From 891d63bdddbd0539f031dd680ef62b3e5249b6b7 Mon Sep 17 00:00:00 2001 From: Joel Sherrill Date: Thu, 14 Feb 2002 22:14:59 +0000 Subject: 2002-02-04 Joel Sherrill * bsp.t, BSP_TIMES, callconv.t, ChangeLog, cpumodel.t, cputable.t, fatalerr.t, intr_NOTIMES.t, Makefile.am, memmodel.t, mips.texi, preface.texi, stamp-vti, timeBSP.t, version.texi: New files. --- doc/supplements/mips/memmodel.t | 39 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+) create mode 100644 doc/supplements/mips/memmodel.t (limited to 'doc/supplements/mips/memmodel.t') diff --git a/doc/supplements/mips/memmodel.t b/doc/supplements/mips/memmodel.t new file mode 100644 index 0000000000..ef35072230 --- /dev/null +++ b/doc/supplements/mips/memmodel.t @@ -0,0 +1,39 @@ +@c +@c COPYRIGHT (c) 1988-2002. +@c On-Line Applications Research Corporation (OAR). +@c All rights reserved. +@c +@c $Id$ +@c + +@chapter Memory Model + +@section Introduction + +A processor may support any combination of memory +models ranging from pure physical addressing to complex demand +paged virtual memory systems. RTEMS supports a flat memory +model which ranges contiguously over the processor's allowable +address space. RTEMS does not support segmentation or virtual +memory of any kind. The appropriate memory model for RTEMS +provided by the targeted processor and related characteristics +of that model are described in this chapter. + +@section Flat Memory Model + +The XXX family supports a flat 32-bit address +space with addresses ranging from 0x00000000 to 0xFFFFFFFF (4 +gigabytes). Each address is represented by a 32-bit value and +is byte addressable. The address may be used to reference a +single byte, word (2-bytes), or long word (4 bytes). Memory +accesses within this address space are performed in big endian +fashion by the processors in this family. + +Some of the XXX family members such as the +XXX, XXX, and XXX support virtual memory and +segmentation. The XXX requires external hardware support +such as the XXX Paged Memory Management Unit coprocessor +which is typically used to perform address translations for +these systems. RTEMS does not support virtual memory or +segmentation on any of the XXX family members. + -- cgit v1.2.3