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AssigneeMotorola, Inc.
InventorsWilliam M. Keshlear, Robert B. Cohen
Estimating the term…
In a data processing system, a paged memory management unit (PMMU) translates logical addresses provided by a processor to physical addresses in a memory using translators constructed from page descriptors comprising, in part, translation tables stored in the memory. The PMMU maintains a set of recently used translators in a translator cache. In response to a particular lock value contained in a lock field of the page descriptor for a particular page, the PMMU sets a lock indicator in the translator cache associated with the corresponding translator, to preclude replacement of this translator in the translator cache. A lock warning mechanism provides a lock warning signal whenever all but a predetermined number of the translators in the cache are locked. In response, the PMMU can warn the processor that the translator cache is in danger of becoming full of locked translators. Preferably, the PMMU is also inhibited from locking the last translator in the cache.
In a paged memory management unit (PMMU) which translates each of a plurality of logical addresses into a corresponding physical address using a selected one of a plurality of page descriptors comprising one or more translation tables stored in a memory, the PMMU assembling each of said logical addresses and the corresponding physical address into a respective translator, said PMMU including:
In a paged memory management unit (PMMU) which translates each of a plurality of logical addresses into a corresponding physical address using a selected one of a plurality of page descriptors comprising one or more translation tables stored in a memory, wherein the PMMU assembles each of said logical addresses and the corresponding physical address into a respective translator and selectively locks said translator in a translator cache in response to a lock signal associated with said translator, the improvement in that the lock signal comprises a lock field of the page descriptor used to assemble said translator.
Dependencies are inferred from the claim text.