Some of the recent Intel microprocessors have the capability of correcting specific hardware bugs by loading a sequence of bits called a “microcode update” into the CPU. This feature is available on all processors in the Intel P6 family, including Pentium Pro, Celeron, Pentium II, Pentium III, Pentium II Xeon, Pentium III Xeon, and the newly released Pentium 4. This feature is applicable to both single-processor and multi-processor (SMP) systems.
Some of the recent Intel microprocessors have the capability of correcting specific hardware bugs by loading a sequence of bits called a “microcode update” into the CPU. This feature is available on all processors in the Intel P6 family, including Pentium Pro, Celeron, Pentium II, Pentium III, Pentium II Xeon, Pentium III Xeon, and the newly released Pentium 4. This feature is applicable to both single-processor and multi-processor (SMP) systems.
The loading of a microcode update is usually delegated to the BIOS but can also be performed by the operating system without needing to run in a special mode or reboot after the update is done. It is also possible (and quite common) to have the BIOS apply a microcode update to some revision level and later have the OS upgrade it to a newer revision.
The support for microcode update for the P6 family processors was added to the Linux kernel in February 2000 as of version 2.3.46. Support for the Pentium 4 microcode updates was added to Linux 2.4.0-test12 in December of the same year. The driver (P6 family only) has been backported to Linux 2.2 but has lagged behind the “officially-supported” 2.3/2.4 version for quite a while. A set of fixes (including Pentium 4 support) has been sent by the author to Alan Cox and are likely to go into the official 2.2 series at the time of 2.2.19, which was not released at the time of this writing. The other Unix-like IA32 operating…
Please log in to view this content.
Not Yet a Member?
Register with LinuxMagazine.com and get free access to the entire archive, including:
