and system for allowing an arbitrary operating boot in a shared memory buffer architecture system. A chipset including a memory controller, a bridge, and an arbitration unit is used to control access to a shared physical memory. The physical memory is divided between the system memory and dedicated memory to be used by one or more devices. A portion of the physical memory is allocated as a dedicated memory for some system device. The remainder of the memory may be allocated as system memory. The allocation is performed by a system BIOS either at initial start up or through system BIOS calls made during initialization of the device to use the dedicated memory. Programmable bits in the chipset are programmed to prevent the memory controller from claiming dedicated memory accesses during the boot of an operating system. Since the operating system's attempts to write to the dedicated memory are not claimed by the memory controller during memory sizing, they are forwarded to an I/O bus. No 1/0 device claims these addresses, so a memory sizing read back is unanswered, and the operating system is caused to believe the top of memory has been reached below the dedicated memory. If …

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.