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This makes it easier to automatically generate parts of the manager documentation in the future. Update #3993.
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24 lines
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.. SPDX-License-Identifier: CC-BY-SA-4.0
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.. Copyright (C) 1988, 2008 On-Line Applications Research Corporation (OAR)
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.. index:: dual ported memory, definition
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.. index:: external addresses, definition
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.. index:: internal addresses, definition
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Background
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==========
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A dual-ported memory area (DPMA) is an contiguous block of RAM owned by a
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particular processor but which can be accessed by other processors in the
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system. The owner accesses the memory using internal addresses, while other
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processors must use external addresses. RTEMS defines a port as a particular
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mapping of internal and external addresses.
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There are two system configurations in which dual-ported memory is commonly
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found. The first is tightly-coupled multiprocessor computer systems where the
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dual-ported memory is shared between all nodes and is used for inter-node
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communication. The second configuration is computer systems with intelligent
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peripheral controllers. These controllers typically utilize the DPMA for
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high-performance data transfers.
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